TexDrone Posted June 7, 2022 Share Posted June 7, 2022 Can 7C 14ga multiconductor cable be used to carry audio signal from three separate amplifiers (high - mid - low) to their respective speaker drivers? Would this type of cable need to be shielded or twisted in some certain way? I would like to build custom cable assemblies to run from my amps to each of my LaScalas. Thanks Quote Link to comment Share on other sites More sharing options...
Edgar Posted June 8, 2022 Share Posted June 8, 2022 If "7C" means seven conductor, then you can think of it as three pairs plus one extra. Just don't be tempted to connect all of the negative wires together -- some amps will tolerate this, but many will not. Ideally you would use three twisted pairs, because without the twists there can be crosstalk between the signal pairs due to their close proximity. Maybe experiment to see if it's objectionable -- I suspect that, with such small signals and short distances, it won't be. Quote Link to comment Share on other sites More sharing options...
TexDrone Posted June 8, 2022 Author Share Posted June 8, 2022 19 hours ago, Edgar said: If "7C" means seven conductor, then you can think of it as three pairs plus one extra. Just don't be tempted to connect all of the negative wires together -- some amps will tolerate this, but many will not. Go to topic listing Ideally you would use three twisted pairs, because without the twists there can be crosstalk between the signal pairs due to their close proximity. Maybe experiment to see if it's objectionable -- I suspect that, with such small signals and short distances, it won't be. Correct. Attached is the cut sheet for the cable I have on hand. (Part# CF130US-25-07) It is technically a flexible machine control cable. My plan is to use 2 conductors per 'channel' (not sure if that is correct technical term). Right now I have three pairs of speaker cable running between each amp and speaker cabinet. This will let me clean up the cable clutter by having them wrapped in one cable jacket... but I am unclear if the signals will interfere with one another. Your advice is very much appreciated! I will try building one assembly and see how it sounds. CF130US-25-07.pdf Quote Link to comment Share on other sites More sharing options...
LTusler Posted June 8, 2022 Share Posted June 8, 2022 Which gauge cable do you have and how long will the runs be to the speakers? Quote Link to comment Share on other sites More sharing options...
Khornukopia Posted June 8, 2022 Share Posted June 8, 2022 21 hours ago, TexDrone said: Can 7C 14ga multiconductor cable be used to carry audio signal from three separate amplifiers (high - mid - low) to their respective speaker drivers? Would this type of cable need to be shielded or twisted in some certain way? I would try it. "Concentrically layered" may not be as ideal as twisted pairs, but speaker wire current is usually very low, so it might not cause an audible concern. One thing I don't like (on the data sheet) is the six of the conductors having the same black color insulation. Just make sure to label both ends very well and double check all your connections. 😄 Quote Link to comment Share on other sites More sharing options...
Marvel Posted June 8, 2022 Share Posted June 8, 2022 I wouldn't try very long runs, but 14 gauge should be ok Quote Link to comment Share on other sites More sharing options...
Edgar Posted June 8, 2022 Share Posted June 8, 2022 I would keep the woofer wires as physically distant from the midrange and tweeter wires as the construction permits. Woofers carry the most current, often by a considerable amount. Quote Link to comment Share on other sites More sharing options...
Racer X Posted June 8, 2022 Share Posted June 8, 2022 1 hour ago, TexDrone said: in one cable jacket... but I am unclear if the signals will interfere with one another Interesting looking wire, but this may be a concern. I once had multiple runs of speaker wire tightly bundled, but noticed improvement when I spaced them out. Interested to hear your findings.... Quote Link to comment Share on other sites More sharing options...
TexDrone Posted June 8, 2022 Author Share Posted June 8, 2022 2 hours ago, LTusler said: Which gauge cable do you have and how long will the runs be to the speakers? 14ga cable and the runs are 6' and 12' Quote Link to comment Share on other sites More sharing options...
TexDrone Posted June 8, 2022 Author Share Posted June 8, 2022 40 minutes ago, Racer X said: Interesting looking wire, but this may be a concern. I once had multiple runs of speaker wire tightly bundled, but noticed improvement when I spaced them out. Interested to hear your findings.... The wire is left over from a CNC machine build. Quote Link to comment Share on other sites More sharing options...
TexDrone Posted June 8, 2022 Author Share Posted June 8, 2022 1 hour ago, Khornukopia said: I would try it. "Concentrically layered" may not be as ideal as twisted pairs, but speaker wire current is usually very low, so it might not cause an audible concern. One thing I don't like (on the data sheet) is the six of the conductors having the same black color insulation. Just make sure to label both ends very well and double check all your connections. 😄 The wires are labeled very well for easy identification. Quote Link to comment Share on other sites More sharing options...
