Those who own Audioquest cable...what do you think?

[plissken]

But isn't the signal path much simpler with SE connections?

 

R

 

The signal path is generally half the components. I don't know about simpler. Just less parts heavy.

[plissken]

Then obviously you don't have a signal chain that benefits from having continuity of the 0 volts (earth) connection from Power Amplifier, through the Preamplifier, then extended to the source component which can result in very low S/N if the design of the actual components is first rate.

 

I don't need to read your RANE engineering notes. My reply was in response to this statement from you .

 

 

And again I will state: How do you know what my setup is? I have a total of one SE cable. That is my Home Theater (I have dedicated 2.0) sub woofer.

 

Goes from my AVR to a Art Clean Box Pro (active isolation transformer) to a Crown XTi 4002 to four 12" subs.

[sandyk]

SE connections work and they can work well. They are not optimal technically speaking.

Balanced circuitry is not necessarily an advantage in typical consumer applications where short leads are used, and SE connections can often outperform them in this case, without increasing the source impedance, S/N, or the added cost of component duplication , improved PSUs to power 2 individual sections etc.

[plissken]

Then obviously you don't have a signal chain that benefits from having continuity of the 0 volts (earth) connection from Power Amplifier, through the Preamplifier, then extended to the source component which can result in very low S/N if the design of the actual components is first rate.

 

I don't need to read your RANE engineering notes. My reply was in response to this statement from you .

 

Balanced circuitry is not necessarily an advantage in typical consumer applications where short leads are used, and SE connections can often outperform them in this case, without increasing the source impedance, S/N, or the added cost of component duplication , improved PSUs to power 2 individual sections etc.

 

A fully differential setup can have up to 6dB better noise floor vs single ended. So there is that going for it.

 

SE can most certainly be stellar.

[Jud]

A fully differential setup can have up to 6dB better noise floor vs single ended. So there is that going for it.

 

SE can most certainly be stellar.

 

So the better noise floor would be possible even if the balanced and SE cables had the same LCR, yes?

[Jud]

They should be nill because the sensitive parts should be in an rf cage/oven.

 

I assume the RF cage would not keep out noise coming through the inputs, though, thus the usefulness of things like shielding and balanced cables.

[sandyk]

A fully differential setup can have up to 6dB better noise floor vs single ended. So there is that going for it.

 

SE can most certainly be stellar.

 

Unless there is added attention paid to the PSU area the results may very well be worse. Add to that the difficult task, due to component tolerances of getting absolutely identical outputs from both halves.

[gmgraves]

Zero.

 

Correct, and for all practical purposes, Interconnects are there now. At less than about 3 meters of length, the LRC of most interconnect cables are so low that it is difficult to measure the attenuation across the audio passband, let alone hear it. No, if there is a real difference between interconnect cables sound (and I'm not saying that there isn't), LRC of the cable itself is not the cause of it.

[jabbr]

In my experience it is mostly differences in types of shielding (more or less and different patterns) as well as connectors -- something to be said for solid high quality connectors though they don't need to be expensive.

[gmgraves]

There can be a lot of data available:

 

Belden RG6 (1694a):

 

Nom. Characteristic Impedance:

Impedance (Ohm)

75

 

Nom. Inductance:

Inductance (μH/ft)

0.106

 

Nom. Capacitance Conductor to Shield:

Capacitance (pF/ft)

16.2

 

Nominal Velocity of Propagation:

VP (%)

82

 

Nominal Delay:

Delay (ns/ft)

1.24

 

Nom. Conductor DC Resistance:

DCR @ 20°C (Ohm/1000 ft)

6.4

 

Nominal Outer Shield DC Resistance:

DCR @ 20°C (Ohm/1000 ft)

2.8

 

Nom. Attenuation:

Freq. (MHz) Attenuation (dB/100 ft.)

