John Curl's Blowtorch preamplifier part II

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I used to do a lot of work with cooled charge preamps. At one point I was reading a paper in which, observing the drain current, the low-temp JFET resolved single-electron capture and release trapping-center events, which could be tuned by the back gate voltage :eek: Now that was some pretty clean material.

That idea was used in a one-off SEM I was responsible to keep running for the chemistry people who looked at the molecules of burnt HE. Used LN for cooling.
(SEM=Scanning Electron Microscope; HE=High Explosives; LN = Liquid Nitrogen) -RNM
 
Well, another quiet moment.
Sometimes I find that audio design and the hope for even better audio performance to be limited by the general commercial opinion that there is nothing more to be done, except to make it cheaper and smaller. Most younger people today, seem to be addicted to their portable music, and computers, and that certainly is 'compromised'.
We had the same thing happen in the 1950's, when the first portable radios were made available to the general public. We could have music on the beach, as well as at home or in the car. The 'fidelity' was not the same, but it was enough.
One major factor that was different in the 1960's and 1970's was a great striving for audio excellence, especially to meet or beat the high standard of fidelity shown already by vacuum tube based Marantz, McIntosh, etc, the hi end of the 1950's.
We kept running into problems, even with discrete designs, when we compared our latest mastering recorders, etc with our earlier tube based designs. We didn't specifically know WHY we had problems with solid state. Usually, our static measurements with solid state were generally better and more stable than most vacuum tube designs, so what was going on? Even worse, some engineers were pushing for IC based designs, to save space, heat, and ultimately, cost, but all we had in those days, at any reasonable price, was the uA741 or its near equivalent. That is WHY we still relate 'improvements' in audio from the days of using the UA741, because that is a real, worst case, example of marginal audio design.
This is why, in the early 70's a number of 'engineers' started reaching for better audio designs, ones that sounded as good or better than the earlier vacuum tube designs, which we still had around to remind us of what 'quality audio' was.
Now, what about today? Research still goes on, but at a very subdued level, because the audio 'authorities' think that we are wasting our time, and just confusing the public with new 'improvements' or greater 'understanding' of what is wrong with the present audio.
For example, CD's. Some think that they are all that is necessary. Not, in my listening opinion, SACD and even DVD 24/96 runs rings around CD. NOW, I have access to a really good digital player, and the differences are even MORE apparent.
 
In the 80's I thought digital would continue its push toward excellence for the masses. When I first heard SACD it thought it would swell and take over as THE format for the new century. It didn't work out that way. I have a saying "Untill Sam the Sham and the Pharoahs are on SACD then that format is a niche market". The best tubes and JFETS are not made any more. SACD is an orphan format. The best electrolytic caps are not made any more. Mediocrity eclipsed the push toward highest fidelity. Kinda' sucks huh?
 
Most younger people today, seem to be addicted to their portable music, and computers, and that certainly is 'compromised'.
John,
In general, they are not interested in quality playback. Period. There's nothing we can do.
They have other toys, other interests and their lives are totally different from our's. They, in their 20's, ARE the buying public and industry follows them. It is easier to get them interested in latest generation iPhone than in decent playback system. Sad, isn't it?

For example, CD's. Some think that they are all that is necessary. Not, in my listening opinion, SACD and even DVD 24/96 runs rings around CD. NOW, I have access to a really good digital player, and the differences are even MORE apparent.

I hope, you're comparing decent CD player to your SACD/DVD, not some sub $200 one from the recent production. I had the opportunity to evaluate Esoteric (Teac) X-01 D2 flagship SACD/CD machine for a week and it was a dissapointment (for me) compared to REALLY GOOD hot-rodded multibit CD player.
 
I don't mind that SACD is a 'niche market'. It is just like Blue Ray video. IT is really better, but the cost is yet too much for most people.
What I am impressed with is that I can actually get some first class sound with a really good SACD playback that, at least, compares with the best analog master tapes or vinyl playback. What I am also impressed with is WHEN you get a good enough playback equipment, the differences between CD and SACD become much more apparent, making the effort seem worthwhile.
We have ALWAYS had the chicken-egg argument with audio. The component playback designers saying that the sources are typically lousy, so why bother? And the recording engineers saying that the playback systems for the masses are so lousy, why bother? That is WHY hi end audio has ALWAYS been a 'niche market'.
 
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IMediocrity eclipsed the push toward highest fidelity. Kinda' sucks huh?

That's too strong I think. There is a difference between the quality of the majority of 'good systems' and the very best, but it's not so large as to warrant the term 'mediocrity'. Second best, maybe, but still very, very good.

And then you enter the area of diminishing returns. If the last incremental improvement can only be perceived/appreciated by a small fraction of the population, and also is relatively expensive, you know you'll never sell to the masses. That's a choice John and his peers must make. Doesn't mean that other choices are worse or better, just different.

People here like to Bose-bash but it stands to reason that Bose products have made more people happy than, say, all the Blowtorches in the world. Still, I'd very much like to own a BT.

jan
 
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People here like to Bose-bash but it stands to reason that Bose products have made more people happy than, say, all the Blowtorches in the world. ;)

jan
Owing primarily to the marketing that sold them in the first place, and the (relative) convenience of the products. My elderly friend Tupper loved the CD player powered speaker box as he had nothing to hook up or worry about. Amusingly, his wife, who, for the most part, never listened to music other than by accident, bought Tupp a multidisk accessory docking unit, and I tried to hook it up for them after their own efforts were unsuccessful. It was very poorly engineered from an ergonomic standpoint, and was prone to being misconnected and even damaged! I had to call the Bose help line, and we finally sorted it out!

And then it turned out that Tupp didn't often listen to more than one CD at a time anyway, and never used it.

After Harriet passed, and his own health deteriorated, Tupp went to a managed-care place, and I bought him a TEAC CD player with a headphone output and a pair of the Grado budget headphones. I auditioned the pairing for a few days, got a schematic, and popped the hood. Not really all that bad for a total investment of about 200 US. It would be interesting to know who designed the player.
 
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It seems pretty clear that digitalization of the signal from as soon as possible to as late as possible to get back to analog is what has been occuring for a long time now. Soon we will only have a microphone and a speaker that are still analog in nature.
Microsoft said a few years ago that the future was in mobility (portable) and everything available everywhere. No room there for discrete transistors/circuits anymore. Nor for much CE analog, either. -RNM
[funny though - transistors replaced tubes for their portability/small size also]
 
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