mountainhick
Tele-Meister
The preamp is unaltered 6G6B bassman. (I may play with tone, coupling and cathode values depending on what I get from the stock design after trying it)
The power section is a take off from the "Littlerock", 2 6AK6 in parallel.
Questions:
Connecting preamp to power amp- What to do for each of these:
1-The 470K resistor is from the 6G6B, a mixing resistor that had a partner from the "normal" preamp channel. I am only using the bass channel. Grid stoppers are added for the power tubes, I am assuming as demixers to isolate grids*. Are all of these necessary?
*(the Littlerock designer extolled the virtues of the power tubes not being coupled so it is more tolerant of non matched tubes)
2- Coupling cap following the 470K is
- .0005uf on one PI grid, 0.1uf on the other on the Bassman,
- .022uf on the Littlerock
Seems .022 is a reasonable choice, but I am not certain.
3-(Side question, is the imbalance for the bassman PI to create more wave asymmetry for harmonics??)
Cathode values:
4-standard values for single ended, single tube 6AK6 is 560 ohm, and 22uf cap. The Littlerock designer used 510ohm and 100uf. Am I correct that this will allow more bass? Perhaps get muddy?
5-The grid leak resistor covers both power tubes. It is 220K for the Littlerock. In other SE single tube designs this value varies from a 1meg volume pot to a 1meg pot followed by 260K, to 470 ohm, all to ground, and some are bypassed with a cap. I don't understand the possible trade offs here. Can someone fill me in?
EDIT: Screen resistors are 1K
The power section is a take off from the "Littlerock", 2 6AK6 in parallel.
Questions:
Connecting preamp to power amp- What to do for each of these:
1-The 470K resistor is from the 6G6B, a mixing resistor that had a partner from the "normal" preamp channel. I am only using the bass channel. Grid stoppers are added for the power tubes, I am assuming as demixers to isolate grids*. Are all of these necessary?
*(the Littlerock designer extolled the virtues of the power tubes not being coupled so it is more tolerant of non matched tubes)
2- Coupling cap following the 470K is
- .0005uf on one PI grid, 0.1uf on the other on the Bassman,
- .022uf on the Littlerock
Seems .022 is a reasonable choice, but I am not certain.
3-(Side question, is the imbalance for the bassman PI to create more wave asymmetry for harmonics??)
Cathode values:
4-standard values for single ended, single tube 6AK6 is 560 ohm, and 22uf cap. The Littlerock designer used 510ohm and 100uf. Am I correct that this will allow more bass? Perhaps get muddy?
5-The grid leak resistor covers both power tubes. It is 220K for the Littlerock. In other SE single tube designs this value varies from a 1meg volume pot to a 1meg pot followed by 260K, to 470 ohm, all to ground, and some are bypassed with a cap. I don't understand the possible trade offs here. Can someone fill me in?
EDIT: Screen resistors are 1K
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