Edgar Posted June 8, 2022 Share Posted June 8, 2022 8 minutes ago, TexDrone said: The wire is left over from a CNC machine build. I certainly hope that this doesn't lead to another Audiophile Myth. 🙂 Using non-audio wires for audio? Blasphemy! 2 Quote Link to comment Share on other sites More sharing options...
Khornukopia Posted June 9, 2022 Share Posted June 9, 2022 2 hours ago, Khornukopia said: I would try it... Maybe I will change my thoughts about this, because ... 1 hour ago, Edgar said: I would keep the woofer wires as physically distant from the midrange and tweeter wires as the construction permits. Woofers carry the most current, often by a considerable amount. 1 hour ago, Racer X said: Interesting looking wire, but this may be a concern. I once had multiple runs of speaker wire tightly bundled, but noticed improvement when I spaced them out. Interested to hear your findings.... You guys persuaded me to bring out my Fluke voltmeter, connect it onto the 2 unused conductors of a 4 conductor "speaker wire" while powering a loudspeaker with the other 2 conductors. The inductance is generating a small voltage in the 2 unused wires. This was a quick non-scientific observation so there could be some error but, I think it will steer me to study the situation with all my speaker wires. 1 1 Quote Link to comment Share on other sites More sharing options...
babadono Posted June 9, 2022 Share Posted June 9, 2022 4 minutes ago, Khornukopia said: The inductance is generating a small voltage in the 2 unused wires. This was a quick non-scientific observation so there could be some error but, I think it will steer me to study the situation with all my speaker wires Put an 8 ohm load on the unused pair at one end simulating a speaker load and lets say a tenth of an ohm at the other simulating the output impedance of an amplifier. What does the meter read now? 1 Quote Link to comment Share on other sites More sharing options...
Edgar Posted June 9, 2022 Share Posted June 9, 2022 4 minutes ago, Khornukopia said: You guys persuaded me to bring out my Fluke voltmeter, connect it onto the 2 unused conductors of a 4 conductor "speaker wire" while powering a loudspeaker with the other 2 conductors. The inductance is generating a small voltage in the 2 unused wires. This was a quick non-scientific observation so there could be some error but, I think it will steer me to study the situation with all my speaker wires. Were the two unused wires connected to loads? The induced voltage is likely to be higher with an open circuit than with terminations. Try it with a few Ohms on one end (loudspeaker proxy) and a few milliOhms on the other (amplifier proxy). Last time I triamplified my speakers, I braided the cables. That way each one crosses the others at an angle, reducing mutual coupling. 1 1 Quote Link to comment Share on other sites More sharing options...
babadono Posted June 9, 2022 Share Posted June 9, 2022 IOW I think @TexDrone is going to be just fine. 6 or 12 feet? Pffffttt. Quote Link to comment Share on other sites More sharing options...
Edgar Posted June 9, 2022 Share Posted June 9, 2022 @babadono, great minds think alike. Quote Link to comment Share on other sites More sharing options...
Racer X Posted June 9, 2022 Share Posted June 9, 2022 https://en.wikipedia.org/wiki/Proximity_effect_(electromagnetism) Quote Link to comment Share on other sites More sharing options...
Khornukopia Posted June 9, 2022 Share Posted June 9, 2022 5 minutes ago, babadono said: Put an 8 ohm load on the unused pair at one end simulating a speaker load and lets say a tenth of an ohm at the other simulating the output impedance of an amplifier. What does the meter read now? 4 minutes ago, Edgar said: Were the two unused wires connected to loads? The induced voltage is likely to be higher with an open circuit than with terminations. Try it with a few Ohms on one end (loudspeaker proxy) and a few milliOhms on the other (amplifier proxy). Last time I triamplified my speakers, I braided the cables. That way each one crosses the others at an angle, reducing mutual coupling. 3 minutes ago, babadono said: IOW I think @TexDrone is going to be just fine. 6 or 12 feet? Pffffttt. I feel better already from reading your replies. The wires I measured were open ended. Re-testing with resistors will be later but at least I can stop being overly concerned about all my 4 conductor wire runs. Quote Link to comment Share on other sites More sharing options...
Khornukopia Posted June 9, 2022 Share Posted June 9, 2022 (edited) I could only find an 8 ohm resistor for now. Just connecting that across the open wires and watching the voltmeter saved me from ordering different and expensive speaker wires for my audio systems. EDIT; I retested with a proper load on the wires, as suggested above, and noted 0.000 volts, so there isn't a problem. Edited June 12, 2022 by Khornukopia update results Quote Link to comment Share on other sites More sharing options...
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