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Old 6th December 2012, 02:42 AM   #30901
SY is offline SY  United States
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Quote:
Originally Posted by john curl View Post
Thanks SY, for the encouragement.
I've encouraged you many times to try doing ears-only tests. I still do, though I'm pretty convinced that you won't trust your ears and do it. That's certainly your right, but it does make it appear as if you're not exactly convinced that you really can hear the difference between an expensive, well-engineered preamp and a cheap well-engineered preamp.
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Old 6th December 2012, 02:53 AM   #30902
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Perhaps, and I could be wrong in this, John's hearing at his age is just not what would be required to do double blind testing and be useful for a listening test? Unless someone actually still has acute hearing and has upper registry that can even get up to if not over 16Khz how can you count on their listening and evaluating at this level of differentiation. I have known many guys that even in their 40's had such hearing loss due to environmental factors as to make what they thought sounded good, useless.
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Old 6th December 2012, 03:00 AM   #30903
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Originally Posted by Esperado View Post
I think you don't understand my point Nothing sound like "the real thing". For such a reason that the real thing does not exist. None listen the same thing in a concert hall.
What I said was, 'subjective reaction of "it sounds like the real thing"'. Meaning, you can be fooled into regarding what you're hearing as being equivalent to the live experience. 99% of hifi's always sound like a hifi, especially when you get reasonably close to an individual speaker; I'm talking about getting past that point. At the hifi show I just went to there was just one system that was capable of reproducing drum kit instruments correctly, none of the others stood a chance of doing that. And that's what I want ...
Quote:
As i said, i'm a sound engineer, the most near the real thing you can imagine. Right ? Original tapes of mine i can compare, listening with the best equipments as possible.

What i said is it is easy to build a preamp, using some current feed-back OPAs, with some care near the power supply, and to get as close to the original as possible. At least with less deterioration than any other part in any system (power amps, enclosures, most of the commercial DACs ).
I sure you're closer than many, but in my experience it's very difficult to close the gap between 98% and 100% SQ. When it happens, you certainly know it; one of the reactions can be that the real thing no longer sounds as good as the reproduction!! Why, because the mic's when recording are placed absolutely optimally, usually, to pick up all the detail in the sound, which is often not where you are when listening live ...

Frank
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Old 6th December 2012, 03:27 AM   #30904
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Originally Posted by fas42 View Post
At the hifi show I just went to there was just one system that was capable of reproducing drum kit instruments correctly, none of the others stood a chance of doing that. And that's what I want ...
Zillion slew rate current feedback everywhere you can, including Power amps, spherical horns with good drivers (i Know only one), two ways (time aligned) in your enclosures (with added sub if you like), high efficiency, comfortable margins of power, digital active filters with flatten response curve and group delay alignment of your speakers is the way i suggest, with the necessary acoustic treatment of the listening room:-)
Did-we agree on that ?

Nb: Not so easy for somebody witch does not build his own system and is stuck with commercial products.

The difference between us is i don't believe, or dream, of 100%. The question remains about what is the 98% of one and the 100% of an other.
For me, as long we will be stuck with actual speakers technology, hifi will remain junk, in some ways. :-)
Sometimes an agreeable or impressive junk, yes.
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Last edited by Esperado; 6th December 2012 at 03:35 AM.
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Old 6th December 2012, 03:43 AM   #30905
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Serious people making serious listening:
Simplistic NJFET RIAA

Note they have preferred a Solid state current feed-back amp to their tube's one.
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Last edited by Esperado; 6th December 2012 at 03:46 AM.
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Old 6th December 2012, 03:45 AM   #30906
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Originally Posted by Kindhornman View Post
Perhaps, and I could be wrong in this, John's hearing at his age is just not what would be required to do double blind testing and be useful for a listening test?
John claims he can hear the differences. Now, at his age. His eyes are irrelevant for hearing.
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Old 6th December 2012, 04:38 AM   #30907
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Originally Posted by Esperado View Post
Not so sure: We had tried this joke near a well known reviewer, during the listening session with some real other preamps.
The wire was not the winner, according to his notes :-)
We were not in so good relationship with him, after having revealed the trickery :-)
Trickery???

Good ears consist of 2 capability: (1) Differentiate 2 sound sources (2) Decide which one is "preferable".

If a straight wire is what we want, why use preamp at all? We need preamp because we need to boost details/dynamics that is not available with straight wire. But we want the performance of noise and distortion as good as a straight wire.

