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#1
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Greetings;
Does anyone know offhand the nominal impedance of Magnepan MG 1's? Has anyone bothered to do an impedance check across the audio range? Thanks for any info, before I hook up an impedance bridge, I thought I'd ask. I lost the literature that came with the speakers and I'm curious what the factory says these things are. Stan K |
#2
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stan wrote:
Greetings; Does anyone know offhand the nominal impedance of Magnepan MG 1's? Has anyone bothered to do an impedance check across the audio range? Thanks for any info, before I hook up an impedance bridge, I thought I'd ask. I lost the literature that came with the speakers and I'm curious what the factory says these things are. Stan K I think most Maggies were 4ohm. Some were ruler flat. |
#3
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Thanks WB, I'll start there.On Wed, 08 Mar 2006 01:45:56 GMT, wß
wrote: stan wrote: Greetings; Does anyone know offhand the nominal impedance of Magnepan MG 1's? Has anyone bothered to do an impedance check across the audio range? Thanks for any info, before I hook up an impedance bridge, I thought I'd ask. I lost the literature that came with the speakers and I'm curious what the factory says these things are. Stan K I think most Maggies were 4ohm. Some were ruler flat. |
#4
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![]() "stan" wrote in message ... Greetings; Does anyone know offhand the nominal impedance of Magnepan MG 1's? Has anyone bothered to do an impedance check across the audio range? **Maggies all exhibit a pretty much resistive load of 4 Ohms. -- Trevor Wilson www.rageaudio.com.au |
#5
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Thanks Trevor, you back up what others have said, and what I remember.
It's the "what I remember" part that I no longer trust, so to have you guys refresh my memory gives me some confidence.On Wed, 8 Mar 2006 13:18:42 +1100, "Trevor Wilson" wrote: "stan" wrote in message .. . Greetings; Does anyone know offhand the nominal impedance of Magnepan MG 1's? Has anyone bothered to do an impedance check across the audio range? **Maggies all exhibit a pretty much resistive load of 4 Ohms. |
#6
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Different models have different impedances.
The impedance of a Magnepan speaker is just about pure resistance and therefore is very flat over the entire audio range. It is little more than hundreds of feet of stainless steel wire and it isn't wond in a typical coil. James. ![]() "stan" wrote in message ... Greetings; Does anyone know offhand the nominal impedance of Magnepan MG 1's? Has anyone bothered to do an impedance check across the audio range? Thanks for any info, before I hook up an impedance bridge, I thought I'd ask. I lost the literature that came with the speakers and I'm curious what the factory says these things are. Stan K |
#7
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Well, there are two elements, as well as a 1st order crossover, so I'm
not sure it's as clean cut as it appears, but the 5 ohm nominal that the other gentleman mentioned seems to be what I remember about this particular model. Thanks for all the responses, you guys have been helpful. Stan K A couple of links to some pics of mine www.athenet.net/~kots6177/stereo1.jpg www.athenet.net/~kots6177/stereo2.jpg On Wed, 08 Mar 2006 19:44:30 GMT, "James Lehman" wrote: Different models have different impedances. The impedance of a Magnepan speaker is just about pure resistance and therefore is very flat over the entire audio range. It is little more than hundreds of feet of stainless steel wire and it isn't wond in a typical coil. James. ![]() "stan" wrote in message .. . Greetings; Does anyone know offhand the nominal impedance of Magnepan MG 1's? Has anyone bothered to do an impedance check across the audio range? Thanks for any info, before I hook up an impedance bridge, I thought I'd ask. I lost the literature that came with the speakers and I'm curious what the factory says these things are. Stan K |
#8
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![]() stan wrote: On Wed, 08 Mar 2006 19:44:30 GMT, "James Lehman" wrote: Different models have different impedances. The impedance of a Magnepan speaker is just about pure resistance and therefore is very flat over the entire audio range. Actually, no. The MG3.6, for example, shows an impedance that varies from a low of about 3.5 ohms around 10 kHz to a maximum of almost three times that around 1600 Hz. Nor is it purely resistive or even just about, as the phas angle of the impedance swings between about -25 to +25 degrees over the 20-20,000Hz range. The MG1.6 varies from a low of about 4.2 ohms to a maximum of 19 ohms at about 600 Hz, and it is also not "purely resistive," with an impedance phase angle that swings between -30 and +40 degrees. It is little more than hundreds of feet of stainless steel wire and it isn't wo[u]nd in a typical coil. That may be, but it still exhibits inductance at high frequencies, as exhibit by the fact that the impedance phase angle goes positive and stays there at high frequencies. The fact that it "isn't wound in a typical coil" doesn't exempt it from inductive reactance. Well, there are two elements, as well as a 1st order crossover, so I'm not sure it's as clean cut as it appears, Exactly. |
#10
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![]() stan wrote: On 9 Mar 2006 08:49:26 -0800, wrote: Actually, no. The MG3.6, for example, shows an impedance that varies from a low of about 3.5 ohms around 10 kHz to a maximum of almost three times that around 1600 Hz. Nor is it purely resistive or even just about, as the phas angle of the impedance swings between about -25 to +25 degrees over the 20-20,000Hz range. The MG1.6 varies from a low of about 4.2 ohms to a maximum of 19 ohms at about 600 Hz, and it is also not "purely resistive," with an impedance phase angle that swings between -30 and +40 degrees. What you say makes inherent sense, without actually measuring. Hmm, I'm not sure why it would make "inherent" sense. Did you actually bother to measure the phase angle, or did you find this information somewhere,? The answer is yes, yes and you don't have to. I have in fact measured the phase, the information can be found elsewhere (try a google search for "magnepan impedance curve"), and you don't have to measure the impedance phase angle to derive it . SInce the impedance vs frequency represents a minimum-phase response, one can unambiguously derive the phase angle from the impedance magnitude via the Hilbert transform. |
