Microphone cable for RCA interconnect

[Denis29]

I need to make a cable which has 1/4" Mono jack on one side and RCA on the other. I ordered a nice budget cable, for $0.45/ft, but it is a microphone cable, with 2 wires under a copper braid insulation.

I read that the braiding is connected to ground on both sides. But the second signal wire, which isn't "used" - does it get connected to ground on one end, or what's the best way to handle it?

 

[j_garcia]

They sell 1/4 to RCA adapters for $4 at www.partsexpress.com

 

[Denis29]

They sell 1/4 to RCA adapters for $4 at www.partsexpress.com

This is where I'm getting the cable, and I'm aware of adapters. I went on recommendation to reduce the number of connections by using proper cable without adapters.

So my question stands.

 

[bandphan]

This is where I'm getting the cable, and I'm aware of adapters. I went on recommendation to reduce the number of connections by using proper cable without adapters.

So my question stands.

Who said that you got the proper cable.

 

[Denis29]

Who said that you got the proper cable.

Do I have to be a lawyer to word my question?

I'm not looking to get into a cable fight, I just want to know how to handle the 2nd signal wire properly given that this is the cable I'm working with.

 

[TLS Guy]

I need to make a cable which has 1/4" Mono jack on one side and RCA on the other. I ordered a nice budget cable, for $0.45/ft, but it is a microphone cable, with 2 wires under a copper braid insulation.

I read that the braiding is connected to ground on both sides. But the second signal wire, which isn't "used" - does it get connected to ground on one end, or what's the best way to handle it?

Just connect each end of either the blue or white cable to the screen and solder both screen and the wire you select to the ground of both the 1/4' and the RCA and you will be fine. Obviously the wire you do not ground goes hot to hot.

You will be just fine.

 

[Denis29]

Just connect each end of either the blue or white cable to the screen and solder both screen and the wire you select to the ground of both the 1/4' and the RCA and you will be fine. Obviously the wire you do not ground goes hot to hot.

You will be just fine.

I thought about doing that but was wondering if this hook-up might inject what some articles call ground-loop noise. Can't trust everything you read, but I like to make sure...

I'll go ahead and wire it as you say.

 

[TLS Guy]

I thought about doing that but was wondering if this hook-up might inject what some articles call ground-loop noise. Can't trust everything you read, but I like to make sure...

I'll go ahead and wire it as you say.

Anyone who told you that is talking out the wrong end. How could it aggravate a ground loop? That method results in the least resistance between grounds. Ground loops occur with increased frequency as you increase resistance between grounds.

 

[Denis29]

Anyone who told you that is talking out the wrong end. How could it aggravate a ground loop? That method results in the least resistance between grounds. Ground loops occur with increased frequency as you increase resistance between grounds.

I didn't think it made a whole lot of sense either.

I kind of have a tight budget to work with, so I can't afford Blue Jeans or Kimber Kable... For the future, what's an example of a good bulk cable to make RCA interconnects that combines quality and value? Are microphone, instrument, and coax cables all suitable choices for RCA interconnects?

 

[TLS Guy]

I didn't think it made a whole lot of sense either.

I kind of have a tight budget to work with, so I can't afford Blue Jeans or Kimber Kable... For the future, what's an example of a good bulk cable to make RCA interconnects that combines quality and value? Are microphone, instrument, and coax cables all suitable choices for RCA interconnects?

I have a lot of spare cables, I reuse and adapt. You can get a large Belden drum, but that will cost you. The cheapest solution is to buy Radio Shack 25 ft audio cables, and split them and terminate them any way you want.

You can by good connectors in bulk at a good price from Mouser.

 

[highfigh]

I didn't think it made a whole lot of sense either.

I kind of have a tight budget to work with, so I can't afford Blue Jeans or Kimber Kable... For the future, what's an example of a good bulk cable to make RCA interconnects that combines quality and value? Are microphone, instrument, and coax cables all suitable choices for RCA interconnects?

A lot of instrument cable isn't made for wide bandwidth and some are actually marketed as being best for bass or guitar. Guess who is one of those brands. Two syllables and they like to sue people.

They will all carry the signal but using what is called 'audio cable' is easiest. The kind you bought will definitely work, though. Just do what TLS recommended. USe the kind that has tinned or bare copper wire and shield.

 

[Denis29]

They will all carry the signal but using what is called 'audio cable' is easiest.

