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#1
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mono speaker cable to stereo RCA
Does anyone have directions on how to create a mono speaker wire to
stereo rca cable. I am trying to hook a mono radio, in a volvo 122s, to a new amplifier. I realize the signal will still be mono, but I would like it to come out on both the left and right speakers of my car. Can I determine which speaker wires are - and +, using a multimeter? Thanks, lollipop |
#2
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"lollipop" wrote in message oups.com... Does anyone have directions on how to create a mono speaker wire to stereo rca cable. I am trying to hook a mono radio, in a volvo 122s, to a new amplifier. I realize the signal will still be mono, but I would like it to come out on both the left and right speakers of my car. Can I determine which speaker wires are - and +, using a multimeter? Thanks, lollipop No, but if it's mono, it doesn't matter which is + and which is -. Polarity problems only happen when there's more than one speaker. |
#3
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You need a speaker-to-line level converter. They are available from most car
audio stores and electronic hobbie stores like Radio Shack. I believe even Walmart sells one now. You will need to "split" the speaker wires to both the input sides ensuring the polarity is the same. As long as the polarity is the same it doesn't matter whether you have them backwards or not. Then run RCA cables to your amp. Kevin Murray "lollipop" wrote in message oups.com... Does anyone have directions on how to create a mono speaker wire to stereo rca cable. I am trying to hook a mono radio, in a volvo 122s, to a new amplifier. I realize the signal will still be mono, but I would like it to come out on both the left and right speakers of my car. Can I determine which speaker wires are - and +, using a multimeter? Thanks, lollipop |
#4
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On 22 Sep 2005 04:50:35 -0700, "lollipop"
wrote: Does anyone have directions on how to create a mono speaker wire to stereo rca cable. I am trying to hook a mono radio, in a volvo 122s, to a new amplifier. I realize the signal will still be mono, but I would like it to come out on both the left and right speakers of my car. Can I determine which speaker wires are - and +, using a multimeter? Thanks, lollipop Since it's mono, the polarity doesn't really matter. Take the speaker outputs and feed them to both inputs of a line-level converter (connect one speaker wire to both positive inputs on the converter, and connect the other speaker wire to both negative inputs on the converter). Connect the red/white RCA cables to the outputs of the converter, and you should be set. Both RCA cables will have the same signal, and they'll be at a voltage that's appropriate for your EQ or amplifier. -- Scott Gardner "Marge, dont discourage the boy. Weaseling out of things is important to learn. Its what separates us from the animals...except the weasel." (Homer Simpson) |
#5
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I am feeding the speaker level inputs into a clarion EQS744 which has
an aux input with gain control, in this case do I need a LOC? I figured I wouldn't, which is why I asked how I would make the cable to feed into the clarion thanks for the help, lollipop |
#6
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On 22 Sep 2005 07:56:01 -0700, "lollipop"
wrote: I am feeding the speaker level inputs into a clarion EQS744 which has an aux input with gain control, in this case do I need a LOC? I figured I wouldn't, which is why I asked how I would make the cable to feed into the clarion thanks for the help, lollipop Unless your EQ specifically says that it can take speaker-level inputs for the AUX input, you're better off with a converter. The gain control adjustment on the AUX might be adequate if your head unit was only putting out 0.7V or maybe 1 or 2 volts, but it's probably putting out significantly more than that. You can give it a try, though. Turn the gain all the way down and connect the head unit. Put the volume control on the head unit about 3/4 of the way up, and slowly increase the gain on the EQ until the sound level is appropriate. If the sound is loud and distorted even with the EQ gain all the way down, or if you find that you can hardly move the gain adjustment at all without the sound getting too loud and distorting, then you'll know that the voltage from your head unit is too high and that you'll need a converter. -- Scott Gardner "The POP3 server service depends on the SMTP server service, which failed to start because of the following error: The operation completed successfully." (Windows NT Server v3.51) |
#7
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To determine the + and - on a speaker, you can use any 1.5v battery. Using a
larger then 1.5v battery can possibly damage the speaker. put the battery terminals to the speaker terminals, and look at the speaker cone. it will move up or down when the voltage is applied. reverse the battery on the speaker terminals will make the speaker move the opposite direction. when the cone move up, whatever speaker terminal has the + battery lead on it is the speaker + terminal. "lollipop" wrote in message oups.com... Does anyone have directions on how to create a mono speaker wire to stereo rca cable. I am trying to hook a mono radio, in a volvo 122s, to a new amplifier. I realize the signal will still be mono, but I would like it to come out on both the left and right speakers of my car. Can I determine which speaker wires are - and +, using a multimeter? Thanks, lollipop |
#8
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To determine the + and - on a speaker, you can use any 1.5v battery. Using
a larger then 1.5v battery can possibly damage the speaker. Whoa. I've never seen that happen... |
#9
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On Thu, 22 Sep 2005 18:51:28 GMT, MZ wrote:
To determine the + and - on a speaker, you can use any 1.5v battery. Using a larger then 1.5v battery can possibly damage the speaker. Whoa. I've never seen that happen... oh I have. I was foolish enough to do it with a pair of Morel components using a 9v battery. The speakers were just never the same after that... |
#10
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On Thu, 22 Sep 2005 14:51:28 -0400, "MZ"
wrote: To determine the + and - on a speaker, you can use any 1.5v battery. Using a larger then 1.5v battery can possibly damage the speaker. Whoa. I've never seen that happen... I've always used a 9-volt. I wouldn't leave it connected for five minutes or anything, but even that might not hurt it. Alkaline batteries can't really deliver very much current, so they're kind of self-limiting. -- Scott Gardner "I've been accused of vulgarity. I say that's bull****." (Mel Brooks) |
#11
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Whoa. I've never seen that happen...
