Ethan Winer Builds a Wire Null Tester

[urfaust]

I swear sometimes i feel people in ufo and flat earth stuff are more down to earth than audiophiles, this is crazy these kinds of myths still perdure.

last time i stumbled upon a youtube video demonstrating "ceraball isolators" clamped on top of a DAC. Of course it was supposed to bring very different sound with them, and it looked exactly like ufo's

 

[Ethan Winer]

Thanks very much to Amir for posting this, and to the others for all the great replies. I'll address only one reply for now:

If subject to vibration they [wires] can due to an effect called triboelectric noise. Basically the movement of the conductors against the insulators.

Yes! I also devised a test setup to assess triboelectric noise, and I had planned to include that in my video. But the video is already too long, so I'll probably make a second video just for that. My Null Tester has an input impedance of 10K, which is close to a short circuit for piezoelectric effects. So I used my Fender Sidekick guitar amp, and made a 100K shielded termination for the other end of the wire. When you bang on the wire you can easily hear the noise. Below is a trial test using the Null Tester with the gain cranked up to overcome the 10K input impedance, but you need to be on Facebook to see it. It works better with my guitar amp.

https://www.facebook.com/video.php?v=10156742129220859

 

[watchnerd]

Thanks very much to Amir for posting this, and to the others for all the great replies. I'll address only one reply for now:



Yes! I also devised a test setup to assess triboelectric noise, and I had planned to include that in my video. But the video is already too long, so I'll probably make a second video just for that. My Null Tester has an input impedance of 10K, which is close to a short circuit for piezoelectric effects. So I used my Fender Sidekick guitar amp, and made a 100K shielded termination for the other end of the wire. When you bang on the wire you can easily hear the noise. Below is a trial test using the Null Tester with the gain cranked up to overcome the 10K input impedance, but you need to be on Facebook to see it. It works better with my guitar amp.

https://www.facebook.com/video.php?v=10156742129220859

You are the MacGyver of audio....

 

[Sal1950]

Thanks very much to Amir for posting this, and to the others for all the great replies.

Hi Ethan, good to see you here.
Nice piece of work.

 

[solderdude]

I wonder how problematic the triboelectric noise is for audio as most sources are very low Ohmic, usually less than 100 Ohm.
All generated noise, this way, would effectively be 'shorted', even if it has a 1M input R 'loading' the cable as the source and 'load' resistance are in parallel for audio frequencies (and way beyond).

My 50 y.o. old ceramic element record player connected to a 1M input could be another story but I won't be hammering away on that old cable though.

 

[sergeauckland]

Triboelectricity is a problem for microphone cables in venues, where the cable length can be 50-100m, and the signal can be of the order of microvolts. Choosing a microphone cable that is specified for 'low tribo' is worth using under those circumstances.

For home audio, it's pretty much irrelevant.

S

 

[Milt]

Considering that multi-million dollar companies are built upon this premise is staggering to me.
I think there is a segment that has a continuous need to update their systems and they are not going to update by buying cheaper or the same priced cables.
There has been more than one blind test of mega-buck speaker cables vs cheapie cables.
No reliable identification of either cable, not even coin toss level.

 

[JJB70]

When did balanced cables become popular for home audio? Until not that long ago balance XLR connections were rather rare for home audio equipment and even high end statement products tended to be RCA non-balanced connections. Now it is one of those features which seems to be on lots of want lists.

 

[graz_lag]

... There has been more than one blind test of mega-buck speaker cables vs cheapie cables.
No reliable identification of either cable, not even coin toss level ...

I agree with your comment, however as per my experience in my installation :

Bi-wiring from the amplifier to the loudspeakers.
I have been testing different types of cables, in terms of section ... silver-plated and not ... refrigerated with N2 ... oxygenated with H2O2 ... burned in my garden pizza oven for 2 hrs. ... and so on ... always keeping in mind my principle : cabling should not impact more than 15% of my total installation.
After several tests, also switching the type of cables between the Low Freq and High Freq (bi-wiring), I was forced to admit that the sound out of the loudspeakers was different from one cabling combination to another.
There was not uniformity of feedback form the members of my panel abt. which cabling combination was preferred over the others.
But all recognized the differences in sound restitution.

