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I've got a ~1949 Thordarson PA amp that's been on the back burner for a while, waiting to be rebuilt as a small guitar amp. Its original configuration was two pentodes into a single 6L6.
I've been thinking of trying one pentode (6J7 or 6SJ7) gain stage and one triode (6SQ7) gain stage, but I'm wondering about the relative merits of each and, specifically, about which to use as the input stage. I like the idea that pentodes don't have the Miller capacitance issues that triodes do, but, on the other hand, I know that they tend to be noisier. Then, there are the different distortion characteristics.
This will be built as a head, not as a combo, so, hopefully, microphonics won't be as much of a problem as they are in combos.
I know this is a fairly general question, and I'm just looking for general impressions of what has tended to work well for builders in terms of where to use triodes and where to use pentodes.
I've been thinking of trying one pentode (6J7 or 6SJ7) gain stage and one triode (6SQ7) gain stage, but I'm wondering about the relative merits of each and, specifically, about which to use as the input stage. I like the idea that pentodes don't have the Miller capacitance issues that triodes do, but, on the other hand, I know that they tend to be noisier. Then, there are the different distortion characteristics.
This will be built as a head, not as a combo, so, hopefully, microphonics won't be as much of a problem as they are in combos.
I know this is a fairly general question, and I'm just looking for general impressions of what has tended to work well for builders in terms of where to use triodes and where to use pentodes.