oh I have. I was foolish enough to do it with a pair of Morel components using a 9v battery. The speakers were just never the same after that... How were they "never the same"? You blew them with a small 9v battery? 9v batteries can't deliver 2+ amps into a 4 ohm speaker load (2A=~9V/4ohms). You'll be doing good to deliver a few watts into the speaker. Typical size alkaline 9v batteries are capable of what? 5w at their ideal load? 4 ohms is most assuredly lower than their output impedance, so their actual output should be significantly less than 5w. |
#12
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On Thu, 22 Sep 2005 22:22:42 GMT, MZ wrote:
How were they "never the same"? You blew them with a small 9v battery? 9v batteries can't deliver 2+ amps into a 4 ohm speaker load (2A=~9V/4ohms). You'll be doing good to deliver a few watts into the speaker. Typical size alkaline 9v batteries are capable of what? 5w at their ideal load? 4 ohms is most assuredly lower than their output impedance, so their actual output should be significantly less than 5w. Well after I did it, the tweeters sounded slightly scratchy and distorted from then on. Maybe it had nothing to do with the battery, but I still refuse to try it again with another speaker... |
#13
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Applying DC to a tweeter is bad news. Not thermally for the voice
coil, but the one way constant excursion can hurt their little surrounds and diaphrams since they are definatly NOT made for a large xmax...LOL |
#14
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Applying DC to a tweeter is bad news. Not thermally for the voice
coil, but the one way constant excursion can hurt their little surrounds and diaphrams since they are definatly NOT made for a large xmax...LOL Hehe yeah, they're certainly not build for excursion. But you get the same kind of transient all the time at turn on. All those systems that get pops with turning off. Or crackling with loose cabling. But they don't usually kill tweeters. The "static" that you get when connecting a tweeter to a 9v source (which is actually less than 9v since the output impedance of a small alkaline battery is nonzero) doesn't have enough power content to send it beyond its xmax. In fact, the back emf (not the motional emf which is often referred to erroneously as back emf) due to the tweeter turning off during normal operation probably gives it the most excursion it'll see. |
#15
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On Thu, 22 Sep 2005 18:22:42 -0400, "MZ"
wrote: Whoa. I've never seen that happen... oh I have. I was foolish enough to do it with a pair of Morel components using a 9v battery. The speakers were just never the same after that... How were they "never the same"? You blew them with a small 9v battery? 9v batteries can't deliver 2+ amps into a 4 ohm speaker load (2A=~9V/4ohms). You'll be doing good to deliver a few watts into the speaker. Typical size alkaline 9v batteries are capable of what? 5w at their ideal load? 4 ohms is most assuredly lower than their output impedance, On this point only: I'm no expert, I eagerly admit, and on this stuff especially I get confused often (which is why I'm asking) but are you saying the impedance of the speakers is actually higher than 4 ohms? If so, isn't that because audio is AC current, but the DC of the battery wouldn't induce any inductive impedance, and with only a battery connected, the impedance would be the same as the resistance, measured with a meter, Yes? Is that likely to be higher than 4 ohms? so their actual output should be significantly less than 5w. Remove NOPSAM to email me. Please let me know if you have posted also. |
#16
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How were they "never the same"? You blew them with a small 9v battery?