That's what I was looking for. Monoprice is down right now. PartsExpress had the following categories for bulk cable:

Automotive Power Wire
CAT 5 / 6 Network Wire
Coaxial Cable
Flat Speaker Wire
Guitar / Instrument Wire
Hook-Up Wire
In-Wall Speaker Wire
IR Wire
Microphone / Signal Wire
Plenum Speaker Wire
Power Wire
Pro Sound Speaker Wire
Red / Black Zip Cord
S-Video Wire
Snake Wire
Speaker Wire
Telephone Wire
Underground Wire

So I figured I have a choice between Coax, Microphone/Signal wire, and Guitar/Instrument wire (which has one conductor and a shield). I figured they'd have general-purpose audio cable category, but they didn't. I just went with the one that is sold per foot (small application right now) at a best price and best reviews

 

[Denis29]

In principle, all RCA cables are either coaxial or twisted pair, right? So what are the differences, if any, between RCA cables that carry analog signal and RCA cables that carry digital signal? Aren't they one and the same, with the only difference that the cables for digital signal require heftier shielding?

 

[highfigh]

In principle, all RCA cables are either coaxial or twisted pair, right? So what are the differences, if any, between RCA cables that carry analog signal and RCA cables that carry digital signal? Aren't they one and the same, with the only difference that the cables for digital signal require heftier shielding?

Coaxial cable is easier to terminate when soldering most connectors used with unbalanced signal. The third conductor in mic cable is for balanced signal with XLR plugs but it works fine with RCA plugs, although it's less bulky if you clip one wire off at each end. Digital and audio cables are generally interchangeable, to a certain point. If you can find flexible RG-59, I would use that with compression ends. If you absolutely need 1/4" at one end, make sure the cable has tinned or solid copper shield and center conductor. If you want the most flexible cable, get RG-58 if you can find it- with that, the center conductor is stranded. Coax is usually sweep tested and the better ones are able to go to 3GHz.

 

[Denis29]

I am shopping for bulk cable now and making my own interconnects.

I loved the microphone cable I posted about here for my RCA-to-1/4' interconnects - very nice shielding and *great* flexibility. I am very tempted to use it for RCA-to-RCA interconnects, but I guess I should go coax here, and it would be cheaper to do so as well...

Here's a cable I'm looking at right now:

Dayton 3106ADOA RG-6/U Solid Copper 95% Cu Braid
http://www.parts-express.com/pe/pshowdetl.cfm?&DID=7&Partnumber=101-101&ctab=2#Tabs

Center conductor: 18AWG solid copper
Dielectric: 4.57 mm dia. foamed PE
Shield: 125% coverage aluminized Mylar foil and 95% coverage copper braid
Nominal impedance: 75 ohms
Velocity of propagation: 82%
Capacitance: 53.1 pF/meter
Nominal attenuation: 21.6 dB/100 meters @ 1 GHz
Overall diameter: 6.86 mm.

Good choice? Is this cable going to be very stiff? Otherwise, it looks like a very nice audio cable, and $0.25/ft to boot!

 

[highfigh]

I am shopping for bulk cable now and making my own interconnects.

I loved the microphone cable I posted about here for my RCA-to-1/4' interconnects - very nice shielding and *great* flexibility. I am very tempted to use it for RCA-to-RCA interconnects, but I guess I should go coax here, and it would be cheaper to do so as well...

Here's a cable I'm looking at right now:

Dayton 3106ADOA RG-6/U Solid Copper 95% Cu Braid
http://www.parts-express.com/pe/pshowdetl.cfm?&DID=7&Partnumber=101-101&ctab=2#Tabs

Center conductor: 18AWG solid copper
Dielectric: 4.57 mm dia. foamed PE
Shield: 125% coverage aluminized Mylar foil and 95% coverage copper braid
Nominal impedance: 75 ohms
Velocity of propagation: 82%
Capacitance: 53.1 pF/meter
Nominal attenuation: 21.6 dB/100 meters @ 1 GHz
Overall diameter: 6.86 mm.

Good choice? Is this cable going to be very stiff? Otherwise, it looks like a very nice audio cable, and $0.25/ft to boot!

Never used it, so I have no idea of how stiff it is. If you still have the cable in your original post, there's no reason to not use it.

How much of this will you need? In-wall cable is more stuff than cable made for other applications. RG59 works great and with a compression tool, you'll be able to work with RCA, BNC and F compression connectors. You can even find dual-RG59 cable but get the kind with solid copper center wire.

