Valve amp bias question

Discussion in 'Hi-Fi and General Audio' started by Davidcat, Oct 2, 2017.

  1. Davidcat

    Davidcat

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    Hi guys,
    After many years of using class A solid state power amps, I have finally taken the plunge and got myself a valve amp. I have used valve pre amps on and off over the years but this is my first biggie. It's a JJ Electronics jj322 300b model. I bought it online from a store as an ex-display item, it looks to have had quite some use , not a problem as it was at a knock down price.
    My question is this, how do I check the bias? I can't see any measuring points or trim pots. I don't think it's auto bias, although I might be wrong. Any ideas?
    It does sound pretty good but I'm worried because it's used and I had to replace one 300b that was broken in transit (the seller sent a new one). Thanks in advance for any info.
     
    Davidcat, Oct 2, 2017
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  2. Davidcat

    Roxbrough

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    "It does sound pretty good".

    Then don't worry or fiddle.
     
    Roxbrough, Oct 3, 2017
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  3. Davidcat

    Davidcat

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    Well, yeah, that's a help, but it's gonna need adjusting sometime, right?
     
    Davidcat, Oct 3, 2017
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