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Re: Audible Differences: EL34 vs 6550 - yeah just a little!

Not too worried about it, really. I don't listen at earth shattering volume levels. The 6550's push the LSi9's at 4-ohm very, very well. The JoLida amps have both 4 and 8 ohm outputs.

Like I said in my e-mail to you, I am not sure how safe running the EL34's cool is (one would assume this would be perfectly fine), but I did listen at around 15mv for a few minutes and noticed some pleasing differences in the sound.

JoLida needs to get their ducks in a row when it comes to their people telling folks that the 502A will work with EL34's... apparently Mike Allen is wrong, according to a rep there, and the 502A/502B need a resistor change to properly bias for both 6550's and EL34's. Luckily, it's a very, very simple swap.

R14 and R15 need to be changed from 22k ohm to 13.3k/14k ohm for each channel. After this, I have been told, you will be able to bias for each type of tube.


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