Whos Got a Little Bastard?

[Ancient Mariner]

[quote name='umph' post='972608' date='Sep 30 2010, 12:52 PM']83's really aren't the ideal valve for the drive section in any amp, 81's do a much better job, 82's an even better one and 12bh7s / ecc99's even better than that![/quote]

83s are fine if the maker designs the amp correctly. It's not necessary (or even desirable) to make a valve produce all of its gain, and it can still be attenuated afterward to prevent distortion in the next stage. And multiple non-distorting stages can add a very pleasant compression.

Having said that, I like the tone of 12AU7s in some (guitar) amps, and the reduced overdrive doesn't do any harm at all.

[umph]

[quote name='Ancient Mariner' post='989161' date='Oct 15 2010, 01:29 PM']83s are fine if the maker designs the amp correctly. It's not necessary (or even desirable) to make a valve produce all of its gain, and it can still be attenuated afterward to prevent distortion in the next stage. And multiple non-distorting stages can add a very pleasant compression.

Having said that, I like the tone of 12AU7s in some (guitar) amps, and the reduced overdrive doesn't do any harm at all.[/quote]

83's do work but they're high gain rather than high current like the 82 which isn't ideal for driving valves cleanly up to their full power, saying that though 84's don't need a huge amount of grid current to get up to full voltage.

[Ancient Mariner]

[quote name='umph' post='989191' date='Oct 15 2010, 01:54 PM']83's do work but they're high gain rather than high current like the 82 which isn't ideal for driving valves cleanly up to their full power, saying that though 84's don't need a huge amount of grid current to get up to full voltage.[/quote]

Sure, if high current is what you need for your design, and as you say '84s need less to push them.

[bozzbass]

Do those of you cutting down the amount of overdrive by putting in lower gain preamp tubes notice any loss in volume?