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Is the entire audio industry a fraud?

How about showing the ABX comparator unit itself, not some vague description of a ficticious device buried in your basement, and the show the unit you claim to have taken to your friend's place for the other ABX test you claimed to have completed.

I'm calling absolute bullshit on your claims.

Put up or shut up.
Seems you are a quite unpolite, unpleasant and upset man :facepalm:
Why not asking me friendly to show what I did after my post?

I‘m traveling in South East Asia till end of April so I‘m not able to shoot and send photos. So at the moment you can believe me or not I don‘t care at all.

Here you can see my full range horns I was talking about but I think it won‘t increase my credibility in your brain…
Edit:

This is the NCx500 Amplifier I bought. I ordered a custom build with one power supply only as the full range drivers have 16Ohm so I need voltage without much current.
 
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Sorry, I try to give a short reply as it off topic here ;)
Here the steps I took to make the ABX as fair as possible:
  • I calibrated the horns independently for each amplifier to the same target with the Acourate software. This is important as using a resistor in series to the full range speaker the rising impedance of the chassis increases sound level towards the higher frequencies.
  • As the Krell has a much higher amplification than the NCx500 (26 to 11dB) I calculated a voltage divider with tree resistors and soldered it in the XLR plug I connected to the Krell. I used a Y-cable to send the same audio to both amplifiers.
  • After that I did another measurement with my Earthworks measurement mic to check the volume (at the listening position for both channels) and adjusted the voltage divider so both amps produce the same volume in a range of +-0.2dB.
  • For ABX I wrote a small program in node.js for a Raspbarry Pi controlling eight relays that connect the speaker cables to one of the amplifiers only. The PI and the relays were in my basement so I could not hear any click of them, same as the amplifiers. The software disconnects the speakers for 50ms before reconnecting it so I know that they got switched.
  • On my iPad I was able to start ABX via the browser during playback from Roon. Each single ABX comparison was started manually and switching from A to B to X also. So I was able to repeat the track I heard after switching.
  • I ran it 10 times with 15 ABX each time with different musical material.

At the end I got a correct result of 10 out of 10 correct answers for all 15 rounds :)

Maybe there was some issue in my setup or methodology I did not think about so I would appreciate your comment.

Best DrCWO
Further checks I would suggest are:-
  1. Don’t level match using a mic at the listening position. Instead, do it using a voltmeter at the loudspeaker terminals with a 1 kHz sine wave tone. Much more accurate and repeatable.
  2. Do the above with each speaker separately, if listening in stereo during the tests. It is possible that one or both of your amps have a left-vs-right channel mismatch.
  3. Measure the frequency response of the signal at the loudspeaker terminals, with each amp connected in turn. It is quite possible that your particular specimens of the two amps don’t have the same frequency response when connected to your speakers, and the difference is large enough to be audible. In other words, your specimens might not be in perfect working order and have the exact frequency response of perfect specimens of those amps.
 
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After that I did another measurement with my Earthworks measurement mic to check the volume (at the listening position for both channels) and adjusted the voltage divider so both amps produce the same volume in a range of +-0.2dB.
This is not precise enough. An overall level change of 0.2dB is audible (though usually perceived as a quality difference rather than a volume difference). Matching must be done by electrical measurement at the speaker terminals, as Newman has already pointed out.
 
  1. Don’t level match using a mic at the listening position. Instead, do it using a voltmeter at the loudspeaker terminals with a 1 kHz sine wave tone. Much more accurate and repeatable.
  2. Do the above with each speaker separately, if listening in stereo during the tests. It is possible that one or both of your amps have a left-vs-right channel mismatch.
  3. Measure the frequency response of the signal at the loudspeaker terminals, with each amp connected in turn. It is quite possible that your particular specimens of the two amps don’t have the same frequency response when connected to your speakers, and the difference is large enough to be audible. In other words, your specimens might not be in perfect working order and have the exact frequency response of perfect specimens of those amps.
Thanks‘ for your feedback.
Did matching separate but not with a voltmeter. Also frequency measurement for equalization can be done at the speaker terminals instead with the mic as I did.
Good hints I'll respect next time I do ABX :)
 
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If a guy hand builds speaker cables with expensive machined terminations and beautiful construction yet have no measurable or audible improvement over standard mass produced cables and he honestly believes that his cables sound better, is he a fraud? Is he ripping people off?

