Sorry, but there's no evidence that any two reasonably well designed mint tins sound any different. 😀
se
How about a photocell on the top of the case that charges an ultracap, that supplies the led? Now, THAT is engineering!
Nah. The ultracaps have too high an ESR. The light doesn't look as good compared to being supplied from a good low impedance power supply.
Oh, and a photocell won't charge anything.
se
I mentioned it several times in this thread.
http://www.diyaudio.com/forums/anal...rch-preamplifier-part-ii-764.html#post2403966
That is a managable problem (the details would escape most here). One of the issues is double epi and engineering in the low noise in the first place. These processes were optimized for speed (in hindsight, blindly), TI gave a paper at this ISSCC on an SOI JFET amp with 8nV at 10Hz. We are on it (I am just a vociferous fly on the wall for this project), keep tuned. The geometries have shrunk to the point that the area is not an issue. The 743/45 was a big risk experiment, the fact that GE ran a whole generation of CAT scanners based on it, saved it. I'm not sure if I could get away with a sub 3nV FET amp in this market again.
In fact the AD745 is my own personal IC Blowtorch, probably a reasonable portion of them ended up as RIAA's.
Well, we've got measurements of an interconnect with a copper clad steel core which actually has signal flowing through it rather than something that's just in the vicinity.
No distortion there. At least nothing that can be seen above -145dB.
se
But the light doesn't look as good as it does when it's powered from a low impedance power supply.
Try it yourself.
se
Darn, can't even engineer something without people putting out lies and mis-information, such as low Z driving an LED. '-) This doesn't work, folks.
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Well, suggesting charging a capacitor with one of these doesn't inspire much confidence. 😛
se
Sorry everyone, I should have said PHOTOVOLTIC, rather than PHOTO (cell) in my original phrasing. I don't want to mislead anyone here, just convey a new idea. Gotcha, is a Steve Eddy trademark.
Okidoki, how about this :
http://www2.dupont.com/Photovoltaics/en_US/assets/images/planetsolar/planetsolar_1.jpg
(for joyriding, better steal the one in the top right corner : +45mph Italian aluminum boat, called Adler)
No, because bipolars and FETs are all transistors. A photocell and a photovoltaic are two different animals.
se
Moving on, I hope, to a more appropriate input.
I would like to talk, once more, about 2 stage phono design vs single or 1 stage phono design.
We have discussed the 1 stage phono design in some detail, some months ago. It can be made very cheaply, and was the design standard from many decades. Marantz, Mac, and Dyna phono stages in the '50's and the '60's, used this approach. Later, the Audio Research and the Mark Levinson JC-2 also used this approach, in the 1970's.
However, by 1980, many other phono designers started to use 2 stage design. This included: Electrocompaniet, the JC-80, Vendetta Research, and certainly many others.
In most cases, the 2 stage approach, whether made with vacuum tubes, solid state discrete, or IC's, tend to sound better, all else being equal.
You will find a tube design here, on this website, by SY, an excellent example of this design technique. Perhaps if you reviewed his preamp and the write-up around it, you would gather most of what you need to know about the 2 stage approach. (More later, if possible.)
I would like to talk, once more, about 2 stage phono design vs single or 1 stage phono design.
We have discussed the 1 stage phono design in some detail, some months ago. It can be made very cheaply, and was the design standard from many decades. Marantz, Mac, and Dyna phono stages in the '50's and the '60's, used this approach. Later, the Audio Research and the Mark Levinson JC-2 also used this approach, in the 1970's.
However, by 1980, many other phono designers started to use 2 stage design. This included: Electrocompaniet, the JC-80, Vendetta Research, and certainly many others.
In most cases, the 2 stage approach, whether made with vacuum tubes, solid state discrete, or IC's, tend to sound better, all else being equal.
You will find a tube design here, on this website, by SY, an excellent example of this design technique. Perhaps if you reviewed his preamp and the write-up around it, you would gather most of what you need to know about the 2 stage approach. (More later, if possible.)
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