How bad is it to be 100% off on your OT primary.
Im building a BF Fendery amp with reverb and my OT isnt quite what I was lead to believe it turns out that it is 2.5K rather than 5K at 4,8,16.
How bad will it be for the tubes/sound to run them at 2.5K rather than 5K
6L6's, 450V on the plates 400 on the screens
Mismatch on the OT
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JazzGuitarGimp
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Re: Mismatch on the OT
If you just re-label your output taps as 8, 16, and 32, you'll have a 5K load on the output tubes.
Lou Rossi Designs
Printed Circuit Design & Layout,
and Schematic Capture
Printed Circuit Design & Layout,
and Schematic Capture
Re: Mismatch on the OT
there in lies the problem i nee 4ohms
Re: Mismatch on the OT
There's the long standing practice of using extension cabs with Fender combos, which will have the same effect, without reports of it being a problem or sounding bad.
The power output may be reduced a little, and the 6L6 plate dissipation may increase a little.
Pete
The power output may be reduced a little, and the 6L6 plate dissipation may increase a little.
How are you achieving that screen voltage?6L6's, 450V on the plates 400 on the screens
Pete
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Re: Mismatch on the OT
Typically safer to run 100% higher than 100% lower I think. So an 8 into a 4 would decrease your load line towards higher voltage swing, away from higher current swing.
Running a 4 into an 8 would push your load line in the direction of higher current swing. Since you're only at 450V you are probably totally safe, so long as you're not biased super hot. Like pdf64 says, your power output will not be maximum
Running a 4 into an 8 would push your load line in the direction of higher current swing. Since you're only at 450V you are probably totally safe, so long as you're not biased super hot. Like pdf64 says, your power output will not be maximum