So you won't even click a link until I drive a bentley for 6 months, yet you were the one who asked for an example of state of the art in audio? Curious.
BTW if you look up fine art you will notice that your Bentley doesn't make it by dint of it having some usable function. The difference between your car and the Phaeton it is based on is CRAFTSMANSHIP.
BTW if you look up fine art you will notice that your Bentley doesn't make it by dint of it having some usable function. The difference between your car and the Phaeton it is based on is CRAFTSMANSHIP.
I think you mean 4K Blu-ray player? For a professional Engineer,lecturer and inventor you seem quite confused a lot of the time.
Hoola Hoola Hoola, Boola Boola Boola, Moola-Moola Mula.
Bankers !
https://www.youtube.com/watch?v=X_r-fur3Zr0
(is your nose itching, or are you happy to see me ?)
And of course the obvious question: How much moola for the mola mola?
[edit:] Oh that's a Bruno effort! (having just clicked on the link). It's probably quite excellent.
[second edit:] The specs for the phono stage are interesting, with voltage noise spectral density listed for the MC input, and current noise for the MM. Curious. I like the notion that they are two independent channels. 900fA/sq rt Hz however is not really all that low, corresponding to thermal noise of a ~20k resistor at 300K.
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Base model is over Thailand rate.
(happy to see me, thought so. https://www.youtube.com/watch?v=Apjvf9YNzEM )
(happy to see me, thought so. https://www.youtube.com/watch?v=Apjvf9YNzEM )
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Damir, I think on your VFA you could trade some of the higher LG at LF for lower overall LG at HF using TPC or TMC. You could conceivably then end up with the wide loop gain bandwidth you are demonstrating in your CFA.
I did a lot of sims on this and wrote up an article on my findings. When you increase the loop gain on CFA's, you do have to consider the compensation design of course, so these high loop gain CFA's end up having the same issues do deal with as high loop gain VFA's.
What I also notice is the ULG has gone up significantly on a lot of designs to 3MHz+ over the last few years as designers have gotten more confident in dealing with the associated compensation and layout issues. This clearly is possible because of the use of mosfet output stage, or the use of high Ft transistors. All this helps course to increase the LG at lower frequencies, and hence decrease distortion.
I have to also comment here that although the designs presented have outstanding performance, they are very complex. I am seeing 30+ active devices and in some cases nearer 40. I must confess, personally I am headed in the opposite direction in terms of my design philosophy - I'll happily accept 0.1% THD at 20 kHz as long as its low order. With regard to bandwidth and rise/fall time, I think CFA makes this very easy to achieve.
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sent by a friend as an example
Once, because the professor had one and thought it was respectable, I had to put one of these kits together and install it to provide music for planetarium shows at UCLA. I tried to persuade him that there were better amplifiers, to no avail.
A blast from the past. Six transistors per channel, not counting the power supply.D
I have to also comment here that although the designs presented have outstanding performance, they are very complex. I am seeing 30+ active devices and in some cases nearer 40. I must confess, personally I am headed in the opposite direction in terms of my design philosophy - I'll happily accept 0.1% THD at 20 kHz as long as its low order. With regard to bandwidth and rise/fall time, I think CFA makes this very easy to achieve.
Once, because the professor had one and thought it was respectable, I had to put one of these kits together and install it to provide music for planetarium shows at UCLA. I tried to persuade him that there were better amplifiers, to no avail.
Circa 1970 we built from kit and installed MkIII's in all the projection booths at MIT. Unfortunately they did not have a 70V output option. BTW were there better 70V transformers I don't recall?
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Difficult loads blew them up too.
At nearly curtain time at a concert in Schoenberg Hall, a borrowed Stereo 120 driving the cantankerous Oscar Staffsud Sr.'s loudspeakers failed. The concert relied heavily on recorded music, mostly from tape pieces.
I ran across campus to the considerably-remote electronic music studio and hand-carried a Mackintosh MC275 back to the concert and got it hooked up just in the nick of time. If I'd had to do that today I would have a certain coronary.
I then repaired the 120 and returned it to the owner. He proceeded to blow it up again, and of course speculated that my repair had "weakened it", and that he should have paid heed to yet another professor who advised against loaning anything to the department. From what I could tell, he had shorted out the speaker connections to the chassis, and protested that after all they were only teeny little strands of wire.
I fixed it again but not until we had a huge fight when he called me and expressed impatience. I was about to quit that job anyway. Remarkably, we are now distant friends but quite cordial. It took another professor to take me to task for being about 20 minutes late on a Saturday, for a electronic music studio mixdown of his tape piece, to catalyze the resignation. That professor was chronically late for everything. In his case years later I severed relations completely, after a final transgression.
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Don't you love the rhetoric about the comparison of the 120 to the pretty-decent Dynaco tube amp?
However, I do appreciate a review that includes a schematic
I would like to tell an experience that happened in 1965 at a hi fi show. I was still a student, just finishing my senior year, and my musician friend and I went to see the show. He had golden ears as I did, so we went around the exhibits evaluating the sound quality. The best 'solid state' exhibit was JBL and it sounded fairly lousy. The best quality exhibit was a Marantz 9 in triode mode, that we did NOT know what it was until we asked the exhibitor. Gee, even today, I would think the same thing.
The Dyna exhibit had some solid state offerings, and I talked to one of their engineers, saying that I had Dyna MK3's and a PAS3 preamp. They were open enough to actually tell us to keep the tube equipment, quite a surprise. IF you can live with solid state of the early Dyna quality, you might as well drive a Yugo of the past as well, because Honda and above is beyond your appreciation as well. '-)
The Dyna exhibit had some solid state offerings, and I talked to one of their engineers, saying that I had Dyna MK3's and a PAS3 preamp. They were open enough to actually tell us to keep the tube equipment, quite a surprise. IF you can live with solid state of the early Dyna quality, you might as well drive a Yugo of the past as well, because Honda and above is beyond your appreciation as well. '-)
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