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#1
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Dynaco A25 XL Speaker - Need crossover diagram.
As a followup to my earlier positing about weak bass from my recently
purchased Dynaco A25XL speakers (not A25's - but A25XL !!), I am searching for an article/review on these A25XL's that would include a diagram or description of the crossover. I just want to assure myself that somewhere back in time that a previous owner did't muck around with the cross-overs and perhaps cause the weak bass that I now encounter. (Remember that I even replaced the original woofers with SEAS' current replacement for the Dynaco driver but with NO improvement!!) Thanks for any help! Pete ) |
#2
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Dynaco A25 XL Speaker - Need crossover diagram.
How are they positioned with respect to the floor, side walls, and back
wall? "Pete Snyder" wrote in message om... As a followup to my earlier positing about weak bass from my recently purchased Dynaco A25XL speakers (not A25's - but A25XL !!), I am searching for an article/review on these A25XL's that would include a diagram or description of the crossover. I just want to assure myself that somewhere back in time that a previous owner did't muck around with the cross-overs and perhaps cause the weak bass that I now encounter. (Remember that I even replaced the original woofers with SEAS' current replacement for the Dynaco driver but with NO improvement!!) Thanks for any help! Pete ) |
#3
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Dynaco A25 XL Speaker - Need crossover diagram.
How are they positioned with respect to the floor, side walls, and back
wall? "Pete Snyder" wrote in message om... As a followup to my earlier positing about weak bass from my recently purchased Dynaco A25XL speakers (not A25's - but A25XL !!), I am searching for an article/review on these A25XL's that would include a diagram or description of the crossover. I just want to assure myself that somewhere back in time that a previous owner did't muck around with the cross-overs and perhaps cause the weak bass that I now encounter. (Remember that I even replaced the original woofers with SEAS' current replacement for the Dynaco driver but with NO improvement!!) Thanks for any help! Pete ) |
#4
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Dynaco A25 XL Speaker - Need crossover diagram.
How are they positioned with respect to the floor, side walls, and back
wall? "Pete Snyder" wrote in message om... As a followup to my earlier positing about weak bass from my recently purchased Dynaco A25XL speakers (not A25's - but A25XL !!), I am searching for an article/review on these A25XL's that would include a diagram or description of the crossover. I just want to assure myself that somewhere back in time that a previous owner did't muck around with the cross-overs and perhaps cause the weak bass that I now encounter. (Remember that I even replaced the original woofers with SEAS' current replacement for the Dynaco driver but with NO improvement!!) Thanks for any help! Pete ) |
#5
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Dynaco A25 XL Speaker - Need crossover diagram.
How are they positioned with respect to the floor, side walls, and back
wall? "Pete Snyder" wrote in message om... As a followup to my earlier positing about weak bass from my recently purchased Dynaco A25XL speakers (not A25's - but A25XL !!), I am searching for an article/review on these A25XL's that would include a diagram or description of the crossover. I just want to assure myself that somewhere back in time that a previous owner did't muck around with the cross-overs and perhaps cause the weak bass that I now encounter. (Remember that I even replaced the original woofers with SEAS' current replacement for the Dynaco driver but with NO improvement!!) Thanks for any help! Pete ) |
#6
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Dynaco A25 XL Speaker - Need crossover diagram.
"Pete Snyder" wrote in message
om As a followup to my earlier positing about weak bass from my recently purchased Dynaco A25XL speakers (not A25's - but A25XL !!), I am searching for an article/review on these A25XL's that would include a diagram or description of the crossover. I just want to assure myself that somewhere back in time that a previous owner did't muck around with the cross-overs and perhaps cause the weak bass that I now encounter. (Remember that I even replaced the original woofers with SEAS' current replacement for the Dynaco driver but with NO improvement!!) Thanks for any help! All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer. |
#7
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Dynaco A25 XL Speaker - Need crossover diagram.
"Pete Snyder" wrote in message
om As a followup to my earlier positing about weak bass from my recently purchased Dynaco A25XL speakers (not A25's - but A25XL !!), I am searching for an article/review on these A25XL's that would include a diagram or description of the crossover. I just want to assure myself that somewhere back in time that a previous owner did't muck around with the cross-overs and perhaps cause the weak bass that I now encounter. (Remember that I even replaced the original woofers with SEAS' current replacement for the Dynaco driver but with NO improvement!!) Thanks for any help! All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer. |
#8
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Dynaco A25 XL Speaker - Need crossover diagram.
"Pete Snyder" wrote in message
om As a followup to my earlier positing about weak bass from my recently purchased Dynaco A25XL speakers (not A25's - but A25XL !!), I am searching for an article/review on these A25XL's that would include a diagram or description of the crossover. I just want to assure myself that somewhere back in time that a previous owner did't muck around with the cross-overs and perhaps cause the weak bass that I now encounter. (Remember that I even replaced the original woofers with SEAS' current replacement for the Dynaco driver but with NO improvement!!) Thanks for any help! All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer. |
#9
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Dynaco A25 XL Speaker - Need crossover diagram.
"Pete Snyder" wrote in message
om As a followup to my earlier positing about weak bass from my recently purchased Dynaco A25XL speakers (not A25's - but A25XL !!), I am searching for an article/review on these A25XL's that would include a diagram or description of the crossover. I just want to assure myself that somewhere back in time that a previous owner did't muck around with the cross-overs and perhaps cause the weak bass that I now encounter. (Remember that I even replaced the original woofers with SEAS' current replacement for the Dynaco driver but with NO improvement!!) Thanks for any help! All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer. |
#10
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Dynaco A25 XL Speaker - Need crossover diagram.
"Arny Krueger" wrote in message ...
"Pete Snyder" wrote in message om As a followup to my earlier positing about weak bass from my recently purchased Dynaco A25XL speakers (not A25's - but A25XL !!), I am searching for an article/review on these A25XL's that would include a diagram or description of the crossover. I just want to assure myself that somewhere back in time that a previous owner did't muck around with the cross-overs and perhaps cause the weak bass that I now encounter. (Remember that I even replaced the original woofers with SEAS' current replacement for the Dynaco driver but with NO improvement!!) Thanks for any help! All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer. Not so. IN a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter Two very different topologies This is not to say the A-25 is one or the other, but beware a generalization like: "All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer." There is nothing that intrinsically requires a simple crossover to be designed in this fashion. |
#11
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Dynaco A25 XL Speaker - Need crossover diagram.
"Arny Krueger" wrote in message ...
"Pete Snyder" wrote in message om As a followup to my earlier positing about weak bass from my recently purchased Dynaco A25XL speakers (not A25's - but A25XL !!), I am searching for an article/review on these A25XL's that would include a diagram or description of the crossover. I just want to assure myself that somewhere back in time that a previous owner did't muck around with the cross-overs and perhaps cause the weak bass that I now encounter. (Remember that I even replaced the original woofers with SEAS' current replacement for the Dynaco driver but with NO improvement!!) Thanks for any help! All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer. Not so. IN a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter Two very different topologies This is not to say the A-25 is one or the other, but beware a generalization like: "All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer." There is nothing that intrinsically requires a simple crossover to be designed in this fashion. |
#12
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Dynaco A25 XL Speaker - Need crossover diagram.
"Arny Krueger" wrote in message ...
