Four thirds of Americans today struggle with fractions.That's too many percent. (just kidding)
I am approximately one of them.
Four thirds of Americans today struggle with fractions.That's too many percent. (just kidding)
Thanks guys! There is no magic circuit though. I once read something like this---the final sound quality is 50% design topology, 50% parts selection, and 50% layout and build quality. Meaning that these are all critical factors.
The earlier one uses 3 tubes (6072/12ay7) with a SRPP input stage and passive eq between the two stages.
I certainly have my biases, and I haven't built Sal's preamp, but I would be willing to wager that pentode wiring the D3A and directly coupling it to the 5687 would be a step toward making what I have thought for several years now would be the best possible tube phono preamp. These are pretty difficult challenges though!
The second preamp isn't too far from what I have in mind, but the 6J9P has about half the transconductance of the D3A (but they are otherwise quite similar).
More transconductance=less noise. You'll also get more gain as a pentode with more transconductance (assuming the plate load resistor stays the same).So how would that difference effect the design and/or sound?
More transconductance=less noise. You'll also get more gain as a pentode with more transconductance (assuming the plate load resistor stays the same).