9v batteries can't deliver 2+ amps into a 4 ohm speaker load (2A=~9V/4ohms). You'll be doing good to deliver a few watts into the speaker. Typical size alkaline 9v batteries are capable of what? 5w at their ideal load? 4 ohms is most assuredly lower than their output impedance, On this point only: I'm no expert, I eagerly admit, and on this stuff especially I get confused often (which is why I'm asking) but are you saying the impedance of the speakers is actually higher than 4 ohms? If so, isn't that because audio is AC current, but the DC of the battery wouldn't induce any inductive impedance, and with only a battery connected, the impedance would be the same as the resistance, measured with a meter, Yes? Is that likely to be higher than 4 ohms? Sorry, I should have been clearer. What I said was that the output impedance of a typical alkaline 9v battery is higher than 4 ohms. Output impedance refers to the 9v battery's internal resistance. So, since the battery has a nonzero internal resistance, its output voltage is going to drop as you increase the current demands. For example, if you hook your 9v battery up to a small circuit that doesn't draw much current, you'll still measure roughly 9v across the battery terminals. But hook it up to a 4 ohm resistor and the voltage at the battery terminals may only read 5 volts (I'm making up numbers here, but hopefully you get the idea). The initial question was regarding how much power you can deliver to a 4 ohm speaker with a 9v battery. Because of the battery's output impedance, you can't simply say the power is v^2/r, or 81/4 = 20 watts. No way is a 9v battery going to deliver 20 watts. A quick google search seems to indicate that the best you'll do is about 5 watts. There's a law that states that the maximum amount of power that a voltage source with nonzero output impedance can deliver will be delivered to a load that has the same resistance as the output impedance. In other words, if the battery's output impedance is 20 ohms, then you'll deliver the maximum power from the battery if the speaker is 20 ohms. So, although it may seem counterintuitive, you'll actually deliver more power *from a 9v battery* into an 8 ohm tweeter than a 4 ohm tweeter. Oh, and to answer your other question, the resistance of a typical loudspeaker tends to be lower than its nominal impedance. For "4 ohm" speakers, expect the DC resistance to be on the order of 3.2-3.7 ohms when cold. |
#17
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On Fri, 23 Sep 2005 18:22:33 -0400, "MZ"
wrote: How were they "never the same"? You blew them with a small 9v battery? 9v batteries can't deliver 2+ amps into a 4 ohm speaker load (2A=~9V/4ohms). You'll be doing good to deliver a few watts into the speaker. Typical size alkaline 9v batteries are capable of what? 5w at their ideal load? 4 ohms is most assuredly lower than their output impedance, On this point only: I'm no expert, I eagerly admit, and on this stuff especially I get confused often (which is why I'm asking) but are you saying the impedance of the speakers is actually higher than 4 ohms? If so, isn't that because audio is AC current, but the DC of the battery wouldn't induce any inductive impedance, and with only a battery connected, the impedance would be the same as the resistance, measured with a meter, Yes? Is that likely to be higher than 4 ohms? Sorry, I should have been clearer. What I said was that the output impedance of a typical alkaline 9v battery is higher than 4 ohms. Output impedance refers to the 9v battery's internal resistance. So, since the battery has a nonzero internal resistance, its output voltage is going to drop as you increase the current demands. For example, if you hook your 9v battery up to a small circuit that doesn't draw much current, you'll still measure roughly 9v across the battery terminals. But hook it up to a 4 ohm resistor and the voltage at the battery terminals may only read 5 volts (I'm making up numbers here, but hopefully you get the idea). I do. Thanks for explaining all this. The initial question was regarding how much power you can deliver to a 4 ohm speaker with a 9v battery. Because of the battery's output impedance, you can't simply say the power is v^2/r, or 81/4 = 20 watts. No way is a 9v battery going to deliver 20 watts. A quick google search seems to indicate that the best you'll do is about 5 watts. I'll buy that. Even 5 watts sounds like a lot from that little thing, unless there was a 0 ohm short, but I'm willing to believe it could power a 5 watt item. There's a law that states that the maximum amount of power that a voltage source with nonzero output impedance can deliver will be delivered to a load that has the same resistance as the output impedance. I guess I'm not used to the term "output impedance". Yes, looking at the top, that's what I wrote about in the first place. "Internal resistance" is a term I know, but that doesn't mean the other isn't valid. In other words, if the battery's output impedance is 20 ohms, then you'll deliver the maximum power from the battery if the speaker is 20 ohms. So, although it may seem counterintuitive, you'll actually deliver more power *from a 9v battery* into an 8 ohm tweeter than a 4 ohm tweeter. Definitely counterintuitive. Although I think I went throught this with someone regarding lightbulbs. That time I was on your side. Wait, no I wasn't but that's because the situations aren't the same. I said the resistance of a 100 watt lighbubl had to be lower than the resistance of a 60 watt lightbulb. We have the image of the electrons struggling to get thought the wire, because of the