#11
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The reason it makes inherent sense is because any crossover will lead
to phase shifting, and any current through a wire in the presence of a magnetic field will also lead to phase shift.On 9 Mar 2006 13:26:13 -0800, wrote: stan wrote: On 9 Mar 2006 08:49:26 -0800, wrote: Actually, no. The MG3.6, for example, shows an impedance that varies from a low of about 3.5 ohms around 10 kHz to a maximum of almost three times that around 1600 Hz. Nor is it purely resistive or even just about, as the phas angle of the impedance swings between about -25 to +25 degrees over the 20-20,000Hz range. The MG1.6 varies from a low of about 4.2 ohms to a maximum of 19 ohms at about 600 Hz, and it is also not "purely resistive," with an impedance phase angle that swings between -30 and +40 degrees. What you say makes inherent sense, without actually measuring. Hmm, I'm not sure why it would make "inherent" sense. Did you actually bother to measure the phase angle, or did you find this information somewhere,? The answer is yes, yes and you don't have to. I have in fact measured the phase, the information can be found elsewhere (try a google search for "magnepan impedance curve"), and you don't have to measure the impedance phase angle to derive it . SInce the impedance vs frequency represents a minimum-phase response, one can unambiguously derive the phase angle from the impedance magnitude via the Hilbert transform. |
#12
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![]() stan wrote: What you say makes inherent sense, without actually measuring. Hmm, I'm not sure why it would make "inherent" sense. The reason it makes inherent sense is because any crossover will lead to phase shifting, No, the presence of a crossover, in and of itself, does not lead to "phase shifting." It's simply the presence of reactances in the impedance. There are no capacitors or inductors per se in a woofer, yet the impedance will at some freqencies show some degree of capactive reactance with an attendant negative phase angle, and at other frequencies will show some degree of inductive reactiance, with its attendant positive pahse angle, and at other frequencies, it will show no reactance, and the phase angle will be 0. And it is quite possible to build a crossver whose input impedance exhibits no reactance and thus the impedance phase shift is zero. It's also possible to build a complex conjugate for the impedance with the net result that the input impedance it effectively resistive. and any current through a wire in the presence of a magnetic field will also lead to phase shift. Has absolutely NOTHING to do with a current flowing in the presence of a magnetic field. Send a million amps DC down a wire in a million tesla field, and there will be no inductance whatsoever. The inductance arises as a result of the rate change of current causing a rate change in the induced field which in turn induces a current back into the wire. It basically requires a net change in current flow over an area. The presence of an extant magnetic field will have no effect. |
#13
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I was talking an audio application, ie, AC, not DC, just for
clarification. Your point on the woofer is well taken, and applies to all the other components as well, they all have resistance, capacitance, and inductance, in an AC signal. On 9 Mar 2006 14:58:34 -0800, wrote: stan wrote: What you say makes inherent sense, without actually measuring. Hmm, I'm not sure why it would make "inherent" sense. The reason it makes inherent sense is because any crossover will lead to phase shifting, No, the presence of a crossover, in and of itself, does not lead to "phase shifting." It's simply the presence of reactances in the impedance. There are no capacitors or inductors per se in a woofer, yet the impedance will at some freqencies show some degree of capactive reactance with an attendant negative phase angle, and at other frequencies will show some degree of inductive reactiance, with its attendant positive pahse angle, and at other frequencies, it will show no reactance, and the phase angle will be 0. And it is quite possible to build a crossver whose input impedance exhibits no reactance and thus the impedance phase shift is zero. It's also possible to build a complex conjugate for the impedance with the net result that the input impedance it effectively resistive. and any current through a wire in the presence of a magnetic field will also lead to phase shift. Has absolutely NOTHING to do with a current flowing in the presence of a magnetic field. Send a million amps DC down a wire in a million tesla field, and there will be no inductance whatsoever. The inductance arises as a result of the rate change of current causing a rate change in the induced field which in turn induces a current back into the wire. It basically requires a net change in current flow over an area. The presence of an extant magnetic field will have no effect. |
#14
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![]() wrote in message oups.com... Has absolutely NOTHING to do with a current flowing in the presence of a magnetic field. Send a million amps DC down a wire in a million tesla field, and there will be no inductance whatsoever. **Not quite, but, for all practical purposes, you are correct. ALL wire exhibits inductance. Send that MA down a 1 Metre length of wire, with a 1pS rise time and you'll see what I mean. -- Trevor Wilson www.rageaudio.com.au |
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