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Old 17th August 2012, 06:18 PM   #26571
bcarso is offline bcarso  United States
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Originally Posted by scott wurcer View Post
Every time I travel in Europe I try to check out the audio magazines (the high end seems to be covered so much more there) and I see at least two or three or more "ultimate" phono stages, often the prices far outdo the CTC BT. Are there really that many fickle record collectors?

BTW Clark Gable's Deusenberg is on the block this week, estimate $10^7, Better tell your customers.
What surprises me about current "high-end" phono preamp offerings, in distinction I suspect to JC's past offerings, is how mediocre most are in noise performance, if we go by JA's measurements in Stereophile. Now he does not as yet attempt to terminate the inputs with loads representative of real cartridges, let alone do that and back out the parallel (i.e., "current") noise (he just measures the voltage noise). And no manufacturer that I know of provides parallel noise performance either. However (as you remarked somewhere), for MM cartridges one would want a JFET input, and among others the over-the-top Class A+ Boulder machine apparently still sticks to their spawn-of-Jensen 990 discrete opamps (Boulder does not reveal their phono performance).

Some of the preamps have actually been so bad that JA has complained, even when Fremer is going nuts over them.

The old National Semiconductor Audio Handbook is amusing about this issue of phono preamp noise performance. In the early part of the book, pushing one of their ICs for phono use, statements are made about noise performance. Then, in the back of the book, a detailed discussion and inventory of noise contributions basically refutes the claims made in the earlier part of the book!

Brad
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Old 17th August 2012, 06:32 PM   #26572
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Originally Posted by bcarso View Post
and among others the over-the-top Class A+ Boulder machine apparently still sticks to their spawn-of-Jensen 990 discrete opamps (Boulder does not reveal their phono performance).

Brad
$29,000 just for the phono and $36,000 for the rest! I hope there are no IC's in the signal path.
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Old 17th August 2012, 06:50 PM   #26573
bcarso is offline bcarso  United States
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$29,000 just for the phono and $36,000 for the rest! I hope there are no IC's in the signal path.
That reminds me of auditioning an all-JFET discrete buffer in the signal chain of a local high-end aficionado, the notion being that his and another's golden ears might to some extent sanction or reject material evidence of my design "philosophy" before I moved forward on additional designs for one of them. The system had a fancy CD transport and fancy DAC, the guy's latest favorite three-chassis tube line level preamp, my board, and on to a box which had equalization for the favorite loudspeakers of the day, and then some favorite power amp.

After expressing his concerns that my board might blow out the tweeters and thereby cost him thousands, we auditioned the system, and my board was adjudged undetectable, pretty much, to the guy's astonishment (as he hated solid state in general and was sure he could hear when it was present).

I didn't think it politic to point out that, aside from the electronics in the CD playback (accepted as a necessary evil, as repeated playing of the same LP would be out of the question), the loudspeaker EQ box was filled with IC opamps.
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Old 17th August 2012, 07:04 PM   #26574
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Look what I found in the Net. Ground lift helps to silence some interferences caused by ground loops.
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Old 17th August 2012, 07:12 PM   #26575
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The other thing is that music in the home is generally much more homogenous and direct than in a concert hall. Someone once remarked (I think it was Floyd Toole) that a concert hall is one giant comb filter, what with its myriad reflections. With most of our efforts to control dispersion and reflections in our rooms we are in fact going away more and more from the life sound 'picture'.

jan
I guess that's why MBL sounds so "realistic." - omni-directional.

Discrete surround sound helps too.
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Old 17th August 2012, 07:19 PM   #26576
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Line arrays and other planar speakers like electrostatics sound so realistically because of the same reason. Especially when the room is properly treated, so good records reveal reverberation of concert halls.
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Old 17th August 2012, 07:36 PM   #26577
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Indeed very interesting stuff, but also stuff that has been researched ad infinitum. Seemingly unrelated issues like this 'filling in' of sound, expectation bias, changes in remembered events with circumstances, or, even more weird, phantom limb perceptions, all come back to one significant point: the brain is a prediction machine. Say a word and it completes the sentence, so to speak.

For 'us', there's a difference between, say, a 'real' chair in front of us and a chair remembered from yesterday. For the brain, it's all 'inside your head'. For the brain, there is no difference between reality and what is made up, remembered or imagined inside it.
But because we insist on this imaginary (pun intended) difference we get mad when someone suggests we imagined something. On the contrary, in a very real sense it's ALL imagined

jan
Hi Jan,

Well, not all imagined Jan. LEARNED. And there is a whole lot that goes on with our hearing that is understood that not many people understand or talk about.

For instance when a person has hearing loss it causes compensatory changes in the auditory pathways to try to compensate. Often when people first experience hearing loss they develop increased sensitivity to some sounds that are not loud (misophonia). It happened to my mom who found the turn signal on our car really bothersome for about a year, but eventually re-habituated to the sound and till it wasn't a problem.

The ears and whole sensory system work extremely well. And just because it can be fooled, doesn't mean the differences people say they can hear aren't real. Though I agree that often people, like my audiophile dad, attribute every difference they hear to the equipment which is a mistake.

John
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Old 17th August 2012, 07:37 PM   #26578
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Line arrays and other planar speakers like electrostatics sound so realistically because of the same reason. Especially when the room is properly treated, so good records reveal reverberation of concert halls.
Oh good! cause I've just about finished my planar dipole line array.
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Old 17th August 2012, 07:42 PM   #26579
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Even when imagined something non-existing, we use experience of real sensory perception to construct the imagination.
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Old 17th August 2012, 07:44 PM   #26580
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Already some people think they are observing a contest between two different schools of thought, instead of what it actually is: an attempt to bring understanding to someone who currently does not understand. I and the others are simply trying to teach basic science/maths/engineering - this is first/second year stuff! Once people understand the maths, we can then argue about how useful it is. While they still don't understand it, we are still in teaching mode.
It appears to me that the problem exists because the measured data goes against thier listening perceptions. Until that is resolved to thier satisfaction, explaining FFT et al is a waste of time on them. Perceptions Are a person's reality. So, in affect you are denying thier reality... which will never be accepted by many. we need a new strategy. IMO.

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