1.000 0.240

3.580 0.440

5.000 0.520

6.000 0.570

7.000 0.610

10.000 0.710

12.000 0.780

25.000 1.080

67.500 1.650

71.500 1.690

88.500 1.860

100.000 1.950

135.000 2.240

143.000 2.300

180.000 2.570

270.000 3.170

360.000 3.690

540.000 4.600

720.000 5.380

750.000 5.500

1000.000 6.420

1500.000 7.990

2000.000 9.370

2250.000 10.010

3000.000 11.780

4500.000 14.920

 

Max. Operating Voltage - UL:

Voltage

300 V RMS

 

Start Freq. (MHz) Stop Freq. (MHz) Min. RL (dB)

5.000 1600.000 23.000

1600.000 4500.000 21.000

 

Sweep Test

Sweep Testing: 100% Sweep tested 5 MHz to 4.5 GHz.

 

Look at what you quoted! Less than a quarter of a dB of attenuation at 1 MEGAHERTZ for 100 FEET of cable length. They don't even spec loss at at 20 KHz, because it's entirely negligible!

[gmgraves]

Except:

 

1. People do hear differences in cables, often repeatable.

2. They are not hearing imaginary differences.

3. What is causing the difference?

 

We know what it is not - it is not massive differences in LCR. It is also, not imagination.

 

Conundrum - which always means one thing. There is some factor there we are missing.

 

-Paul

 

Many of us in this discussion are not saying that people aren't hearing differences in cables. What *I* am saying (along with a couple of others) is simply that those differences are not and cannot be related to LRC measurements because those figures are minuscule and the results negligible. When a 100 ft long piece of coax only attenuates a ONE MHz signal by less than 1/4 of a dB, then 3 ft of said cable is going to attenuate a 20KHz signal, essentially not at all! If Interconnects do sound different, then the reason why they sound different must lie elsewhere.

 

Mission statement: I'm in this conversation because the subject interests me and it is an area in which I have some personal expertise. I was an aerospace cabling engineer for several years after graduating from college. I know wire. I am not trying to convince anyone of anything and am just enjoying the conversation. I would love to see someone come-up with a theory about cable sound that even looked as if it held water, but again, only as an academic exercise. I have no axes to grind and I'm not trying to convert anyone here. But I will try to correct any technical inaccuracies or any flights of technical fancy.

[gmgraves]

So a well shielded cable is a waste of money?

 

And the same with regard to crosstalk - shielding or insulating conductors from each other is a waste?

 

 

Hardly! Since some RG-59U based audio cables costs less than $5 each, I can't see how one can waste money on them!

[gmgraves]

If we assume that some interconnect or USB cables do, in fact, sound different, then there would appear to be two possibilities. Either the very small measurable differences do have an effect on the brain's auditory function or, if they don't, then some other characteristic - currently unknown or misunderstood - must account for these differences.

 

 

I choose door number 2!

[plissken]

So the better noise floor would be possible even if the balanced and SE cables had the same LCR, yes?

 

The noise floor is a function of the CMNR.

[plissken]

I assume the RF cage would not keep out noise coming through the inputs, though, thus the usefulness of things like shielding and balanced cables.

 

I wouldn't assume that.

 

And what RF noise?

[plissken]

Unless there is added attention paid to the PSU area the results may very well be worse. Add to that the difficult task, due to component tolerances of getting absolutely identical outputs from both halves.

 

Notice I said "can have up to". But to put the argument on it's head: No matter what attention you pay to SE devices you can not gain that "up to" 6dB of additional noise floor improvement.

 

If the noise floor is already astonishingly low with SE connections then as far as noise floor is concerned balanced design is of diminishing value.

 

Again there are a lot of good designs for each. I'll take balanced interconnects when all else is equal and they are available to me. The cost between quality XLR/TRS and RCA's is basically parity from what I have seen.

[plissken]

Look at what you quoted! Less than a quarter of a dB of attenuation at 1 MEGAHERTZ for 100 FEET of cable length. They don't even spec loss at at 20 KHz, because it's entirely negligible!

 

It wasn't lost on me the the starting point of the attenuation sweep started at 1 million cycles per second and only .24 dB of loss.

