|
OTL Asylum OTL, Output Transformerless Amplifier User Group. |
For Sale Ads |
Use this form to submit comments directly to the Asylum moderators for this forum. We're particularly interested in truly outstanding posts that might be added to our FAQs.You may also use this form to provide feedback or to call attention to messages that may be in violation of our content rules.
Original Message
In this particular case I have found that....
Posted by 6AS7_6SN7 on November 28, 2010 at 11:35:59:
Best performance corresponds to 6-13 dB feedback.
http://www.audioasylum.com/cgi/vt.mpl?f=tubediy&m=190082
This is my last project and I have recently added a top panel switch to select 9dB or 14 dB NFB.
Even though the amplifier is very natural with zero feedback too when using 14 dB setting the absolute performance is (believe me or not) undistinguishable from my OTL!
In my opinion high plate voltage, almost zero PS impedance and high bias current (i.e. true class A operation) allow tetrode amplifiers to match OTL triode performance.
Best Regards
Luca