RCA Audio Cables

[gregski]

Possibly a few stupid questions: If the ZLD is single ended what type of RCA's are included in their kits? Because they only sell the V8 series which is twisted pair.

Since I will be starting my stereo install soon, how do you determine if your amps are differential or single ended? I will be doing Wetsounds, but I do not see that info.

Not stupid questions at all. The problem is the confusion that the industry intentionally creates to upsell expensive products.

All consumer level audio equipment like car stereos use single ended signals. The outputs from the stereo and the inputs to an amp are all single ended.. They use RCA connectors and a coax cable offers the best noise immunity. Differential audio signals usually use XLR connectors (link) You'll probably recognize these more as professional stage and studio equipment.

So pretty much if you see RCA connectors, the drivers/receivers are single ended.

For those cables you mention, the manufacturer is Metra and frankly, they appear to be using very liberal "marketing". Here is a link to their catalog: http://www.metraonline.com/files/cat...EC_CATALOG.pdf

The only cables that appear to be twisted pair are the V12 series but the weird part is that they actually look to have three conductor wires which doesn't even make sense. What does the third wire connect to? In the real world of signal transmission, there is shielded twisted pair, which is like a twisted pair but with a ground shield sort of like a coax but then you have 3 connections +/-/GND on each and all 3 conductors are certainly not braided like this.

It looks to me like they braided 3 wires because it looks fancy but it would only be for looks. Unless I'm missing something I would say that those V12s are pure gimmikry.

The V10s are "dual twist" but I have no idea what that really means. They appear to be a coax... which they should be. Some of their other selling features are "high tolerance compact machined metal end" and "Packaged in High-End Retail Box". Plenty of marketing here. They also list "Ultra-flexible PVC blended jacket" which is a good feature if you need it, such as tight installations. The V8s aren't in that catalog but they are also "dual twist" which again is unclear what it actually means.

The V6s look like fine RCAs to me, without the extra cost for the "high-end retail box".

[jstenger]

That's true if the drivers/receivers are differential. If they are single ended (which the ZLD is) then a coax RCA is the right cable.

I believe the ZLDMKII is a differential also. The inputs and outputs are insulated from the frame. I need to still do a continuity test to verify.

[jstenger]

All consumer level audio equipment like car stereos use single ended signals. The outputs from the stereo and the inputs to an amp are all single ended.. They use RCA connectors and a coax cable offers the best noise immunity. Differential audio signals usually use XLR connectors (link) You'll probably recognize these more as professional stage and studio equipment.

So pretty much if you see RCA connectors, the drivers/receivers are single ended.

I disagree as far as the Exile XM amps go. From what I have read, and testing I have done, the XM's are differential amps. Neither the center conductor nor the outer conductor are connected to the chassis or the power leads.

[David Analog]

No amplifier has the center conductor connected to chassis.
You will find almost NO amplifiers that have the input RCA shield DC connected to the chassis or the power supply ground. The shield ground is floating, in other words, perhaps 10kOhm above ground. But you are only measuring an AC circuit with DC. In any case, a floating input ground in no way indicates that the input section is balanced differential.

[gregski]

In any case, a floating input ground in no way indicates that the input section is balanced differential.

Exactly.

And it's worth pointing out that basically all amplifiers use differential op-amps so the manufacture may well state that they use differential amplifiers but in no way does this mean that the in/out signals are balanced differential signals. Restated: you use differential op-amps for single-ended signals.

Even if an amplifier used a differential input, the source output is single ended, so you'd still want to use a coax cable and drive it single-ended.

[jstenger]

Exactly.

And it's worth pointing out that basically all amplifiers use differential op-amps so the manufacture may well state that they use differential amplifiers but in no way does this mean that the in/out signals are balanced differential signals. Restated: you use differential op-amps for single-ended signals.

Even if an amplifier used a differential input, the source output is single ended, so you'd still want to use a coax cable and drive it single-ended.

What do you mean by differential op-amp?

[David Analog]

op-amp. operation amp. Integrated circuit. IC chip. Performs a designated function ending in a transistor (a low level processor and amplifier). Tiny as opposed to a bunch a space-consuming discrete components.
Some are linear amplifiers such as the chips that drive the HU or EQ preamp outputs. Some are for active crossover functions. Some are for EQ tone functions. Some are used at the amplifier inputs. The applications go on and on.

[mbusch5]

Not stupid questions at all. The problem is the confusion that the industry intentionally creates to upsell expensive products.

All consumer level audio equipment like car stereos use single ended signals. The outputs from the stereo and the inputs to an amp are all single ended.. They use RCA connectors and a coax cable offers the best noise immunity. Differential audio signals usually use XLR connectors (link) You'll probably recognize these more as professional stage and studio equipment.

So pretty much if you see RCA connectors, the drivers/receivers are single ended.

For those cables you mention, the manufacturer is Metra and frankly, they appear to be using very liberal "marketing". Here is a link to their catalog: http://www.metraonline.com/files/cat...EC_CATALOG.pdf

The only cables that appear to be twisted pair are the V12 series but the weird part is that they actually look to have three conductor wires which doesn't even make sense. What does the third wire connect to? In the real world of signal transmission, there is shielded twisted pair, which is like a twisted pair but with a ground shield sort of like a coax but then you have 3 connections +/-/GND on each and all 3 conductors are certainly not braided like this.

It looks to me like they braided 3 wires because it looks fancy but it would only be for looks. Unless I'm missing something I would say that those V12s are pure gimmikry.

The V10s are "dual twist" but I have no idea what that really means. They appear to be a coax... which they should be. Some of their other selling features are "high tolerance compact machined metal end" and "Packaged in High-End Retail Box". Plenty of marketing here. They also list "Ultra-flexible PVC blended jacket" which is a good feature if you need it, such as tight installations. The V8s aren't in that catalog but they are also "dual twist" which again is unclear what it actually means.

The V6s look like fine RCAs to me, without the extra cost for the "high-end retail box".

Thanks for the info, definitley shed some light. In an attempt to make it easy, basically using an "RCA" cable will work on everyday amps and stereo equipment weather its "dual twist" or "woven coax"? I noticed Wetsounds says "quad twist" so I'm sure its all gimmick.

[sandm]

both boats and some of my home audio from here:
http://www.knukonceptz.com/

never ordered their "high end" stuff, stuck mostly to mid-price and seems to perform good.

[gregski]

Thanks for the info, definitley shed some light. In an attempt to make it easy, basically using an "RCA" cable will work on everyday amps and stereo equipment weather its "dual twist" or "woven coax"? I noticed Wetsounds says "quad twist" so I'm sure its all gimmick.

Yes, a coax cable is the best choice for basically everything you'll find at home or in your car - anything with RCA connectors. And yes, I believe that "dual twist" is just a marketing word. Those cables certainly look like coax.