 

I wonder how many here could listen to a stereo pair of speakers and pick out a .24 dB of loss on one channel across the entire FR band.

[sandyk]

Notice I said "can have up to". But to put the argument on it's head: No matter what attention you pay to SE devices you can not gain that "up to" 6dB of additional noise floor improvement.

 

If the noise floor is already astonishingly low with SE connections then as far as noise floor is concerned balanced design is of diminishing value.

 

Again there are a lot of good designs for each. I'll take balanced interconnects when all else is equal and they are available to me. The cost between quality XLR/TRS and RCA's is basically parity from what I have seen.

 

The attached link quotes Elias Gwinn from Benchmark. It won't just apply to headphone amplifiers.

 

AMB Laboratories DIY Audio • View topic - Benchmark Engineer on Balanced v Unbalanced Headphone Amps

[Jud]

I wouldn't assume that.

 

And what RF noise?

 

Oh, no RF noise, so I expect you to now rail against the waste of money that would be involved in the RF cage you were calling for as a design element just a few posts ago here.

 

And just wondering why the standards call for shielding if there's nothing to shield against.

 

I'd be interested to see the RF cage design that would keep out noise coming in to equipment through input cables.

[Jud]

The noise floor is a function of the CMNR.

 

Exactly. So a potential sonic difference not due to LCR.

[jabbr]

Exactly. So a potential sonic difference not due to LCR.

 

LCR is very much like saying that its all described by Maxwell's eq. The complexity arises because of the complexity of the network. The explanations really come from, essentially, the topology of the network. More simply: while LCR underlies everything, you can't get understanding from LCR alone. Introduction: https://en.wikipedia.org/wiki/Network_analysis_(electrical_circuits)

 

The way I describe this: regarding differences between cables (or more complicated electronics for that matter)

1) we understand the basic measurements

2) we understand impulse responses/transfer functions

 

3) we may not have a proper model/network description of the particular cable

4) we don't have a good understanding about how specific network toplogies relate to perceived sound (SQ)

 

(we have some rules of thumb e.g. prefer even harmonics etc.)

[jabbr]

What I'm saying above is a specific application of the general 'problem' of scientific reductionism -- we have a great ability to make measurements, and a great understanding of the individual components of a system, but have difficulty understanding the system as a whole., in this case going from 'electrons' and 'copper' which we know a great deal about, to SQ which we know very little about (except that we know it when we hear it -- the oft repeated 'trust your ears' )

[kevin1969]

I love the argument here that because a bunch of individual components are hooked together that nobody can possibly understand the system as a whole therefore we must trust our ears to guide our monetary expenditures. I happen to work in the Internet community and I can tell you without any doubt that there is no mystery how the entire internet works together as a whole. There is nobody at any large Internet companies like Google, Level3, Apple or the like that buys into this crap that somehow the quality of a service can magically be improved but not measured. Someone once referred to the high end audio community as deaf and blind ham radio operators. But at least ham radio operators utilize qualitative measurements as a yardstick of performance.

[Jud]

I love the argument here that because a bunch of individual components are hooked together that nobody can possibly understand the system as a whole therefore we must trust our ears to guide our monetary expenditures. I happen to work in the Internet community and I can tell you without any doubt that there is no mystery how the entire internet works together as a whole. There is nobody at any large Internet companies like Google, Level3, Apple or the like that buys into this crap that somehow the quality of a service can magically be improved but not measured. Someone once referred to the high end audio community as deaf and blind ham radio operators. But at least ham radio operators utilize qualitative measurements as a yardstick of performance.

 

Next time any of us has a ground hum we can't immediately diagnose and fix, we'll call you. Meantime, look up "three body problem."

[plissken]

The attached link quotes Elias Gwinn from Benchmark. It won't just apply to headphone amplifiers.

 

AMB Laboratories DIY Audio • View topic - Benchmark Engineer on Balanced v Unbalanced Headphone Amps

 

I'll keep that in mind if I'm ever in the market for a high end HP rig. Thx.