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Mains supply and HiFi

One of the things Audio Conversions garnered is "if it sounds better it IS better".

Great audio engineers have stressed that the final arbiter should be your ears.

That can clash with logic. Person 'A' declares the sound "marvelous and improved". 'B' says "mediocre in comparison". 'C' states: "it's now rubbish".

Q. Who is correct?
A. A,B, & C.

Moral: Don't be afraid to be D.
 
a.palfreyman said:
Sorry Jez, I respect your views, but just reporting what I hear so I have taken SQ's advice. I have cleaned the plug terminals, taken both leads (pre psu and original power amp lead) and cut the ends off and tinned them so they are nice and fresh...
Click to expand...

If we're paying attention to mains wiring, this recent thread (mine!!) might be of interest.

https://pinkfishmedia.net/forum/threads/spade-crimp-terminals-versus-ferrule-terminals.256731/

Tinning/Soldering flex is not recommended.

(I'm not touching the primary topic with a bargepole!)

BugBear
 
And capacitors don't make any difference either! There ...I've said it...
And while I'm at it....bits are just bits...ones and zeros..
And a resistor is just that....
 
Mynamemynaim said:
And capacitors don't make any difference either! There ...I've said it...
And while I'm at it....bits are just bits...ones and zeros..
And a resistor is just that....
Click to expand...

The horror of it...

Certainly there are badly made capacitors that dry out in the wink of an eye, or let out puffs of vapour at slightest provocation....
 
sq225917 said:
Just measure the output coming from the connected device, if anything crops up between 0-120db you've won a prize.


But it won't, because it doesn't make a difference, if it did then at least one company in all of hifidom would have used it in their marketing in the past 30 years, wouldn't they? The closest anyone gets is shenyang showing that mains filtration units lower noise by a few dB in very, very sensitive electrocardiogram machines.
Click to expand...
If someone hears something different from changing mains supply I won't dispute what they hear. But interestingly there is a recent test here where mains input ranging from "very clean" to "very dirty" was supplied to three different audio devices. The audio output was measured down to better than 140 dB below maximum to see how much impact very dirty mains made.

No difference was seen regardless of the quality of the mains input.

So there is good evidence that at least three pieces of audio kit can be immune to very bad mains to a level well below audibility. This does not mean every piece of audio kit is immune. But it shows that it is possible. And if it is possible I personally would be unhappy to settle for anything less. But people do have different goals in this hobby,
 
I've done quite a few subjective fully sighted and hopelessly biased tests with mains configurations. I think I spent about £50 for materials to do the tests.
I hear differences between different materials and configurations.
My final preferred solution is very simple and uses basic materials.

I would encourage anyone who is interested to do your own experiments.
 
Already done. Twenty years ago.
Maybe I’m biased but I couldn’t hear anything – of course.
Since then I’ve lived in peace, focusing only on my beloved equipment and my music.
 
[QUOTE=
"...No difference was seen regardless of the quality of the mains input...."
* EXTRACT from John Phillips*

N.B. It does not say: "...No difference was HEARD (etc.)"

Why do these people test measurements, only, when the object of reproducing music is to hear how realistic the sound is compared with the original? I suspect that the tester- with her arsenal of impressive test equipment- operates by carrying baggage containing some heavy presumptions or preconceptions- in addition to the weight of her test gear.

I do hope she went home without a hernia.
 
..because it is important to remind oneself where your choices may be rooted in (or unhinged from) reality?

It's easy to 'hear' improvement, upon improvement, upon improvement. I bet every regular poster in DIY would admit to chasing a rabbit hole or two like that at one time or another. I do.

It becomes a much-more interesting problem of cognition when you also know -that change was hilariously- beyond your ability to hear, let alone claim-to-hear (likely 1/10000th or less of the noise floor of a *good* recording, as demonstrated in the test referenced by @John Phillips .)

No, I do not believe human ears are that good - in fact they simply cannot be, for very-well understood physiological and environmental reasons.
/and/
Yes, as Lord Kelvin said on music - '..in all matters things finally come to the ear for judgement'. But a large part of that is irrational and pragmatic choice, in other words .. personal taste.

And that is fine - it is all very personal.

But the subsequent ability to claim '..but this is better' against measured results, is equally limited by that singular scope.
 
... and here's a very,very much more concise old 4-panel comic making a simple but more pungent point about ... sufficiency of contentment: to take it where and when you find it.

;)

calvin_hobbes%20sunny%20field.jpg
 
I think that @John Phillips may have the answer in para 3 above. I've been reading AN202 (IIRC the number) and don't profess to understand most of it, but it makes a good point about common mode noise. My psu cap banks are DIY versions of mini cap 6 modules and the output return and zobel go to the centre tap end whilst the amp input referenes to the opposite end of the 0v plane which is I believe how most are connected. However this introduces common mode noise across the finite resistance of the 0v plane which will pull the front end 0v reference up and down with both unsymmeyrical charging currents and the current returning from the load as it returns to each capacitor in the bank. This would also surely make it more susceptible to mains quality?
 
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