If you do blind test with common people (especially with a system which is naturally far from perfect), a straight wire should NEVER win. Most of us will have difficulty in deciding between too little, enough or too much of everything.
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Old 6th December 2012, 07:36 AM   #30908
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Thank you, kindhornman for your perceptive input.
I have been evaluating audio equipment over the last 50 years. However, at my age now, I would not consider myself the best listener. I suspect that many of my contemporaries, like John Atkinson are in the same boat.
The best I can do today, is to 'live' with something and note a departure from what I heard before. I use others to do my 'reviewing' for me.
However, that does NOT mean that I was always this way. 35 years ago, I evaluated the 5534 and found it 'wanting' in a tight A-B test.
The same year, I also found that I could NOT hear the difference between a Levinson JC-2 line stage and a Dyna PAS3X (a preamp I used for 10 years before the JC-2, in a typical ABX test, with a typical ABX box. Some of my contemporaries gave up audio electronic design at this point. I went on, instead, and made dozens of products, each 'better' than the last.
The last time I did some SERIOUS evaluation was about 20 years ago, when I had to put my hi fi back together, after what I had was destroyed in a firestorm.
I tried cheap cables, at first. Not anymore.
I tried a different turntable and cartridge type. Not anymore
I tried similar speakers to what I had before. Got rid of those, too!
Today I am settled with what I have, with few inclinations to upgrade. I just can't hear that much difference, anymore.
However, I am not going out of my way to subject myself or my personal audio equipment to any 'extra' testing, just because people don't believe what I say about audio quality. I hope this settles the problem.
Now, back to a simple 1 dual IC line amp. That should be good enough for the majority of my critics out there. Don't you think?
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Old 6th December 2012, 08:12 AM   #30909
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Quote:
Originally Posted by Esperado View Post
Zillion slew rate current feedback everywhere you can, including Power amps, spherical horns with good drivers (i Know only one), two ways (time aligned) in your enclosures (with added sub if you like), high efficiency, comfortable margins of power, digital active filters with flatten response curve and group delay alignment of your speakers is the way i suggest, with the necessary acoustic treatment of the listening room:-)
Did-we agree on that ?.
Nope, disagree ...

Getting the many technical things right as you have, may, or may not, tip the balance over to that 100%. Some people are lucky enough to fluke it at times, others not ...

The headache is, that getting good sound is subtractive, not additive. And I've talked of this concept elsewhere, as some may be aware ...

Which means, that good sound is not adding good source to good amps to good speakers to good room. It may work, but no guarantees. Rather, any system is capable of excellent sound but a weakness, a problem, an issue somewhere subtracts from that excellence. And so the process I use is to track down, unearth that problem child, and counter, subtract that. The chances are almost zero that I will have good sound at this point, because there are bound to be more weaknesses, so now I have to locate the next issue and resolve that. And on and on it goes ...

Think of it like this: a space capsule that leaks air, anywhere, is useless, the people inside will die. So the trick is to remove every single leak, no matter how minor. Making the walls thicker, using higher quality rubber for the seals, applying special sealant over everything you can see, is not going to help if some tiny valve somewhere is playing up. No matter what I do elsewhere, until I realise I have this valve problem and fix it the people inside the capsule are doomed ...

This is the approach I use for improving audio, and it has served me well ...

Frank
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Old 6th December 2012, 08:57 AM   #30910
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Originally Posted by Jay View Post
We need preamp because we need to boost details/dynamics that is not available with straight wire.
This sentence is revealing !!!!!
How-do-you do that ? Do you have an expander in your preamp ? With a "detail" discriminator ?

I need a preamp to can tune the levels, switch and distribute sources WITHOUT deteriorating anything. Like "boosting" i don't know what. Enclosures witch dont boost any frequency ranges and don't add resonances (impossible).
Quote:
Originally Posted by fas42 View Post
The headache is, that getting good sound is subtractive, not additive.
Of course, each component adds its own distortion, noise, phase turns, bandwidth limitation, lack of linearities.
So subtract something from the original signal. It is no more complicated than this, but it seems obvious that, for you, It is a sort of "cooking", playing with tastes and flavors...
I hate to say that, because you are sympathetic, but, for me, both of you have a middle-aged and surrealistic kind of position.
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Last edited by Esperado; 6th December 2012 at 09:12 AM.
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