Did Amir Change Your Mind About Anything?

Has ASR actually changed your opinion on anything?

Yes, I think so. I'm an electronic engineer and have repaired broken audio equipment. I always had to measure before (if it's working sufficiently) and after to confirm I'd fixed the problem. With this skill and knowledge it's hard to live in the purely subjectivist world. For example, I have seen repeatable evidence that well designed audio has an inherent ability to reject mains-carried noise and that (as long as it's well made) a mains cable can not change how a piece of well designed electronics works.

What have I learned from @amir_asr  ? The courage of my convictions! Also, like the OP, to not be surprised that I can hear a difference when I make a change, but to check that the change is real and if so, valuable,

@tjag said

Do you people ever do listening comparisons?

First of all, how dare you classify me as "you people"? You know nothing about me, you merely make yourself look small and mean.

Secondly - I do listening comparisons. I've also worked on thousands of different bits of audio kit using measuring tools - because it was my job! You cannot return a bit of repaired audio kit without first proving you've eliminated the reported problem and ears+brain are insufficient for that task, you have to use signal generators, meters and audio analysis kit. I also used to play some music to check all was OK.

I've encountered a great deal of genuinely faulty kit which still sounds OK-ish, ears+brain are a very low grade mechanism for checking things are not broken...

maxwellseq

25 posts

05-21-2022 at 04:25am 

1. SPDIF must use a coaxial cable.
2. SPDIF characteristic impedance of the cable must be 75 Ohm
3. SPDIF cables are often orange
4. It's a digital signal and as long as the cable is well made, there should be no difference in errors and so no difference in sound

I personally like #3 😉

As long as 1 and 2 are observed the colour is irrelevant, of course, But some manufacturers seem to colour code them so people don't accidentally plug them in the wrong hole. It's not the case for all kit I've seen, but I've bought three digital products which were shipped with an orange cable for S/PDIF in the box. Perhaps it's an EU thing?

It's a real pity S/PDIF uses Cinch/RCA, since BNC would have been better and less prone to mistakes.

S/PDIF is just a protocol. It can be used with RCA, BNC, or optical connectors.

Absolutely, but most manufacturers have utilised RCA, and there is always a problem if a manufacturer does use BNC: people would complain that their other kit is RCA and they have to use an adaptor. So marketing would wonder why the engineers have picked a technology that annoys customers!

ghasley

07-02-2023 at 02:17pm 

@maxwellseq Just curious what point you are trying to make.

I wasn't trying to make a point. Someone quoted me from a different thread - about S/PDIF - in this thread, and I clarified. It was off-topic; I should have not responded.

alanhuth

07-07-2023 at 09:41pm 

Yes, he did change my mind, about power cables.  He proved, using signal subtraction, that the signals generated by devices from different power cords are identical.  Any difference you heard is confirmation bias, as the signals feeding the amplifier are IDENTICAL

I’m disappointed nobody responded to this observation.  Do you guys agree that Amir is right about power cables?

He didn't change my mind about power cables. I already knew enough electronics engineering to know that if safe and sensibly designed, they can't affect properly designed audio kit performance.

What @amir_asr has also shown (if you read further than the headlines) is that even he sometimes hears a difference when he changes things, but that the perception is unreliable and an effect of perceptual heuristics.

mapman

07-08-2023 at 05:08pm 

I can only speak for myself but the problem at hand for most here on this thread I think is how to best choose what to buy. Measurements are very useful for that. Explaining why human hearing is so complex is totally useless towards that end. It is useful to understand how human hearing works to help better understand why we hear what we do. But these are two totally different use cases. What is of value always depends on context. So there really should be no debate. Two totally different sets of information used for two different but related purposes. Best to understand it all but no point in arguing one versus the other. One topic at a time please!

Well put