I am pretty sure that you have seen these already. Approximately 2 years ago, I extracted important bits from a few sources and created one jpg file. Have a look and see if you can find something useful.
There's also Nelson's paper on the current gain in Alephs... but I am pretty sure you've seen that one already.
Hi Extreme_Boky,
thank you for caring....!
Yes, I know these articles and I can determine the 50% contribution of the upper IRFP. It did it the last years already some times.
My interest was this time to chase the neg phase H2, even when the 50% rule is injured.
Nelson spoke in connection with the Aleph amps not about the aim to get H2 neg phase, hope I am right.
But maybe the 50% contribution rule may include normally the neg phase H2.
But unfortunately not in my case.....not yet.
:--))
I just put again two quadruples of IRFP together and will make a new try.
thank you for caring....!
Yes, I know these articles and I can determine the 50% contribution of the upper IRFP. It did it the last years already some times.
My interest was this time to chase the neg phase H2, even when the 50% rule is injured.
Nelson spoke in connection with the Aleph amps not about the aim to get H2 neg phase, hope I am right.
But maybe the 50% contribution rule may include normally the neg phase H2.
But unfortunately not in my case.....not yet.
:--))
I just put again two quadruples of IRFP together and will make a new try.
Which resistor(s) # should I be measuring AC? 11 and/or 12 on lower rail, 9 and/or 10 on upper rail? Sorry, not so hot on following solid state schematics, tube schematics are a different story.
No insulator needed between rectifier and base plate. I don't use heat sink compound on my rectifiers and have had no problems. I just carefully checked the temperature of a rectifier that was passing 2.5A at about 38V and it was barely warm to my touch. The bridge rectifiers that I use are 35A 600V.
Meanwhile I have strong doubts if my way to determine the H2 neg Phase with my sound card an Diana works as intended......
So do not take my last posting serious, maybe the fault is not in handling but in hard- and software.
Maybe someone can repeat for me the correct way to see the H2 phase with REW? I know if shown +90° it should be negative, but if I remember correct, the was a posting that his 90° suffix + or - depends on the fact the amp is inverting or not. Correct?
And Jim (6l6) what did you use as hardware to see the residual in your oscilloscope?
So do not take my last posting serious, maybe the fault is not in handling but in hard- and software.
Maybe someone can repeat for me the correct way to see the H2 phase with REW? I know if shown +90° it should be negative, but if I remember correct, the was a posting that his 90° suffix + or - depends on the fact the amp is inverting or not. Correct?
And Jim (6l6) what did you use as hardware to see the residual in your oscilloscope?
I have compared the results from DiAna and REW, and positive phase H2 is -90 degrees in REW. This was done with an amplifier that I knew had positive phase H2.
As for inverting or not, REW does not know. It only looks at the amplifier's output and determines whether the distortion is in or out phase with respect to the fundamental signal.
I like listening to positive phase H2. Both my preamp and amplifiers output positive phase H2 so that is good. However I do have an preamp, the ACP+, which has negative phase H2, and when used with my positive phase amplifiers, result in negative phase H2 at the amplifier output. To overcome that, I would reverse the speaker leads.
So getting back to inverting or not, if an amplifier inverts phase, does that mean a positive phase H2 signal at input becomes a negative phase H2 at output? That would seem logical to me. But wait, that would be logical only if the inverting amplifier outputs positive phase H2 on its own.
As for inverting or not, REW does not know. It only looks at the amplifier's output and determines whether the distortion is in or out phase with respect to the fundamental signal.
I like listening to positive phase H2. Both my preamp and amplifiers output positive phase H2 so that is good. However I do have an preamp, the ACP+, which has negative phase H2, and when used with my positive phase amplifiers, result in negative phase H2 at the amplifier output. To overcome that, I would reverse the speaker leads.
So getting back to inverting or not, if an amplifier inverts phase, does that mean a positive phase H2 signal at input becomes a negative phase H2 at output? That would seem logical to me. But wait, that would be logical only if the inverting amplifier outputs positive phase H2 on its own.
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