"Pete Snyder" wrote in message om As a followup to my earlier positing about weak bass from my recently purchased Dynaco A25XL speakers (not A25's - but A25XL !!), I am searching for an article/review on these A25XL's that would include a diagram or description of the crossover. I just want to assure myself that somewhere back in time that a previous owner did't muck around with the cross-overs and perhaps cause the weak bass that I now encounter. (Remember that I even replaced the original woofers with SEAS' current replacement for the Dynaco driver but with NO improvement!!) Thanks for any help! All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer. Not so. IN a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter Two very different topologies This is not to say the A-25 is one or the other, but beware a generalization like: "All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer." There is nothing that intrinsically requires a simple crossover to be designed in this fashion. |
#13
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Dynaco A25 XL Speaker - Need crossover diagram.
"Arny Krueger" wrote in message ...
"Pete Snyder" wrote in message om As a followup to my earlier positing about weak bass from my recently purchased Dynaco A25XL speakers (not A25's - but A25XL !!), I am searching for an article/review on these A25XL's that would include a diagram or description of the crossover. I just want to assure myself that somewhere back in time that a previous owner did't muck around with the cross-overs and perhaps cause the weak bass that I now encounter. (Remember that I even replaced the original woofers with SEAS' current replacement for the Dynaco driver but with NO improvement!!) Thanks for any help! All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer. Not so. IN a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter Two very different topologies This is not to say the A-25 is one or the other, but beware a generalization like: "All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer." There is nothing that intrinsically requires a simple crossover to be designed in this fashion. |
#14
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Dynaco A25 XL Speaker - Need crossover diagram.
Dick Pierce wrote:
"Arny Krueger" wrote in message ... "Pete Snyder" wrote in message .com As a followup to my earlier positing about weak bass from my recently purchased Dynaco A25XL speakers (not A25's - but A25XL !!), I am searching for an article/review on these A25XL's that would include a diagram or description of the crossover. I just want to assure myself that somewhere back in time that a previous owner did't muck around with the cross-overs and perhaps cause the weak bass that I now encounter. (Remember that I even replaced the original woofers with SEAS' current replacement for the Dynaco driver but with NO improvement!!) Thanks for any help! All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer. Not so. IN a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter Two very different topologies This is not to say the A-25 is one or the other, but beware a generalization like: "All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer." There is nothing that intrinsically requires a simple crossover to be designed in this fashion. I have never looked at the A25XL crossover but I did measure a complete system 2 yrs ago;the woofer has a 2nd order rolloff at 1.5khz as seen in a nearfield measurement so there must be at least an inductor to give the 1st 6db/octave;the 2nd 6db could come from the natural rolloff of the 10" WFR. An OHMETER reading at the box input terminals gave 4.7 ohm. A complete Quasi-Anechoic measurement had -3/-10db points at 63/44hz with respect to the midband. |
#15
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Dynaco A25 XL Speaker - Need crossover diagram.
Dick Pierce wrote:
"Arny Krueger" wrote in message ... "Pete Snyder" wrote in message .com As a followup to my earlier positing about weak bass from my recently purchased Dynaco A25XL speakers (not A25's - but A25XL !!), I am searching for an article/review on these A25XL's that would include a diagram or description of the crossover. I just want to assure myself that somewhere back in time that a previous owner did't muck around with the cross-overs and perhaps cause the weak bass that I now encounter. (Remember that I even replaced the original woofers with SEAS' current replacement for the Dynaco driver but with NO improvement!!) Thanks for any help! All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer. Not so. IN a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter Two very different topologies This is not to say the A-25 is one or the other, but beware a generalization like: "All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer." There is nothing that intrinsically requires a simple crossover to be designed in this fashion. I have never looked at the A25XL crossover but I did measure a complete system 2 yrs ago;the woofer has a 2nd order rolloff at 1.5khz as seen in a nearfield measurement so there must be at least an inductor to give the 1st 6db/octave;the 2nd 6db could come from the natural rolloff of the 10" WFR. An OHMETER reading at the box input terminals gave 4.7 ohm. A complete Quasi-Anechoic measurement had -3/-10db points at 63/44hz with respect to the midband. |
#16
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Dynaco A25 XL Speaker - Need crossover diagram.
Dick Pierce wrote:
"Arny Krueger" wrote in message ... "Pete Snyder" wrote in message .com As a followup to my earlier positing about weak bass from my recently purchased Dynaco A25XL speakers (not A25's - but A25XL !!), I am searching for an article/review on these A25XL's that would include a diagram or description of the crossover. I just want to assure myself that somewhere back in time that a previous owner did't muck around with the cross-overs and perhaps cause the weak bass that I now encounter. (Remember that I even replaced the original woofers with SEAS' current replacement for the Dynaco driver but with NO improvement!!) Thanks for any help! All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer. Not so. IN a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter Two very different topologies This is not to say the A-25 is one or the other, but beware a generalization like: "All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer." There is nothing that intrinsically requires a simple crossover to be designed in this fashion. I have never looked at the A25XL crossover but I did measure a complete system 2 yrs ago;the woofer has a 2nd order rolloff at 1.5khz as seen in a nearfield measurement so there must be at least an inductor to give the 1st 6db/octave;the 2nd 6db could come from the natural rolloff of the 10" WFR. An OHMETER reading at the box input terminals gave 4.7 ohm. A complete Quasi-Anechoic measurement had -3/-10db points at 63/44hz with respect to the midband. |
#17
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Dynaco A25 XL Speaker - Need crossover diagram.
Dick Pierce wrote:
"Arny Krueger" wrote in message ... "Pete Snyder" wrote in message .com As a followup to my earlier positing about weak bass from my recently purchased Dynaco A25XL speakers (not A25's - but A25XL !!), I am searching for an article/review on these A25XL's that would include a diagram or description of the crossover. I just want to assure myself that somewhere back in time that a previous owner did't muck around with the cross-overs and perhaps cause the weak bass that I now encounter. (Remember that I even replaced the original woofers with SEAS' current replacement for the Dynaco driver but with NO improvement!!) Thanks for any help! All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer. Not so. IN a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter Two very different topologies This is not to say the A-25 is one or the other, but beware a generalization like: "All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer." There is nothing that intrinsically requires a simple crossover to be designed in this fashion. I have never looked at the A25XL crossover but I did measure a complete system 2 yrs ago;the woofer has a 2nd order rolloff at 1.5khz as seen in a nearfield measurement so there must be at least an inductor to give the 1st 6db/octave;the 2nd 6db could come from the natural rolloff of the 10" WFR. An OHMETER reading at the box input terminals gave 4.7 ohm. A complete Quasi-Anechoic measurement had -3/-10db points at 63/44hz with respect to the midband. |
#18
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Dynaco A25 XL Speaker - Need crossover diagram.
An inductor in parallel with a tweeter, without a series capacitor, would be
seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Not so. IN a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter Two very different topologies This is not to say the A-25 is one or the other, but beware a generalization like: "All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer." There is nothing that intrinsically requires a simple crossover to be designed in this fashion. |
#19
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Dynaco A25 XL Speaker - Need crossover diagram.