reistance, and the more they have to struggle, the more light must be given off. But I don't think that is the way it works. Oh, and to answer your other question, the resistance of a typical loudspeaker tends to be lower than its nominal impedance. For "4 ohm" speakers, expect the DC resistance to be on the order of 3.2-3.7 ohms when cold. Good to know. Of course I could have measured some and found out. Heck, I might have done so a decade or two ago. Who can remember. Here's another question. Chryslers use 8 ohm speakers, but all the replacement speakers sold that I can find are 4 ohms, IIRC, GM used 8 ohm speakers too. Or is Chrysler the only one? If lots of cars use 8 ohm, why are all the replacement speakers 4 ohm? One related question. GM cars had the left channel at the left front and right rear, and the right channel at the other two corners. Do they still do that? and does any other company do that? It makes sense. It may not give the best left-right experience, but since no one in a car sits in the center, especially now when few seats, front or back hold 3 people, most only 2, and even if they hold 3, there is rarely a third person sitting there, and no one sits in the center of the car. So the GM way means that everyone gets equal volumes of left and right, even though they are mixed together. The Chrysler system, straight left and right, means that if the driver turns up the right channel since he is sitting farther from those speakers, he's ok unless he carries a passenger. Then if he makes them equal, neither person here's a balanced left-right sound. No? Remove NOPSAM to email me. Please let me know if you have posted also. |
#18
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In other words, if
the battery's output impedance is 20 ohms, then you'll deliver the maximum power from the battery if the speaker is 20 ohms. So, although it may seem counterintuitive, you'll actually deliver more power *from a 9v battery* into an 8 ohm tweeter than a 4 ohm tweeter. Definitely counterintuitive. Although I think I went throught this with someone regarding lightbulbs. That time I was on your side. Wait, no I wasn't but that's because the situations aren't the same. I said the resistance of a 100 watt lighbubl had to be lower than the resistance of a 60 watt lightbulb. We have the image of the electrons struggling to get thought the wire, because of the reistance, and the more they have to struggle, the more light must be given off. But I don't think that is the way it works. Yes, the resistance of the 100w bulb is lower than the 60w bulb. Power = Voltage squared divided by resistance; since voltage remains constant in both cases, the only way to increase power would be to decrease resistance. Anyway, think of it this way. We know that the current will be greatest when you short the output. But we also know that the voltage at the output terminals decreases to near zero in that situation. Since power equals voltage times current, then you want to find the resistance of the load that will give you the right balance of current and voltage so that V x I is greatest. It can be shown mathematically that this ideal resistance is equal to the output impedance, or internal resistance, of the voltage source. Here's another question. Chryslers use 8 ohm speakers, but all the replacement speakers sold that I can find are 4 ohms, IIRC, GM used 8 ohm speakers too. Or is Chrysler the only one? If lots of cars use 8 ohm, why are all the replacement speakers 4 ohm? Most cars that don't have "premium" sound systems (which are becomign fewer these days) use 4 ohm speakers. And most aftermarket head units are designed to drive 4 ohm speakers. So that's why you mostly find 4 ohm speakers out there. There are 8 ohm speakers also, but they're a bit harder to find. It's also easy to find 8 ohm raw drivers, but those would require a separate woofer and tweeter, which may be more than what you're willing to do. One related question. GM cars had the left channel at the left front and right rear, and the right channel at the other two corners. Do they still do that? and does any other company do that? Nope. |
#19
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On Sun, 25 Sep 2005 18:09:37 GMT, MZ wrote:
IIRC, GM used 8 ohm speakers too. Or is Chrysler the only one? If lots of cars use 8 ohm, why are all the replacement speakers 4 ohm? Most cars that don't have "premium" sound systems (which are becomign fewer these days) use 4 ohm speakers. And most aftermarket head units are designed to drive 4 ohm speakers. So that's why you mostly find 4 ohm speakers out there. There are 8 ohm speakers also, but they're a bit harder to find. It's also easy to find 8 ohm raw drivers, but those would require a separate woofer and tweeter, which may be more than what you're willing to do. Well I found a junk yard car with dash speakers. Most don't have them, but this one had had an Infinity radio.. So for 5 dollars a piece, I have a pair, and my ear is not so great that I need anything better.. It also had coaxial speakers in the rear, and I got those too. They have connectors for four wires, each. S since I don't have the Infinity amplifier, which they are meant for, I'll have to figure out how to connect the tweeter to the bigger speaker. One related question. GM cars had the left channel at the left front and right rear, and the right channel at the other two corners. Do they still do that? and does any other company do that? Nope. Nope to which qustions? Remove NOPSAM to email me. Please let me know if you have posted also. |
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