So at the end, I decided to keep the combination that most suited my taste.

The technical reasons behind the fact that "one cable" impacts the sound in a certain way over "another" are well known.

My recommendation is to test different power cabling to the loudspeakers in order to pull out the most suited one for that particular installation.
Once you have decided the incidence in terms of $ amount of the cabling over your total installation you can easily play within that budget.

 

[Milt]

I started using XLRs when I built out my theater\music room.
I wanted the source gear out of the field of vision which required 30 foot interconnect runs to the amps by the speakers.
My pre-pro and power amps had XLR connections so it seemed the thing to do.
I bought bulk wire and did the terminations myself.
Much easier to run cables through conduit without bulky XLRs attached

 

[graz_lag]

When did balanced cables become popular for home audio? Until not that long ago balance XLR connections were rather rare for home audio equipment and even high end statement products tended to be RCA non-balanced connections. Now it is one of those features which seems to be on lots of want lists.

I have been asking the same question for many years : the XLRs are the standard in studios, so on electronics that are very much involved in the music recording, the same music we play by means of our precious Hi-Fi systems ...

XLR connections are one of the cases of that inconsistency, firewire over the USB is another ...

 

[restorer-john]

When did balanced cables become popular for home audio? Until not that long ago balance XLR connections were rather rare for home audio equipment and even high end statement products tended to be RCA non-balanced connections. Now it is one of those features which seems to be on lots of want lists.

About the mid 80s we started to see XLRs on TOTL digital home HiFi gear coming from Japan. There may be a few examples prior, but I can't recall any.

The Sony CDP-X7esD (1989) was the first to incorporate XLRs from that company on a TOTL machine (although built by their broadcast equipment division, they no doubt knew it was used in professional installations as a reference). It used a dedicated pair of LCOFC shielded balanced transformers on a sub board for the XLRs (no cheap op-amps).

My Marantz CD12/DA12LE (1990) has XLRs driven by dedicated transformers too.

Accuphase in Japan had been putting one or two pairs of XLRs on their TOTL preamplifiers around the same time. Most of the 'balanced' inputs on gear were (are are in many cases) simply an additional opamp in front of the normal input, an as such, their performance degraded in many cases. Now we are seeing true balanced amplification, but for domestic short run use, I fail to see what gains (pardon the pun) can be eeked out.

For audiophiles, it became a badge of honour and although most weren't using them, they had to have them on their latest kilobuck toys. It made them feel more 'pro' and the manufacturers knew it.

 

[DuxServit]

Thanks very much to Amir for posting this, and to the others for all the great replies. I'll address only one reply for now:



Yes! I also devised a test setup to assess triboelectric noise, and I had planned to include that in my video. But the video is already too long, so I'll probably make a second video just for that. My Null Tester has an input impedance of 10K, which is close to a short circuit for piezoelectric effects. So I used my Fender Sidekick guitar amp, and made a 100K shielded termination for the other end of the wire. When you bang on the wire you can easily hear the noise. Below is a trial test using the Null Tester with the gain cranked up to overcome the 10K input impedance, but you need to be on Facebook to see it. It works better with my guitar amp.

https://www.facebook.com/video.php?v=10156742129220859

@Ethan: thank you for your hard work and for the video. I watched the entire video and found it very usel and educational.

PS. Is your cat an audiophile too?

 

[restorer-john]

I well remember this, HK's Citation XX (1982/3/4), had XLRs on the back of it.

 

[graz_lag]

For audiophiles, it became a badge of honour and although most weren't using them, they had to have them on their latest kilobuck toys. It made them feel more 'pro' and the manufacturers knew it.

There are "audiophiles" as well as also "idiophiles" ... who are a sub-form of the former ...