An inductor in parallel with a tweeter, without a series capacitor, would be
seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Not so. IN a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter Two very different topologies This is not to say the A-25 is one or the other, but beware a generalization like: "All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer." There is nothing that intrinsically requires a simple crossover to be designed in this fashion. |
#20
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Dynaco A25 XL Speaker - Need crossover diagram.
An inductor in parallel with a tweeter, without a series capacitor, would be
seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Not so. IN a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter Two very different topologies This is not to say the A-25 is one or the other, but beware a generalization like: "All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer." There is nothing that intrinsically requires a simple crossover to be designed in this fashion. |
#21
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Dynaco A25 XL Speaker - Need crossover diagram.
An inductor in parallel with a tweeter, without a series capacitor, would be
seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Not so. IN a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter Two very different topologies This is not to say the A-25 is one or the other, but beware a generalization like: "All you need to know is that in a simple 2-way crossover, the capacitor if any goes in series with the tweeter, and the inductor if any goes in series with the woofer." There is nothing that intrinsically requires a simple crossover to be designed in this fashion. |
#22
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Dynaco A25 XL Speaker - Need crossover diagram.
"Tim Padrick" wrote in message
An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Agreed, and that leaves some non-simple problems to solve. AFAIK the very few commercial designs with an inductor in parallel with the tweeter use a tweeter that is more efficient than the woofer, and put a resistor in series with the inductor/tweeter combination. Still not a pretty picture. |
#23
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Dynaco A25 XL Speaker - Need crossover diagram.
"Tim Padrick" wrote in message
An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Agreed, and that leaves some non-simple problems to solve. AFAIK the very few commercial designs with an inductor in parallel with the tweeter use a tweeter that is more efficient than the woofer, and put a resistor in series with the inductor/tweeter combination. Still not a pretty picture. |
#24
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Dynaco A25 XL Speaker - Need crossover diagram.
"Tim Padrick" wrote in message
An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Agreed, and that leaves some non-simple problems to solve. AFAIK the very few commercial designs with an inductor in parallel with the tweeter use a tweeter that is more efficient than the woofer, and put a resistor in series with the inductor/tweeter combination. Still not a pretty picture. |
#25
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Dynaco A25 XL Speaker - Need crossover diagram.
"Tim Padrick" wrote in message
An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Agreed, and that leaves some non-simple problems to solve. AFAIK the very few commercial designs with an inductor in parallel with the tweeter use a tweeter that is more efficient than the woofer, and put a resistor in series with the inductor/tweeter combination. Still not a pretty picture. |
#26
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Dynaco A25 XL Speaker - Need crossover diagram.
"Tim Padrick" wrote in message ...
Not so. In a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Too bad you didn't try to understand or analyze the circuit. If you were to put JUST a tweeter and JUST an inductor in parallel across an amp, you'd be right, but that's VERY clearly, from the topology above, NOT what is happening. You cannot look at a circuit and simpy pick little pieces of it and expect a quick analysis based on one piece to give you a coherent picture of the whole. Let's, in fact, do a more complete analysis and see what is REALLY happening We'll make some simplifying assumption just to make the analysis easier: we'll replace XWoofer and XTweeter with resistive loads RWoofer and RTweeter. Start at frequencies well below the crossover point. At these frequencies the impedance of shunt capacitor CWoof is very high, and that of the shunt inductor LTweet is very low. As a result, the current flows through the woofer leg (RWoofer) and through the inductor LTweet) And the amplifier sees, essentially, the woofer as the load. Now, at high frequencies well ABOVE the crossover point, the impedance of the shunt capacitor CWoof is very low and that of the shunt inductor LTweet is very high. As a result, the current flows through the shunt capacitor (CWoofer), bypassing the woofer and flowing through the tweeter leg. And the amplifier sees, essentially, the tweeter as the load. Around the crossover, the impedance of the two shunt reactances LTweet and CWoof) are about the same, and are also about the same as the impedances of the woofer and tweeter (assuming we don't pick values out of thin air, like I did). In such a condition, equal amounts of the current flow through each leg of the mesh, meaning the power to the woofer and tweeter are about the same. And the load seen by the amplifier is the parallel combination of the woofer mesh and tweeter mesh. Contrary to your analysis at NO point does the amplifier EVER see a short circuit. Let's in fact do a more precise analysis. I have adjusted the values to something a bit more practical, aiming for a 1 kHz crossover. Here's the new circuit: * Series crossover analysis Vin 1 0 AC SIN 1.0 0.0 CWoof 1 2 25UF RWoof 1 2 8 LTweet 2 0 1MH RTweet 2 0 8 .AC OCT 3 20 20K .PRINT AC VDB(1, 2) VDB(2,0) .END Now, here's the output response across the woofer terminals and the tweeter terminals, plotted every 1/3 octave: Frequency Woofer Tweeter Response Response ---------- -------- -------- 20 Hz 0.0 dB -36.1 dB 25.2 0.0 -34.1 31.7 0.0 -32.1 40 0.0 -30.1 50.4 0.0 -28 63.5 0.0 -26 80 0.0 -24 101 0.0 -22 127 0.0 -19.9 160 0.0 -17.9 202 0.0 -15.8 254 0.0 -13.7 320 0.0 -11.6 403 0.0 -9.4 508 -0.1 -7.3 640 -0.4 -5.2 806 -0.9 -3.3 1020 -1.9 -1.8 1280 -3.4 -0.9 1610 -5.3 -0.3 2030 -7.4 -0.1 2560 -9.6 -0.0 3230 -11.8 0.0 4060 -13.9 0.0 5120 -16 0.0 6450 -18.1 0.0 8130 -20.1 0.0 10200 -22.1 0.0 12900 -24.2 0.0 16300 -26.2 0.0 20500 -28.2 0.0 As you can see, the response problems you predict simply do not happen. Now, as to the assertion of there being a "short circuit" across the amplifier, let's look at the impedance: Frequency Impedance ---------- --------- 20 Hz 8 Ohms 25.2 8 31.7 7.99 40 7.99 50.4 7.98 63.5 7.97 80 7.96 101 7.93 127 7.89 160 7.83 202 7.74 254 7.61 320 7.41 403 7.16 508 6.84 640 6.51 806 6.25 1020 6.15 1280 6.26 1610 6.53 2030 6.87 2560 7.18 3230 7.43 4060 7.62 5120 7.75 6450 7.84 8130 7.9 10200 7.93 12900 7.96 16300 7.97 20500 7.98 At no point does the impedance EVER drop below 6 ohms. Hardly a short as you claim. Let's even look at DC, where the inductor impedance is 0 and the capacitor impedance is infinite: the imepdance of the total cricuit is that of the woofer. At infinite frequency, where the impedance of the capacitor is 0 and the inductor is infinite, the impedance is that of the tweeter. |
#27
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Dynaco A25 XL Speaker - Need crossover diagram.
"Tim Padrick" wrote in message ...
