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KT66s in place of KT88 tubes

I expect there will be a change in bias, and a reduction in power. But on the basis that lower power tubes generally produce more faithful sound, can one put KT66 tubes in an amp usually requiring two KT88s per channel? I'm thinking about a pair of Quad II/forty push-pull monoblocks.

dogberry

Showing 1 response by oddiofyl

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oddiofyl
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Some manual bias amps have enough range on the bias pot that they can use KT88 and KT66.  A good example is an amp like the Quicksilver Mid Mono it can use EL34, KT - 66 , 77, 88,  6l6 and a few other EL 34  / 6L6 variants.   

Always check with manufacturer!    Early versions can only use KT88.   New versions can use KT120 & KT 150 ,  running changes over the years allow for this. 

The newer version has more robust transformers, and other slight running changes  Perfect example of how you can damage your amp if you don't use the tube it shipped with or was compatible with at time of build. 

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