That dreaded SMT sound

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For an objective existing change in sound, there are three easily measurable properties, that should change. Either distortion level, signal level deviating from linear or harmonics distribution. How we attribute level deviation across audio bandwidth:

Sound perception.png


Most humans can detect sound distortion from -40 to -50 dB levels (1% - 0.3 %). IIRC, during first mass data gathering, it was determined that there are rare examples with up to 20 dB better ability. So, up to 0.03%.

It is also often mentioned that H2 distortion with little or no H3 and upper harmonics, is perceived as warm sound. Dominant H3 with little H2 is often perceived as sharp or even shrill sound.
All that parameters are now easily measured with entry level hobby equipment up to -140 dB levels. Yet, we are repeatedly presented with story that with single component change, sound has changed as well, but no measurements can confirm that. Right.
Proper route would be to measure and compare two different sounding designs.

Different resistors do have different distortion, but effect is barely measurable with professional equipment.
 
Fallibility is a part of human nature. No human being is infallible: lack of exposure, lack of understanding and lack of knowledge make human judgement more subjective and hence, tending more to fallibility. Experts who have studied, have certification and who have a good reputation of truly understanding their disciplines are usually more objective.

My comment cannot be taken as dogma, but obtaining accurate information is often a saver of time, money, and effort.
 
Demonstrate the rigueur you used in your blind testing so we can see how valid your experience is.

The human ear is a REALLY POOR analytical tool, and the human brain is really good at filling in missing details. You've simply let your brain trick you. Don't worry, we've all done it. As soon as you realise you've tricked yourself you'll be able to start developing strategies to avoid it in future.

You've read posts from people who have already come to that realisation and from those who haven't yet.
 
Deleted my post as posts are edited while we speak ("smug" to "satisfied"🙂) making matters personal which is both unnecessary and low. It is a silly discussion anyway.

Please think of the suggestion to repeat the test with parts by a reputable brand and maybe thread titles could be less provoking as well. Imagine "That dreaded Pass Labs sound".
 
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If it doesn't sound the same it is a part you changed. The question is always what did I do, and what am I hearing?
We test to confirm what we hear if there is a problem. WAIT and keep listening. Check your work and rest your ears.
I have always heard changes as the parts are used longer. I have also had tired ears with more or less ambient noise
as a factor. You don't need to prove anything you need to fix it. I'm with you, it's the expectation.

Day one on some of my DIY were horrible, usually cleaning a board, recheck and tighten cabling. PATIENCE and a
couple of days. I'm not a big fan of the first 1-200 hours of listening unless someone already did it. Especially if teflon is involved. Resistors? They are the heart of different or the exact same sound in the analog world. It is an art to swap a 2 dollar resistor and change the whole way a circuit sounds.

I say don't be so fast to tear back into it. No smoke? Be patient and check your work.

I don't want to be to critical I'm a new poster, but QC on parts is pretty important. I don't mess with progress to much.
I'll spend the extra hour looking and the 5 extra dollars in leu of pain in my backside. 🙂
 
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Deleted my post as posts are edited while we speak ("smug" to "satisfied"🙂) making matters personal which is both unnecessary and low. It is a silly discussion anyway.

Please think of the suggestion to repeat the test with parts by a reputable brand and maybe thread titles could be less provoking as well. Imagine "That dreaded Pass Labs sound".
I do want to change the thread title to 'smt resistor sounds different?'. How do i do that?
 
Demonstrate the rigueur you used in your blind testing so we can see how valid your experience is.

The human ear is a REALLY POOR analytical tool, and the human brain is really good at filling in missing details. You've simply let your brain trick you. Don't worry, we've all done it. As soon as you realise you've tricked yourself you'll be able to start developing strategies to avoid it in future.

You've read posts from people who have already come to that realisation and from those who haven't yet.
Yes, yes, yes! I have learned this the hard way... don't trust your ears when there is any potential for expectation bias!
I bought this super-duper cable for my headphones, and it sounded so much better than the stock cable -- until I did a blind test with a friend. 🙄
Please try to compare the sound you get from those two boards in a blind test. You might need a bit of help from a friend who randomly switches between the two boards, without you know which board is in use. Then you try to tell which board it is only by listening to the sound (no other information allowed). Your friend keeps a record of which board was in place, and what you said. There must be no feedback from your friend about your ability to (not) pick the correct answer. Repeat this about 10 times (or more), then take a look at the results. You could share them here so add a bit of substance to the discussion.
(Just for reference, my ability to tell the right headphone cable was worse than that of a deaf amoeba working on a random number generator.)
 
I have no problem admitting that i made a dumb mistake assuming to know what the issue with my design was. Can you Jean-paul at the same time stop jeering at the said mistake so that i can hopefully get some constructive criticism?

The non psu caps on my smt build were also generic parts. Now im wondering if they are the culprit and if caps generally contribute more noise than resistors in a typical linestage circuit
 
It is also often mentioned that H2 distortion with little or no H3 and upper harmonics, is perceived as warm sound.
H2 can add or cancel with downstream components depending on absolute phase. Acoustic transducers almost universally generate H2. The 'objective' stance that an upstream component with additional H2 adds warmth is never confirmed by measurements showing an increase in H2 reaching the ear or transducer.
 
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