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Hello, I recently just built an amplifier with an ef86 in front followed by a long-tail PI(12ax7) into a quad of 6v6's. the 6v6's are JJ"s and are biased at 12w each. The speaker is a v30.
Now when I crank the amp it should be quite loud but it isn't. I can have a conversation over the amp and hear every word.
This is my first time building with an ef86, so it very well could be something incorrect with the tube or wiring. It's got the typical 220k Rp, 1M Rs, 2.2k Rk, 25uf Ck found in many spec books.
ef86>volume>PI>power amp
I will reply when I get home and have my voltages but thought I would ask in case something obvious jumps out to anyone. I do know I am running close to 450v on the plates of the 6v6's and I believe pin 6 on the ef86 is right around 120v. Pin 1(screen) is a few volts higher. The plates on the PI are around 300v. Cathode around 50v. The plate voltage seems quite high but not sure that would be causing it.
Any suggestions on what to check? The 6v6's are a matched quad and I purchased the ef86 at the same time. Thanks for your help.
Now when I crank the amp it should be quite loud but it isn't. I can have a conversation over the amp and hear every word.
This is my first time building with an ef86, so it very well could be something incorrect with the tube or wiring. It's got the typical 220k Rp, 1M Rs, 2.2k Rk, 25uf Ck found in many spec books.
ef86>volume>PI>power amp
I will reply when I get home and have my voltages but thought I would ask in case something obvious jumps out to anyone. I do know I am running close to 450v on the plates of the 6v6's and I believe pin 6 on the ef86 is right around 120v. Pin 1(screen) is a few volts higher. The plates on the PI are around 300v. Cathode around 50v. The plate voltage seems quite high but not sure that would be causing it.
Any suggestions on what to check? The 6v6's are a matched quad and I purchased the ef86 at the same time. Thanks for your help.
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