The XLR balanced connections are "mandatory" if your source (CD player or DAC) creates a true balanced signal by spitting the signal in the digital domain, then - if, the balanced digital signal is converted to analog by two DACs per channel and output from the source on balanced XLR connectors, at that point you should continue on that true balanced topology down to the power amplifier.

If one of your electronic being connected (out of the 3 into the chain : source, pre, power amplifier) is not designed as truly-balanced, your best approach should be the one of using the RCA connections.
At least you avoid the damage created by the phase-splitters, differential amplifiers, op-amps ...

 

[graz_lag]

I well remember this, HK's Citation XX (1982/3/4), had XLRs on the back of it.View attachment 17551

Have been aging thru 3 mythes :

#1 The Lancia Delta Integrale, which I am still owning (red with the Martini decals, of course ...)
#2 The Saeco Team Cannondale CAAD race bike (Cipollini's edition), which I had for some time ... but not anymore ...
#3 The HK Citation XX, which I never own ... so I bought the little son of it in 2011, the HK 990 (integrated amplifier) ...

 

[sergeauckland]

There are "audiophiles" as well as also "idiophiles" ... who are a sub-form of the former ...

The XLR balanced connections are "mandatory" if your source (CD player or DAC) creates a true balanced signal by spitting the signal in the digital domain, then - if, the balanced digital signal is converted to analog by two DACs per channel and output from the source on balanced XLR connectors, at that point you should continue on that true balanced topology down to the power amplifier.

If one of your electronic being connected (out of the 3 into the chain : source, pre, power amplifier) is not designed as truly-balanced, your best approach should be the one of using the RCA connections.
At least you avoid the damage created by the phase-splitters, differential amplifiers, op-amps ...

A 'true balanced' power amplifier is a nonsense. To be 'true balanced' it has to maintain common mode rejection to at least 60dB throughout the full frequency range and all power levels and loads, which is one hell of a tall order. Far better is to use an opamp input, which can easily maintain that sort of CMR, then follow it by a conventional 'unbalanced' power amp. Loudspeakers REALLY don't care if they're driven differentially or asymmetrically. A transformer will do as well, but one that can better an opamp is expensive.

There's just so much crap talked about balanced!
S

 

[restorer-john]

...Thanks very much to Amir for posting this, and to the others for all the great replies...

Cool you are still using the old Radio Shack benchtop multimeter, I was selling them new in 1989~ when running a Tandy store as 22yo!

Turn off autoranging and hold down the relative button until it beeps/zeroes. The fixed test cable will be zeroed out and the cable under test will show just its value- saves doing the maths.

 

[SIY]

There are "audiophiles" as well as also "idiophiles" ... who are a sub-form of the former ...

The XLR balanced connections are "mandatory" if your source (CD player or DAC) creates a true balanced signal by spitting the signal in the digital domain, then - if, the balanced digital signal is converted to analog by two DACs per channel and output from the source on balanced XLR connectors, at that point you should continue on that true balanced topology down to the power amplifier.

If one of your electronic being connected (out of the 3 into the chain : source, pre, power amplifier) is not designed as truly-balanced, your best approach should be the one of using the RCA connections.
At least you avoid the damage created by the phase-splitters, differential amplifiers, op-amps ...

Be careful not to conflate differential with balanced. Good balanced connections do not have to be differential, they just need to have the same source impedance on each leg.

 

[graz_lag]

A 'true balanced' power amplifier is a nonsense. To be 'true balanced' it has to maintain common mode rejection to at least 60dB throughout the full frequency range and all power levels and loads, which is one hell of a tall order. Far better is to use an opamp input, which can easily maintain that sort of CMR, then follow it by a conventional 'unbalanced' power amp. Loudspeakers REALLY don't care if they're driven differentially or asymmetrically. A transformer will do as well, but one that can better an opamp is expensive.

There's just so much crap talked about balanced!
S

This is the one I bought (the 2-channel version), tested and compared over bridged amplifiers from the same manufacturers ...
https://ati-amp.com/AT6000.php