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Old 4th October 2012, 03:44 PM   #27961
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These efforts to make 'World Class' reproduction cost time and money to make. It always surprises me that amateurs cannot assess where the money goes.
Of course, it is a different world entirely with mid fi. I know from recent experience that quality mid fi, has a cheap case, lots of plastic in the parts, like connectors, etc. Marginal capacitors, IC's, instead of tubes, jfets, or quality matched bipolar devices.
However, the ENGINEERING of mid fi can be every bit as good as anything we old fashioned analog engineers will ever do, but when it comes to absolute sound quality, they also find that we can 'improve' their products, by 'throwing money' at them. '-)
That is why there are so many product 'modifiers' out there who do a successful business, improving on the 'well engineered' but otherwise compromised production, products.

Last edited by john curl; 4th October 2012 at 04:02 PM.
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Old 4th October 2012, 04:00 PM   #27962
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You should try building something of that quality, sometime. It gets expensive.
Doing a first-rate job with tubes is nontrivial. The high perveance ones like the 6H30, 6C45 et al. are highly variable in their properties. The grid-cathode spacing is amazingly small. The mechanical Q of the grid structure is quite high, which is both good and bad news: good, as it is rarely excited acoustically, and bad, since when it is it rings for a long time.

So if one counts on even-order distortion reduction with balanced mode, matching is necessary and very labor-intensive. And to get the best performance it's well to lightly load the plates, and if you just don't want sand state devices to get near your signal matters get complicated. Since the piece under consideration uses tubes in the power supply I suspect they avoid almost all silicon.
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Old 4th October 2012, 04:10 PM   #27963
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Last night I saw a video program on the building of an F1 racing car. It sure was an expensive enterprise. I think it was $65 for just one lug nut, for example. Makes upper scale audio fabrication look like a bunch of cheapskates. '-)
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Old 4th October 2012, 04:20 PM   #27964
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True, John, true. And so far I have not had to seek corporate sponsorship for my audio.
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Old 4th October 2012, 07:27 PM   #27965
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In any case, that is what it takes to make 'World Class' components. Whether race cars or preamps. That is my experience. I can design 'Hondas' too, and do so, all the time, but they are not 'World Class', even if they can get an 'A' rating for best 'bang for the buck' much like a Honda often is rated.
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Old 4th October 2012, 07:28 PM   #27966
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True, John, true. And so far I have not had to seek corporate sponsorship for my audio.
And don't forget Colin Chapman's dictum that the optimum F1 car should fall apart on its victory lap. Far more important than capacitors hand carved from solid Unobtainium by virgins etc
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Old 4th October 2012, 07:38 PM   #27967
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Different problem, kgrlee. For autos, they are EXPENDABLE! One race, so long as you can finish it, is enough to design for. With caps, it is the difficulty in making the 'optimum' materials into something that is both reliable and without other faults. Teflon is an 'optimum' material that is hard to work with, very hard to work with, and this makes it expensive.
For example, major laboratories, for the last 50 years or so have 1uf Teflon caps in their parts stock. They might typically cost $100 each and cost about the same, 30 years ago. This is because they could RELY on this cap to behave and follow the ideal mathematical prediction of its performance, without adding extra garbage. In audio, we find Teflon to do the same thing.

Last edited by john curl; 4th October 2012 at 07:45 PM.
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Old 4th October 2012, 09:54 PM   #27968
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an expensive enterprise.
During each of the few times I've flown till now, someone tried to slam an overhead luggage compartment shut like this :
http://www.funny-potato.com/blog/wp-...ent-planes.gif

Back when I worked on that stuff for a short period, the doors were made of honeycomb and foam, covered with kevlar woven roving, with a plastic foil finish.
Super stiff, super light, cost a grand each.

Next time you hop a plane, realise you're taking a spin on an F1.
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Old 5th October 2012, 01:40 AM   #27969
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Different problem, kgrlee. For autos, they are EXPENDABLE! One race, so long as you can finish it, is enough to design for. ....
Another interpretation is that any measure to prevent the failure just past the finish line would have caused the winner to lose (added weight, or rigidiy etc).

Requires knowing your requirements and how they interplay really really well to achieve that optimized design.

Just my 2 cents
-Antonio
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Old 5th October 2012, 01:52 AM   #27970
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Another interpretation is that any measure to prevent the failure just past the finish line would have caused the winner to lose (added weight, or rigidiy etc).

Requires knowing your requirements and how they interplay really really well to achieve that optimized design.

Just my 2 cents
-Antonio
This reminds me of phase change heatsinking. Works great for missiles. You only need to deliver the payload. The survival of the semiconductors thereafter is of no consequence.

Yes, crazymaking, I agree.
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