This is not a science question. It is one of semantics and ethics.

While I personally feel far too many audiophiles waste money of cables, if it makes them happy to buy into the magic show how is that fraud?
Fraud is deliberate. The cable true believer wouldn't be committing fraud if he truly believes in his heart-of-hearts that his cable or whatever does something valuable.
 
Fraud is deliberate. The cable true believer wouldn't be committing fraud if he truly believes in his heart-of-hearts that his cable or whatever does something valuable.
No just incompetent.
Keith
 
Fraud is deliberate. The cable true believer wouldn't be committing fraud if he truly believes in his heart-of-hearts that his cable or whatever does something valuable.
I would suggest that any cable supplier to "believes" in the improvement is doing the same as Nelson at the battle of Copenhagen.

"I see no ships"

There is plenty of evidence out there of the complete lack of impact that cables have on sound quality. Anyone making them - and therefore understanding how and with what they are made, must have done some sort of measurement to understand why their cables are better than others - or they are just being disingenuous.

Since we know that measurements will never demonstrate an improvement, they are - IMO - all being at best disingenuous. At worst - outright liars and fraudsters.
 
I would suggest that any cable supplier to "believes" in the improvement is doing the same as Nelson at the battle of Copenhagen.

"I see no ships"

There is plenty of evidence out there of the complete lack of impact that cables have on sound quality. Anyone making them - and therefore understanding how and with what they are made, must have done some sort of measurement to understand why their cables are better than others - or they are just being disingenuous.

Since we know that measurements will never demonstrate an improvement, they are - IMO - all being at best disingenuous. At worst - outright liars and fraudsters.
Well, funny enough it doesn't take any knowledge of electronics at all to build a fancy cable, listen to music through it, convince yourself it improved the sound, and market it as such. Which sort of tells you how credible the entire space is in the first place...

But unfortunately I don't think we can really say that all cable vendors are being disingenuous, it's entirely possible that many of them are exactly as ignorant as they appear.
 
In the environment of "everything has an impact", then minuscule, expected difference (which are in reality beyond human detection) become "significant". All engineers know cables all perform differently, but we also know that these differences can not be audible.
 
I would suggest that any cable supplier to "believes" in the improvement is doing the same as Nelson at the battle of Copenhagen.

"I see no ships"
I was thinking Baghdad Bob, but I can go with this. :D
 
This is not precise enough. An overall level change of 0.2dB is audible (though usually perceived as a quality difference rather than a volume difference). Matching must be done by electrical measurement at the speaker terminals, as Newman has already pointed out.
0.2dB audible / perceivable? Not in this universe ;) We're talking about a 2.3% amplitude difference.

Cheers,
JaapD.
 
0.2dB audible / perceivable? Not in this universe ;) We're talking about a 2.3% amplitude difference.

Cheers,
JaapD.
Yes, actually in this very universe. You need matching to .1 db to be sure it isn't corrupting results.
 
Yes, actually in this very universe. You need matching to .1 db to be sure it isn't corrupting results.
Do you possibly have any scientific evidence available of this statement? In line with this topic, ABX validated ;)

Cheers,
JaapD.
 
Do you possibly have any scientific evidence available of this statement? In line with this topic, ABX validated ;)

Cheers,
JaapD.
I've found it before and posted the info here, but don't have it at the moment. It was from a paper at the AES I think. I seem to recall it was David Clark. Some earlier work suggested with music you had to have .2 db matching. It might be that Clark found with test signals it was .1 db and .2 db with music. I think someone else later tested a group and also found a difference of more than .1 db was discernible even with music. It is also possible it was an AES paper by Tom Nousaine.
 
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