Hi forum members,
Is it possible to use 2 different pairs of power tubes in a 100 Watter with one OT?
Technically you have to put 2 different bias units in the amp and that's it?
For 2 KT66 and 2 EL34 would be the 1202-84 with 4kOhms or the 1202-132 with 1.75kOhms?
I think the issue with the different loads is the only concern ?
Any thought on this?
Cheers
Dom
2 different tube pairs into one OT ?
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Re: 2 different tube pairs into one OT ?
Mixing EL34's with 6550's or KT88's doesn't have any other issues apart from bias currents (as long as you lower the bias splitters for 6550's/KT88's), but mixing EL34's with KT66's doesn't seem such a good idea since they will mismatch impedance-wise. Personally if I were going to mix EL34's with KT66's I'd only consider it with two OT's, early JTM45/100 style. But then, that really limits the amp for flexibility.
So I like purple, okay!!!!!!
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Re: 2 different tube pairs into one OT ?
no problem IF you bias. you probably have to build two bias circuits. both the 1k7 and the 4k load should work with the standard tubes
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Super 100 amps: 1202-119 & 1202-84
JTM45 RS OT JTM50 JMP50 1959/2203/34/39
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Super 100 amps: 1202-119 & 1202-84
JTM45 RS OT JTM50 JMP50 1959/2203/34/39
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Re: 2 different tube pairs into one OT ?
Yes it will work, but won't one pair be working harder than the other because of the different loads? Can't quite figure it out.Roe wrote:no problem IF you bias. you probably have to build two bias circuits. both the 1k7 and the 4k load should work with the standard tubes
So I like purple, okay!!!!!!
83.7% of all statistics are made up on the spot!
83.7% of all statistics are made up on the spot!