Not so. In a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Too bad you didn't try to understand or analyze the circuit. If you were to put JUST a tweeter and JUST an inductor in parallel across an amp, you'd be right, but that's VERY clearly, from the topology above, NOT what is happening. You cannot look at a circuit and simpy pick little pieces of it and expect a quick analysis based on one piece to give you a coherent picture of the whole. Let's, in fact, do a more complete analysis and see what is REALLY happening We'll make some simplifying assumption just to make the analysis easier: we'll replace XWoofer and XTweeter with resistive loads RWoofer and RTweeter. Start at frequencies well below the crossover point. At these frequencies the impedance of shunt capacitor CWoof is very high, and that of the shunt inductor LTweet is very low. As a result, the current flows through the woofer leg (RWoofer) and through the inductor LTweet) And the amplifier sees, essentially, the woofer as the load. Now, at high frequencies well ABOVE the crossover point, the impedance of the shunt capacitor CWoof is very low and that of the shunt inductor LTweet is very high. As a result, the current flows through the shunt capacitor (CWoofer), bypassing the woofer and flowing through the tweeter leg. And the amplifier sees, essentially, the tweeter as the load. Around the crossover, the impedance of the two shunt reactances LTweet and CWoof) are about the same, and are also about the same as the impedances of the woofer and tweeter (assuming we don't pick values out of thin air, like I did). In such a condition, equal amounts of the current flow through each leg of the mesh, meaning the power to the woofer and tweeter are about the same. And the load seen by the amplifier is the parallel combination of the woofer mesh and tweeter mesh. Contrary to your analysis at NO point does the amplifier EVER see a short circuit. Let's in fact do a more precise analysis. I have adjusted the values to something a bit more practical, aiming for a 1 kHz crossover. Here's the new circuit: * Series crossover analysis Vin 1 0 AC SIN 1.0 0.0 CWoof 1 2 25UF RWoof 1 2 8 LTweet 2 0 1MH RTweet 2 0 8 .AC OCT 3 20 20K .PRINT AC VDB(1, 2) VDB(2,0) .END Now, here's the output response across the woofer terminals and the tweeter terminals, plotted every 1/3 octave: Frequency Woofer Tweeter Response Response ---------- -------- -------- 20 Hz 0.0 dB -36.1 dB 25.2 0.0 -34.1 31.7 0.0 -32.1 40 0.0 -30.1 50.4 0.0 -28 63.5 0.0 -26 80 0.0 -24 101 0.0 -22 127 0.0 -19.9 160 0.0 -17.9 202 0.0 -15.8 254 0.0 -13.7 320 0.0 -11.6 403 0.0 -9.4 508 -0.1 -7.3 640 -0.4 -5.2 806 -0.9 -3.3 1020 -1.9 -1.8 1280 -3.4 -0.9 1610 -5.3 -0.3 2030 -7.4 -0.1 2560 -9.6 -0.0 3230 -11.8 0.0 4060 -13.9 0.0 5120 -16 0.0 6450 -18.1 0.0 8130 -20.1 0.0 10200 -22.1 0.0 12900 -24.2 0.0 16300 -26.2 0.0 20500 -28.2 0.0 As you can see, the response problems you predict simply do not happen. Now, as to the assertion of there being a "short circuit" across the amplifier, let's look at the impedance: Frequency Impedance ---------- --------- 20 Hz 8 Ohms 25.2 8 31.7 7.99 40 7.99 50.4 7.98 63.5 7.97 80 7.96 101 7.93 127 7.89 160 7.83 202 7.74 254 7.61 320 7.41 403 7.16 508 6.84 640 6.51 806 6.25 1020 6.15 1280 6.26 1610 6.53 2030 6.87 2560 7.18 3230 7.43 4060 7.62 5120 7.75 6450 7.84 8130 7.9 10200 7.93 12900 7.96 16300 7.97 20500 7.98 At no point does the impedance EVER drop below 6 ohms. Hardly a short as you claim. Let's even look at DC, where the inductor impedance is 0 and the capacitor impedance is infinite: the imepdance of the total cricuit is that of the woofer. At infinite frequency, where the impedance of the capacitor is 0 and the inductor is infinite, the impedance is that of the tweeter. |
#28
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Dynaco A25 XL Speaker - Need crossover diagram.
"Tim Padrick" wrote in message ...
Not so. In a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Too bad you didn't try to understand or analyze the circuit. If you were to put JUST a tweeter and JUST an inductor in parallel across an amp, you'd be right, but that's VERY clearly, from the topology above, NOT what is happening. You cannot look at a circuit and simpy pick little pieces of it and expect a quick analysis based on one piece to give you a coherent picture of the whole. Let's, in fact, do a more complete analysis and see what is REALLY happening We'll make some simplifying assumption just to make the analysis easier: we'll replace XWoofer and XTweeter with resistive loads RWoofer and RTweeter. Start at frequencies well below the crossover point. At these frequencies the impedance of shunt capacitor CWoof is very high, and that of the shunt inductor LTweet is very low. As a result, the current flows through the woofer leg (RWoofer) and through the inductor LTweet) And the amplifier sees, essentially, the woofer as the load. Now, at high frequencies well ABOVE the crossover point, the impedance of the shunt capacitor CWoof is very low and that of the shunt inductor LTweet is very high. As a result, the current flows through the shunt capacitor (CWoofer), bypassing the woofer and flowing through the tweeter leg. And the amplifier sees, essentially, the tweeter as the load. Around the crossover, the impedance of the two shunt reactances LTweet and CWoof) are about the same, and are also about the same as the impedances of the woofer and tweeter (assuming we don't pick values out of thin air, like I did). In such a condition, equal amounts of the current flow through each leg of the mesh, meaning the power to the woofer and tweeter are about the same. And the load seen by the amplifier is the parallel combination of the woofer mesh and tweeter mesh. Contrary to your analysis at NO point does the amplifier EVER see a short circuit. Let's in fact do a more precise analysis. I have adjusted the values to something a bit more practical, aiming for a 1 kHz crossover. Here's the new circuit: * Series crossover analysis Vin 1 0 AC SIN 1.0 0.0 CWoof 1 2 25UF RWoof 1 2 8 LTweet 2 0 1MH RTweet 2 0 8 .AC OCT 3 20 20K .PRINT AC VDB(1, 2) VDB(2,0) .END Now, here's the output response across the woofer terminals and the tweeter terminals, plotted every 1/3 octave: Frequency Woofer Tweeter Response Response ---------- -------- -------- 20 Hz 0.0 dB -36.1 dB 25.2 0.0 -34.1 31.7 0.0 -32.1 40 0.0 -30.1 50.4 0.0 -28 63.5 0.0 -26 80 0.0 -24 101 0.0 -22 127 0.0 -19.9 160 0.0 -17.9 202 0.0 -15.8 254 0.0 -13.7 320 0.0 -11.6 403 0.0 -9.4 508 -0.1 -7.3 640 -0.4 -5.2 806 -0.9 -3.3 1020 -1.9 -1.8 1280 -3.4 -0.9 1610 -5.3 -0.3 2030 -7.4 -0.1 2560 -9.6 -0.0 3230 -11.8 0.0 4060 -13.9 0.0 5120 -16 0.0 6450 -18.1 0.0 8130 -20.1 0.0 10200 -22.1 0.0 12900 -24.2 0.0 16300 -26.2 0.0 20500 -28.2 0.0 As you can see, the response problems you predict simply do not happen. Now, as to the assertion of there being a "short circuit" across the amplifier, let's look at the impedance: Frequency Impedance ---------- --------- 20 Hz 8 Ohms 25.2 8 31.7 7.99 40 7.99 50.4 7.98 63.5 7.97 80 7.96 101 7.93 127 7.89 160 7.83 202 7.74 254 7.61 320 7.41 403 7.16 508 6.84 640 6.51 806 6.25 1020 6.15 1280 6.26 1610 6.53 2030 6.87 2560 7.18 3230 7.43 4060 7.62 5120 7.75 6450 7.84 8130 7.9 10200 7.93 12900 7.96 16300 7.97 20500 7.98 At no point does the impedance EVER drop below 6 ohms. Hardly a short as you claim. Let's even look at DC, where the inductor impedance is 0 and the capacitor impedance is infinite: the imepdance of the total cricuit is that of the woofer. At infinite frequency, where the impedance of the capacitor is 0 and the inductor is infinite, the impedance is that of the tweeter. |
#29
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Dynaco A25 XL Speaker - Need crossover diagram.
