I'm Roberto from Italy
I built TRANSCENDENT OTL THE 80 WATT VERSION book by Mr. Bruce Audio Reality.
I have a problem of crossover distortion that starts from 10KHz up.
I adjusted the bias to get about 10mV output with no input signal.
On the upper-39V.
On the lower-194V.

Signal: 18KHz
Oscilloscope: div 0,5v - x10 probe
Load: 8 Ohms.
Where can I take action to reduce the distortion?
Thank you.
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Bruce Rozenblit
You can't get rid of it.  My technology has improved considerably since 1996.  Fortunately, the  power requirements above 10 kHz are tiny and the notch wont be audible at these low power, very high frequencies.  One of the hard lessons I learned when I started in this business is which characteristics are dominant and which are not.  This one isn't.  Your amp will sound great as is.       //
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Thank you mr. Bruce.
Sometimes they are too picky.
Listening to music with OTL for about a year with 4 valves per channel, now I put 8 tubes per channel.
The sound is wonderful, especially the midrange.
I am passionate about technology OTL, over the years I have built several, but yours is one of the best.
Thank you again mr. Bruce.
In the photos:
OTL 25W with 6080
OTL 25W with 6C33C
OTL 60W with 6C33C
OTL 25W with EL509-2
OTL 80W with EL509-2 project Bruce Rozenblit
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