John Curl's Blowtorch preamplifier part II

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Yes, well, IF the pack is going to hare off in that direction it would do well to remember that non-linear distortion is masked with increasing SPL.:eek:

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Why does choral music make so many sound systems sound like shite?
Because they are shite, :p ...

I'm afraid so, full bore choral music brings all the distortion artifacts to the surface, the problems can't be ignored listening to this type of recorded material. Increasing SPL places greater and greater burdens on the brain to unravel the sound - too much distortion, too much harmonic complexity ... and it's a disaster to listen to.

The key thing is, that eliminating the distortion mechanisms solves all these problems - you can put on any sort of music, at any volume, and it all works ...
 
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Not at my place.

In his Linear Audio article Dick Burwen explained that placing a water glass in a different spot on the lounge table already could cause dB's of changes in some parts of the freq response at the listeners position.

These things DO matter in really controlled tests.
One reson why Harman went to great length (and cost!) to contruct a pneumatic 'speaker shuffler' to move each speaker in exactly the same physical position during comparative listening tests.

Jan
 
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I find your prejudices alarmingly arrogant, attitude should be humble and mind should be open.

" Arguing with a scientist is like wrestling a pig in mud; After a while you start to realise that they are enjoying it"

Many on this forum not only are fully trained in the Scientific Method, but use it every day. That is not prejudice, but a true search for knowledge. Those not trained this way may not see it that way, but are happy to go through life using shiny stuff that without SY and his ilk couldn't be made.
 
Yet all changes when you change a cable or place the "box of gain" on a different stand. Or you double the psu capacitance, yet the sine is the same, distortion remains the same. Just that the music is performed different, with different tempo and emotions. All is not measurable or we don't know how to measure it, or we don't know how to measure music performance. That is much much more subtle than something having great spechs.

If putting your amp on a stand changes the tempo of the music, either something is seriously wrong with your equipment, or the tempo change is happening inside your mind.
 
In his Linear Audio article Dick Burwen explained that placing a water glass in a different spot on the lounge table already could cause dB's of changes in some parts of the freq response at the listeners position.

These things DO matter in really controlled tests.
One reson why Harman went to great length (and cost!) to contruct a pneumatic 'speaker shuffler' to move each speaker in exactly the same physical position during comparative listening tests.

Jan
Bingo!! ... the singing bowls effect, discussed some pages ago ...
 
Did you just call SY a pig..??
I too am a trained engineer, MSc, and the harder I work to find answers, the more I realize that our hearing threshold is vastly superior to any measurement device. I also believe that we can measure most anything, but the hard part is what to measure in order to make a correlation between how a system performs music and the objective measurements.

Claiming that a System is indifferent to cables is like saying hey placing a different microphone in the signal path doesn't matter.. Any cable is a mighty fine microphone as it contains reactive elements and it is moved with the airmotion. Now if the competent gain boxes fail to show that, they are truly incompetent
 
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Unfortunately, there can be an effect - in hindsight, one of the reasons I struggled with my first achievements in "good sound" was highly likely this - but I was totally unaware of this "fetish", and never tried any experiments along these lines.
Yup, get cables off the carpet.

It's a materials effect, and a mongrel of a thing to get a grip on - as good a reason as any for going fully active, say, to bypass the whole nonsense ...
Materials proximity effect....once heard, never forgotten.

plastic-bar-chairs

Plastic_Bar_Chairs_Combination.jpg

Dan.
 
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Did you just call SY a pig..??
I too are a trained engineer, an the harder I work to find answers, the more I realize that our hearing threshold is vastly superior to any measurement device. I also believe that we can measure all, but the hard part is to make a correlation between how a system performs music and the objective measurements. Claiming that a System is indifferent to cables is like saying hey placing a different microphone in the signal path doesn't matter.. Any cable is a mighty fine microphone at it contains reactive element and it is moved with the airmotion. Now if the competent gain boxes fail to show that, they are truly incompetent

Civil engineering perhaps?

I will give you £1000 if you can make an intelligible recording of a musical instrument using 1m of any audiophool cable of your choice.

Sure, enough teflon and thwacking with a hammer will register a pulse on a scope, but that is not the same as saying playing music at home will cause modulation of the signal by the cable. If it does then you have just proved the case for balanced interconnects.
 
No not civil engineering thank you,

Balanced has its own set of problems, but in general difference signals are the most robust.
How dou you know when something is not important,
How can you ignore something that scientifically exist and call it a non issue, and the at the same time call yourself objective. What do we really know about signal transfer... A stream of electrons, a wave of energy, does surface matter, does conductivity, does ground impedance matter after all that is what sets the reference between components, can w hear a buffer..? Can we hear 10, or a hundred..?
 
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No not civil engineering thank you,


How dou you know when something is not important,
How can you ignore something that scientifically exist and call it a non issue, and the at the same time call yourself objective.

When the effect is more that 100dB down from the signal I would say its not important for me. If I get my end to end chain better than that I might move the goalposts, but for now I can build an analogue chain end to end to around that level then hit a speaker that is 30dB worse. I know where I need to sweat to improve things. YMMV.

When I was 20 I worried about cables etc. But I got better.
 
Good for you, did that ignorance grow with the loss of hearing too..?

Fair enough to work the hardest on the 20% that matters the most, but that does not render the last 80% being out of any significance.
Hell it matters a lot weather I make a magnet system with ferrite neo or alnico, while they can measure the same, they will sound different. Here we clearly measure the wrong elements. As it's not the steady state that changes but pure dynamic phenomenons.
Same goes for twice the PSU supply capacitance, or a by design better PSSR. It may not change the measured performance but it will change the listening impression on the system.
 
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Trouble is, no-one is measuring "better", using the "better" equipment - because it has been "proven", :rolleyes:, that vaguely good enough is good enough, in "scientific" tests, no real effort is being made to improve things ...

AP are likely to argue with you. The fact that their AP5xx series is selling very well suggests that people DO want to measure better. The fact that AES has not folded due to lack on interest also suggests there are still plenty out there who want to advance the state of the art. Even the Gedlee papers referenced a few pages ago, which are fascinating are pushing the limits to understand what makes great audio. But science is not enough for some who want to believe. I have no problem with believers, just they keep trying to convert others.
 
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