"Tim Padrick" wrote in message ...
Not so. In a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Too bad you didn't try to understand or analyze the circuit. If you were to put JUST a tweeter and JUST an inductor in parallel across an amp, you'd be right, but that's VERY clearly, from the topology above, NOT what is happening. You cannot look at a circuit and simpy pick little pieces of it and expect a quick analysis based on one piece to give you a coherent picture of the whole. Let's, in fact, do a more complete analysis and see what is REALLY happening We'll make some simplifying assumption just to make the analysis easier: we'll replace XWoofer and XTweeter with resistive loads RWoofer and RTweeter. Start at frequencies well below the crossover point. At these frequencies the impedance of shunt capacitor CWoof is very high, and that of the shunt inductor LTweet is very low. As a result, the current flows through the woofer leg (RWoofer) and through the inductor LTweet) And the amplifier sees, essentially, the woofer as the load. Now, at high frequencies well ABOVE the crossover point, the impedance of the shunt capacitor CWoof is very low and that of the shunt inductor LTweet is very high. As a result, the current flows through the shunt capacitor (CWoofer), bypassing the woofer and flowing through the tweeter leg. And the amplifier sees, essentially, the tweeter as the load. Around the crossover, the impedance of the two shunt reactances LTweet and CWoof) are about the same, and are also about the same as the impedances of the woofer and tweeter (assuming we don't pick values out of thin air, like I did). In such a condition, equal amounts of the current flow through each leg of the mesh, meaning the power to the woofer and tweeter are about the same. And the load seen by the amplifier is the parallel combination of the woofer mesh and tweeter mesh. Contrary to your analysis at NO point does the amplifier EVER see a short circuit. Let's in fact do a more precise analysis. I have adjusted the values to something a bit more practical, aiming for a 1 kHz crossover. Here's the new circuit: * Series crossover analysis Vin 1 0 AC SIN 1.0 0.0 CWoof 1 2 25UF RWoof 1 2 8 LTweet 2 0 1MH RTweet 2 0 8 .AC OCT 3 20 20K .PRINT AC VDB(1, 2) VDB(2,0) .END Now, here's the output response across the woofer terminals and the tweeter terminals, plotted every 1/3 octave: Frequency Woofer Tweeter Response Response ---------- -------- -------- 20 Hz 0.0 dB -36.1 dB 25.2 0.0 -34.1 31.7 0.0 -32.1 40 0.0 -30.1 50.4 0.0 -28 63.5 0.0 -26 80 0.0 -24 101 0.0 -22 127 0.0 -19.9 160 0.0 -17.9 202 0.0 -15.8 254 0.0 -13.7 320 0.0 -11.6 403 0.0 -9.4 508 -0.1 -7.3 640 -0.4 -5.2 806 -0.9 -3.3 1020 -1.9 -1.8 1280 -3.4 -0.9 1610 -5.3 -0.3 2030 -7.4 -0.1 2560 -9.6 -0.0 3230 -11.8 0.0 4060 -13.9 0.0 5120 -16 0.0 6450 -18.1 0.0 8130 -20.1 0.0 10200 -22.1 0.0 12900 -24.2 0.0 16300 -26.2 0.0 20500 -28.2 0.0 As you can see, the response problems you predict simply do not happen. Now, as to the assertion of there being a "short circuit" across the amplifier, let's look at the impedance: Frequency Impedance ---------- --------- 20 Hz 8 Ohms 25.2 8 31.7 7.99 40 7.99 50.4 7.98 63.5 7.97 80 7.96 101 7.93 127 7.89 160 7.83 202 7.74 254 7.61 320 7.41 403 7.16 508 6.84 640 6.51 806 6.25 1020 6.15 1280 6.26 1610 6.53 2030 6.87 2560 7.18 3230 7.43 4060 7.62 5120 7.75 6450 7.84 8130 7.9 10200 7.93 12900 7.96 16300 7.97 20500 7.98 At no point does the impedance EVER drop below 6 ohms. Hardly a short as you claim. Let's even look at DC, where the inductor impedance is 0 and the capacitor impedance is infinite: the imepdance of the total cricuit is that of the woofer. At infinite frequency, where the impedance of the capacitor is 0 and the inductor is infinite, the impedance is that of the tweeter. |
#30
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Dynaco A25 XL Speaker - Need crossover diagram.
"Dick Pierce" wrote in message
om "Tim Padrick" wrote in message ... Not so. In a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Too bad you didn't try to understand or analyze the circuit. If you were to put JUST a tweeter and JUST an inductor in parallel across an amp, you'd be right, but that's VERY clearly, from the topology above, NOT what is happening. You cannot look at a circuit and simpy pick little pieces of it and expect a quick analysis based on one piece to give you a coherent picture of the whole. Let's, in fact, do a more complete analysis and see what is REALLY happening We'll make some simplifying assumption just to make the analysis easier: we'll replace XWoofer and XTweeter with resistive loads RWoofer and RTweeter. Start at frequencies well below the crossover point. At these frequencies the impedance of shunt capacitor CWoof is very high, and that of the shunt inductor LTweet is very low. As a result, the current flows through the woofer leg (RWoofer) and through the inductor LTweet) And the amplifier sees, essentially, the woofer as the load. Now, at high frequencies well ABOVE the crossover point, the impedance of the shunt capacitor CWoof is very low and that of the shunt inductor LTweet is very high. As a result, the current flows through the shunt capacitor (CWoofer), bypassing the woofer and flowing through the tweeter leg. And the amplifier sees, essentially, the tweeter as the load. Around the crossover, the impedance of the two shunt reactances LTweet and CWoof) are about the same, and are also about the same as the impedances of the woofer and tweeter (assuming we don't pick values out of thin air, like I did). In such a condition, equal amounts of the current flow through each leg of the mesh, meaning the power to the woofer and tweeter are about the same. And the load seen by the amplifier is the parallel combination of the woofer mesh and tweeter mesh. Contrary to your analysis at NO point does the amplifier EVER see a short circuit. Let's in fact do a more precise analysis. I have adjusted the values to something a bit more practical, aiming for a 1 kHz crossover. Here's the new circuit: * Series crossover analysis Vin 1 0 AC SIN 1.0 0.0 CWoof 1 2 25UF RWoof 1 2 8 LTweet 2 0 1MH RTweet 2 0 8 .AC OCT 3 20 20K .PRINT AC VDB(1, 2) VDB(2,0) .END Now, here's the output response across the woofer terminals and the tweeter terminals, plotted every 1/3 octave: Frequency Woofer Tweeter Response Response ---------- -------- -------- 20 Hz 0.0 dB -36.1 dB 25.2 0.0 -34.1 31.7 0.0 -32.1 40 0.0 -30.1 50.4 0.0 -28 63.5 0.0 -26 80 0.0 -24 101 0.0 -22 127 0.0 -19.9 160 0.0 -17.9 202 0.0 -15.8 254 0.0 -13.7 320 0.0 -11.6 403 0.0 -9.4 508 -0.1 -7.3 640 -0.4 -5.2 806 -0.9 -3.3 1020 -1.9 -1.8 1280 -3.4 -0.9 1610 -5.3 -0.3 2030 -7.4 -0.1 2560 -9.6 -0.0 3230 -11.8 0.0 4060 -13.9 0.0 5120 -16 0.0 6450 -18.1 0.0 8130 -20.1 0.0 10200 -22.1 0.0 12900 -24.2 0.0 16300 -26.2 0.0 20500 -28.2 0.0 As you can see, the response problems you predict simply do not happen. Now, as to the assertion of there being a "short circuit" across the amplifier, let's look at the impedance: Frequency Impedance ---------- --------- 20 Hz 8 Ohms 25.2 8 31.7 7.99 40 7.99 50.4 7.98 63.5 7.97 80 7.96 101 7.93 127 7.89 160 7.83 202 7.74 254 7.61 320 7.41 403 7.16 508 6.84 640 6.51 806 6.25 1020 6.15 1280 6.26 1610 6.53 2030 6.87 2560 7.18 3230 7.43 4060 7.62 5120 7.75 6450 7.84 8130 7.9 10200 7.93 12900 7.96 16300 7.97 20500 7.98 At no point does the impedance EVER drop below 6 ohms. Hardly a short as you claim. Let's even look at DC, where the inductor impedance is 0 and the capacitor impedance is infinite: the imepdance of the total cricuit is that of the woofer. At infinite frequency, where the impedance of the capacitor is 0 and the inductor is infinite, the impedance is that of the tweeter. Thanks for the lesson in reciprocity! |
#31
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Dynaco A25 XL Speaker - Need crossover diagram.