Mic cable with soldered ends works great and may cost less but the danger of bad solder joints exists. I used Planet Waves cable on a job and it worked really well. It's easy to work with, the ends can be re-used and don't clamp on as tightly as some of the compression or ready-made cables I have used.

 

[Denis29]

Never used it, so I have no idea of how stiff it is. If you still have the cable in your original post, there's no reason to not use it.

How much of this will you need? In-wall cable is more stuff than cable made for other applications. RG59 works great and with a compression tool, you'll be able to work with RCA, BNC and F compression connectors. You can even find dual-RG59 cable but get the kind with solid copper center wire.

Mic cable with soldered ends works great and may cost less but the danger of bad solder joints exists. I used Planet Waves cable on a job and it worked really well. It's easy to work with, the ends can be re-used and don't clamp on as tightly as some of the compression or ready-made cables I have used.

I don't have any more of the mic cable I bought - I only bought enough for that particular application...

The only problem with that RG-6 cable I posted above is that the cable OD is 6.9 mm, and most RCA plugs accept up to 6 mm OD. So I would be forced to get the plugs with 8.3-mm cable inlet, and I would rather not do that. The choices are slimmer, and plugs are more expensive. Adds up when you may need 12-16 of these things!

I soldered the mic cable I originally posted above, and that worked out great. I'm pretty good at soldering, and I kind of favor soldered over crimped. Maybe I'm wrong - I don't know.

The RG-59 cables on PartsExpress all have copper-clad steel center conductor. I would rather go all Cu, but PartsExpress only has those in RG-6, like the one I posted.

PS. I forgot to add that this is for a player-receiver-subwoofer hook-up, so each cable will probably be between 2 and 6 ft long.

 

[Denis29]

Oh, I overlooked this one: PartsExpress do carry RG-58/U, which has 20 AWG stranded copper center, PE foam, and Cu braiding that provides 72% shielding. 52 Ohm impedance. Capacitance 22 (guessing pF/m ??)

Would this a nice interconnect cable? That microphone cable I used has 95% shielding from copper braid... I don't know how much that matters.

The RG-58/U is about $0.19/ft. Microphone cable I used is about $0.40/ft. I don't mind paying for the mic cable if that's the better alternative of these two.

 

[highfigh]

I don't have any more of the mic cable I bought - I only bought enough for that particular application...

The only problem with that RG-6 cable I posted above is that the cable OD is 6.9 mm, and most RCA plugs accept up to 6 mm OD. So I would be forced to get the plugs with 8.3-mm cable inlet, and I would rather not do that. The choices are slimmer, and plugs are more expensive. Adds up when you may need 12-16 of these things!

I soldered the mic cable I originally posted above, and that worked out great. I'm pretty good at soldering, and I kind of favor soldered over crimped. Maybe I'm wrong - I don't know.

The RG-59 cables on PartsExpress all have copper-clad steel center conductor. I would rather go all Cu, but PartsExpress only has those in RG-6, like the one I posted.

PS. I forgot to add that this is for a player-receiver-subwoofer hook-up, so each cable will probably be between 2 and 6 ft long.

F-Conn, Ideal, Monster and most other brands sell RCA compression plugs for RG6. The tough one is RG6 Quad shield. Don't get the copper clad unless you can guarantee no tight bends. Bending stiff cables means the center conductor will compress the dielectric and that not only reduces bandwidth (when used for RF) but it also makes noise problems more likely because the distance from the center conductor to the shield makes a difference.

If PE doesn't have solid copper cable, go someplace else. The ends will still work.

 

[highfigh]

Oh, I overlooked this one: PartsExpress do carry RG-58/U, which has 20 AWG stranded copper center, PE foam, and Cu braiding that provides 72% shielding. 52 Ohm impedance. Capacitance 22 (guessing pF/m ??)

Would this a nice interconnect cable? That microphone cable I used has 95% shielding from copper braid... I don't know how much that matters.

The RG-58/U is about $0.19/ft. Microphone cable I used is about $0.40/ft. I don't mind paying for the mic cable if that's the better alternative of these two.

You don't want RG58 unless you plan to solder the ends. For that use, it would be fine. RG58 is generally used with BNC plugs and all of the other types want a stiff stinger for insertion into the tip. RG58 was originally used for high frequency signals and when computer networking began, they had what's called a 'ring network', which had a cable going from one computer to the next, in a circle.

Technically, RG6, RG59 and RG58 are different. RG58 is considered 50 Ohm and the others are 75 Ohm.