Lumba Ogir said:
I hope to start experimenting with this soon. The stability problems you point are there, and as you said they get worse with cascoding. I hope to do some experiments on a real loudspeaker because i fear that some spice simulations i have done are getting too far from reality.
Anyways the baseline model without cascoding simulates very, very good, the best part of it is that distortion keeps identical in both quantity and frequency over the audible spectrum, and this is very important for the subjective perception of the sound (the ear can "ignore" distortion if it's constant).
i will post experimental results when i get them. BTW i have started another thread about nonlinear capacitances and compensation because i did some elementary 3-lines calculations and found the results to be very, very, very promising.
To Hugh: I sent you an email from another account, did you receive it?
Mine did not oscilate with my loudspeakers, cables, and with a zobel network with the ccs biased at medium current. Did you try it and found any problems?
Hugh: I have resent the mail one more time, if you don't receive it you should perhaps recheck there is nothing that could block it in your computer.
Hugh: I have resent the mail one more time, if you don't receive it you should perhaps recheck there is nothing that could block it in your computer.
ionomolo,
the driver decisively determines the properties of the output stage, a great feature of the CFP. In the first place, it should have outstanding abilities for voltage amplification (as 100% feedback used the stage is an emitter follower with low output impedance). I have got 600pF input capacitances and certainly would not be happy with 5mA driving current causing distortions. It needs probably to deliver some current to the load at high frequencies as well. Not sure about the gain, trying to find a suitable type to get this right.
the driver decisively determines the properties of the output stage, a great feature of the CFP. In the first place, it should have outstanding abilities for voltage amplification (as 100% feedback used the stage is an emitter follower with low output impedance). I have got 600pF input capacitances and certainly would not be happy with 5mA driving current causing distortions. It needs probably to deliver some current to the load at high frequencies as well. Not sure about the gain, trying to find a suitable type to get this right.
Lumba Ogir said:ionomolo,
welcome back to the arena.
Did you make or skip your examen?
Fifty-fifty, it seems that it will keep me worried until i know how it went.
I hope to order all the parts soon and build a prototype, with my tube "isa" slot:
http://www.diyaudio.com/forums/showthread.php?s=&postid=1550385#post1550385
I will try an Aikido to drive it.EDIT:
http://www.tubecad.com/2007/06/blog0111.htm
Look, they seem to have just taken my idea... well the idea that Hugh had 10 years ago. This will come up to be the most independently-rediscovered thing ever.
Hugh, is there any other way to contact you? I have already sent 10 emails from three different accounts both using smtp and webmail and they seem not to arrive. I have a couple more things to discuss with you. Perhaps you could send me a link to another contact adress. The pm function in the forum also does not work.
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