"Dick Pierce" wrote in message
om "Tim Padrick" wrote in message ... Not so. In a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Too bad you didn't try to understand or analyze the circuit. If you were to put JUST a tweeter and JUST an inductor in parallel across an amp, you'd be right, but that's VERY clearly, from the topology above, NOT what is happening. You cannot look at a circuit and simpy pick little pieces of it and expect a quick analysis based on one piece to give you a coherent picture of the whole. Let's, in fact, do a more complete analysis and see what is REALLY happening We'll make some simplifying assumption just to make the analysis easier: we'll replace XWoofer and XTweeter with resistive loads RWoofer and RTweeter. Start at frequencies well below the crossover point. At these frequencies the impedance of shunt capacitor CWoof is very high, and that of the shunt inductor LTweet is very low. As a result, the current flows through the woofer leg (RWoofer) and through the inductor LTweet) And the amplifier sees, essentially, the woofer as the load. Now, at high frequencies well ABOVE the crossover point, the impedance of the shunt capacitor CWoof is very low and that of the shunt inductor LTweet is very high. As a result, the current flows through the shunt capacitor (CWoofer), bypassing the woofer and flowing through the tweeter leg. And the amplifier sees, essentially, the tweeter as the load. Around the crossover, the impedance of the two shunt reactances LTweet and CWoof) are about the same, and are also about the same as the impedances of the woofer and tweeter (assuming we don't pick values out of thin air, like I did). In such a condition, equal amounts of the current flow through each leg of the mesh, meaning the power to the woofer and tweeter are about the same. And the load seen by the amplifier is the parallel combination of the woofer mesh and tweeter mesh. Contrary to your analysis at NO point does the amplifier EVER see a short circuit. Let's in fact do a more precise analysis. I have adjusted the values to something a bit more practical, aiming for a 1 kHz crossover. Here's the new circuit: * Series crossover analysis Vin 1 0 AC SIN 1.0 0.0 CWoof 1 2 25UF RWoof 1 2 8 LTweet 2 0 1MH RTweet 2 0 8 .AC OCT 3 20 20K .PRINT AC VDB(1, 2) VDB(2,0) .END Now, here's the output response across the woofer terminals and the tweeter terminals, plotted every 1/3 octave: Frequency Woofer Tweeter Response Response ---------- -------- -------- 20 Hz 0.0 dB -36.1 dB 25.2 0.0 -34.1 31.7 0.0 -32.1 40 0.0 -30.1 50.4 0.0 -28 63.5 0.0 -26 80 0.0 -24 101 0.0 -22 127 0.0 -19.9 160 0.0 -17.9 202 0.0 -15.8 254 0.0 -13.7 320 0.0 -11.6 403 0.0 -9.4 508 -0.1 -7.3 640 -0.4 -5.2 806 -0.9 -3.3 1020 -1.9 -1.8 1280 -3.4 -0.9 1610 -5.3 -0.3 2030 -7.4 -0.1 2560 -9.6 -0.0 3230 -11.8 0.0 4060 -13.9 0.0 5120 -16 0.0 6450 -18.1 0.0 8130 -20.1 0.0 10200 -22.1 0.0 12900 -24.2 0.0 16300 -26.2 0.0 20500 -28.2 0.0 As you can see, the response problems you predict simply do not happen. Now, as to the assertion of there being a "short circuit" across the amplifier, let's look at the impedance: Frequency Impedance ---------- --------- 20 Hz 8 Ohms 25.2 8 31.7 7.99 40 7.99 50.4 7.98 63.5 7.97 80 7.96 101 7.93 127 7.89 160 7.83 202 7.74 254 7.61 320 7.41 403 7.16 508 6.84 640 6.51 806 6.25 1020 6.15 1280 6.26 1610 6.53 2030 6.87 2560 7.18 3230 7.43 4060 7.62 5120 7.75 6450 7.84 8130 7.9 10200 7.93 12900 7.96 16300 7.97 20500 7.98 At no point does the impedance EVER drop below 6 ohms. Hardly a short as you claim. Let's even look at DC, where the inductor impedance is 0 and the capacitor impedance is infinite: the imepdance of the total cricuit is that of the woofer. At infinite frequency, where the impedance of the capacitor is 0 and the inductor is infinite, the impedance is that of the tweeter. Thanks for the lesson in reciprocity! |
#32
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Dynaco A25 XL Speaker - Need crossover diagram.
"Dick Pierce" wrote in message
om "Tim Padrick" wrote in message ... Not so. In a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Too bad you didn't try to understand or analyze the circuit. If you were to put JUST a tweeter and JUST an inductor in parallel across an amp, you'd be right, but that's VERY clearly, from the topology above, NOT what is happening. You cannot look at a circuit and simpy pick little pieces of it and expect a quick analysis based on one piece to give you a coherent picture of the whole. Let's, in fact, do a more complete analysis and see what is REALLY happening We'll make some simplifying assumption just to make the analysis easier: we'll replace XWoofer and XTweeter with resistive loads RWoofer and RTweeter. Start at frequencies well below the crossover point. At these frequencies the impedance of shunt capacitor CWoof is very high, and that of the shunt inductor LTweet is very low. As a result, the current flows through the woofer leg (RWoofer) and through the inductor LTweet) And the amplifier sees, essentially, the woofer as the load. Now, at high frequencies well ABOVE the crossover point, the impedance of the shunt capacitor CWoof is very low and that of the shunt inductor LTweet is very high. As a result, the current flows through the shunt capacitor (CWoofer), bypassing the woofer and flowing through the tweeter leg. And the amplifier sees, essentially, the tweeter as the load. Around the crossover, the impedance of the two shunt reactances LTweet and CWoof) are about the same, and are also about the same as the impedances of the woofer and tweeter (assuming we don't pick values out of thin air, like I did). In such a condition, equal amounts of the current flow through each leg of the mesh, meaning the power to the woofer and tweeter are about the same. And the load seen by the amplifier is the parallel combination of the woofer mesh and tweeter mesh. Contrary to your analysis at NO point does the amplifier EVER see a short circuit. Let's in fact do a more precise analysis. I have adjusted the values to something a bit more practical, aiming for a 1 kHz crossover. Here's the new circuit: * Series crossover analysis Vin 1 0 AC SIN 1.0 0.0 CWoof 1 2 25UF RWoof 1 2 8 LTweet 2 0 1MH RTweet 2 0 8 .AC OCT 3 20 20K .PRINT AC VDB(1, 2) VDB(2,0) .END Now, here's the output response across the woofer terminals and the tweeter terminals, plotted every 1/3 octave: Frequency Woofer Tweeter Response Response ---------- -------- -------- 20 Hz 0.0 dB -36.1 dB 25.2 0.0 -34.1 31.7 0.0 -32.1 40 0.0 -30.1 50.4 0.0 -28 63.5 0.0 -26 80 0.0 -24 101 0.0 -22 127 0.0 -19.9 160 0.0 -17.9 202 0.0 -15.8 254 0.0 -13.7 320 0.0 -11.6 403 0.0 -9.4 508 -0.1 -7.3 640 -0.4 -5.2 806 -0.9 -3.3 1020 -1.9 -1.8 1280 -3.4 -0.9 1610 -5.3 -0.3 2030 -7.4 -0.1 2560 -9.6 -0.0 3230 -11.8 0.0 4060 -13.9 0.0 5120 -16 0.0 6450 -18.1 0.0 8130 -20.1 0.0 10200 -22.1 0.0 12900 -24.2 0.0 16300 -26.2 0.0 20500 -28.2 0.0 As you can see, the response problems you predict simply do not happen. Now, as to the assertion of there being a "short circuit" across the amplifier, let's look at the impedance: Frequency Impedance ---------- --------- 20 Hz 8 Ohms 25.2 8 31.7 7.99 40 7.99 50.4 7.98 63.5 7.97 80 7.96 101 7.93 127 7.89 160 7.83 202 7.74 254 7.61 320 7.41 403 7.16 508 6.84 640 6.51 806 6.25 1020 6.15 1280 6.26 1610 6.53 2030 6.87 2560 7.18 3230 7.43 4060 7.62 5120 7.75 6450 7.84 8130 7.9 10200 7.93 12900 7.96 16300 7.97 20500 7.98 At no point does the impedance EVER drop below 6 ohms. Hardly a short as you claim. Let's even look at DC, where the inductor impedance is 0 and the capacitor impedance is infinite: the imepdance of the total cricuit is that of the woofer. At infinite frequency, where the impedance of the capacitor is 0 and the inductor is infinite, the impedance is that of the tweeter. Thanks for the lesson in reciprocity! |
#33
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Dynaco A25 XL Speaker - Need crossover diagram.
"Dick Pierce" wrote in message
om "Tim Padrick" wrote in message ... Not so. In a series-pass crossover, the inductor would be in parallel with the tweeter and the capacitor in series with the woofer. Two SPICE files indicate the topological differences. First, the more common parallel model (assume MyWoofer and MyTweeter are both appropriate Spice sub circuit models of the woofer and tweeter, and ignore the fact that the values may or may not be appropriate): * Parallel crossover net list Vin 1 0 AC SIN 1.0 0.0 Lwoof 1 2 1MH Xwoof 2 0 MyWoofer Ctweet 1 3 8UF XTweet 3 0 MyTweeter Now, the same as a series-pass model: * Series crossover net list Vin 1 0 AC SIN 1.0 0.0 Cwoof 1 2 8UF Xwoof 1 2 MyWoofer LTweet 2 0 1MH XTweet 2 0 MyTweeter An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Too bad you didn't try to understand or analyze the circuit. If you were to put JUST a tweeter and JUST an inductor in parallel across an amp, you'd be right, but that's VERY clearly, from the topology above, NOT what is happening. You cannot look at a circuit and simpy pick little pieces of it and expect a quick analysis based on one piece to give you a coherent picture of the whole. Let's, in fact, do a more complete analysis and see what is REALLY happening We'll make some simplifying assumption just to make the analysis easier: we'll replace XWoofer and XTweeter with resistive loads RWoofer and RTweeter. Start at frequencies well below the crossover point. At these frequencies the impedance of shunt capacitor CWoof is very high, and that of the shunt inductor LTweet is very low. As a result, the current flows through the woofer leg (RWoofer) and through the inductor LTweet) And the amplifier sees, essentially, the woofer as the load. Now, at high frequencies well ABOVE the crossover point, the impedance of the shunt capacitor CWoof is very low and that of the shunt inductor LTweet is very high. As a result, the current flows through the shunt capacitor (CWoofer), bypassing the woofer and flowing through the tweeter leg. And the amplifier sees, essentially, the tweeter as the load. Around the crossover, the impedance of the two shunt reactances LTweet and CWoof) are about the same, and are also about the same as the impedances of the woofer and tweeter (assuming we don't pick values out of thin air, like I did). In such a condition, equal amounts of the current flow through each leg of the mesh, meaning the power to the woofer and tweeter are about the same. And the load seen by the amplifier is the parallel combination of the woofer mesh and tweeter mesh. Contrary to your analysis at NO point does the amplifier EVER see a short circuit. Let's in fact do a more precise analysis. I have adjusted the values to something a bit more practical, aiming for a 1 kHz crossover. Here's the new circuit: * Series crossover analysis Vin 1 0 AC SIN 1.0 0.0 CWoof 1 2 25UF RWoof 1 2 8 LTweet 2 0 1MH RTweet 2 0 8 .AC OCT 3 20 20K .PRINT AC VDB(1, 2) VDB(2,0) .END Now, here's the output response across the woofer terminals and the tweeter terminals, plotted every 1/3 octave: Frequency Woofer Tweeter Response Response ---------- -------- -------- 20 Hz 0.0 dB -36.1 dB 25.2 0.0 -34.1 31.7 0.0 -32.1 40 0.0 -30.1 50.4 0.0 -28 63.5 0.0 -26 80 0.0 -24 101 0.0 -22 127 0.0 -19.9 160 0.0 -17.9 202 0.0 -15.8 254 0.0 -13.7 320 0.0 -11.6 403 0.0 -9.4 508 -0.1 -7.3 640 -0.4 -5.2 806 -0.9 -3.3 1020 -1.9 -1.8 1280 -3.4 -0.9 1610 -5.3 -0.3 2030 -7.4 -0.1 2560 -9.6 -0.0 3230 -11.8 0.0 4060 -13.9 0.0 5120 -16 0.0 6450 -18.1 0.0 8130 -20.1 0.0 10200 -22.1 0.0 12900 -24.2 0.0 16300 -26.2 0.0 20500 -28.2 0.0 As you can see, the response problems you predict simply do not happen. Now, as to the assertion of there being a "short circuit" across the amplifier, let's look at the impedance: Frequency Impedance ---------- --------- 20 Hz 8 Ohms 25.2 8 31.7 7.99 40 7.99 50.4 7.98 63.5 7.97 80 7.96 101 7.93 127 7.89 160 7.83 202 7.74 254 7.61 320 7.41 403 7.16 508 6.84 640 6.51 806 6.25 1020 6.15 1280 6.26 1610 6.53 2030 6.87 2560 7.18 3230 7.43 4060 7.62 5120 7.75 6450 7.84 8130 7.9 10200 7.93 12900 7.96 16300 7.97 20500 7.98 At no point does the impedance EVER drop below 6 ohms. Hardly a short as you claim. Let's even look at DC, where the inductor impedance is 0 and the capacitor impedance is infinite: the imepdance of the total cricuit is that of the woofer. At infinite frequency, where the impedance of the capacitor is 0 and the inductor is infinite, the impedance is that of the tweeter. Thanks for the lesson in reciprocity! |
#34
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Dynaco A25 XL Speaker - Need crossover diagram.
"Arny Krueger" wrote in message ...
"Tim Padrick" wrote in message An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Agreed, and that leaves some non-simple problems to solve. No it doesn't. AFAIK the very few commercial designs with an inductor in parallel with the tweeter use a tweeter that is more efficient than the woofer, and put a resistor in series with the inductor/tweeter combination. Still not a pretty picture. Sorry, but you're both pretty clueless as to what was described. This is hardly an uncommon crossover design, and was fairly well described 3 decades and more ago, for example, Small, R. H., "Constant Voltage Crossover Design," Proc IREE Australia vol 31 (1970), reprinted in J. Audio Eng. Soc. 1971 Jan: "the series network in Fig 10b [EXACTLY the topology I described] in inherently advantageous because tolerances in the component values, both in the crossover and in the termination, will have no effect on the total network voltage response. Because the drivers are connected in series across the amplifier output, the sum of the voice- coil voltages must always be equal to the driving voltage." As both explained AND demonstrated in my other response to these assertions, it is hardly a "non-simple problem," indeed, it is no problem at all, having some significant advantages. How about actually LOOKING at the circuit and UNDERSTANDING it? |
#35
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Dynaco A25 XL Speaker - Need crossover diagram.
"Arny Krueger" wrote in message ...
"Tim Padrick" wrote in message An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Agreed, and that leaves some non-simple problems to solve. No it doesn't. AFAIK the very few commercial designs with an inductor in parallel with the tweeter use a tweeter that is more efficient than the woofer, and put a resistor in series with the inductor/tweeter combination. Still not a pretty picture. Sorry, but you're both pretty clueless as to what was described. This is hardly an uncommon crossover design, and was fairly well described 3 decades and more ago, for example, Small, R. H., "Constant Voltage Crossover Design," Proc IREE Australia vol 31 (1970), reprinted in J. Audio Eng. Soc. 1971 Jan: "the series network in Fig 10b [EXACTLY the topology I described] in inherently advantageous because tolerances in the component values, both in the crossover and in the termination, will have no effect on the total network voltage response. Because the drivers are connected in series across the amplifier output, the sum of the voice- coil voltages must always be equal to the driving voltage." As both explained AND demonstrated in my other response to these assertions, it is hardly a "non-simple problem," indeed, it is no problem at all, having some significant advantages. How about actually LOOKING at the circuit and UNDERSTANDING it? |
#36
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Dynaco A25 XL Speaker - Need crossover diagram.
"Arny Krueger" wrote in message ...
"Tim Padrick" wrote in message An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Agreed, and that leaves some non-simple problems to solve. No it doesn't. AFAIK the very few commercial designs with an inductor in parallel with the tweeter use a tweeter that is more efficient than the woofer, and put a resistor in series with the inductor/tweeter combination. Still not a pretty picture. Sorry, but you're both pretty clueless as to what was described. This is hardly an uncommon crossover design, and was fairly well described 3 decades and more ago, for example, Small, R. H., "Constant Voltage Crossover Design," Proc IREE Australia vol 31 (1970), reprinted in J. Audio Eng. Soc. 1971 Jan: "the series network in Fig 10b [EXACTLY the topology I described] in inherently advantageous because tolerances in the component values, both in the crossover and in the termination, will have no effect on the total network voltage response. Because the drivers are connected in series across the amplifier output, the sum of the voice- coil voltages must always be equal to the driving voltage." As both explained AND demonstrated in my other response to these assertions, it is hardly a "non-simple problem," indeed, it is no problem at all, having some significant advantages. How about actually LOOKING at the circuit and UNDERSTANDING it? |
#37
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Dynaco A25 XL Speaker - Need crossover diagram.
"Arny Krueger" wrote in message ...
"Tim Padrick" wrote in message An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Agreed, and that leaves some non-simple problems to solve. No it doesn't. AFAIK the very few commercial designs with an inductor in parallel with the tweeter use a tweeter that is more efficient than the woofer, and put a resistor in series with the inductor/tweeter combination. Still not a pretty picture. Sorry, but you're both pretty clueless as to what was described. This is hardly an uncommon crossover design, and was fairly well described 3 decades and more ago, for example, Small, R. H., "Constant Voltage Crossover Design," Proc IREE Australia vol 31 (1970), reprinted in J. Audio Eng. Soc. 1971 Jan: "the series network in Fig 10b [EXACTLY the topology I described] in inherently advantageous because tolerances in the component values, both in the crossover and in the termination, will have no effect on the total network voltage response. Because the drivers are connected in series across the amplifier output, the sum of the voice- coil voltages must always be equal to the driving voltage." As both explained AND demonstrated in my other response to these assertions, it is hardly a "non-simple problem," indeed, it is no problem at all, having some significant advantages. How about actually LOOKING at the circuit and UNDERSTANDING it? |
#38
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Dynaco A25 XL Speaker - Need crossover diagram.
"Dick Pierce" wrote in message
om "Arny Krueger" wrote in message ... "Tim Padrick" wrote in message An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Agreed, and that leaves some non-simple problems to solve. No it doesn't. Please see my post from 8:23 EST this morning. |
#39
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Dynaco A25 XL Speaker - Need crossover diagram.
"Dick Pierce" wrote in message
om "Arny Krueger" wrote in message ... "Tim Padrick" wrote in message An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Agreed, and that leaves some non-simple problems to solve. No it doesn't. Please see my post from 8:23 EST this morning. |
#40
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Dynaco A25 XL Speaker - Need crossover diagram.
"Dick Pierce" wrote in message
om "Arny Krueger" wrote in message ... "Tim Padrick" wrote in message An inductor in parallel with a tweeter, without a series capacitor, would be seen by the amp as a short at low frequencies. A cap in series with a woofer would roll off the low frequencies. Agreed, and that leaves some non-simple problems to solve. No it doesn't. Please see my post from 8:23 EST this morning. |
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