In Reply to: RE: 6SL7 posted by GeorgePope on March 20, 2017 at 01:36:42:
The simple answer is : there are NO pin alternatives to the 2A3 pin arrangement.
The two-stage DC circuit's primary gain is from the driver, where driver choice and implementation is most urgent when seeking perfection.
My entire response addresses, and is entitled " 6SL7" and all pin comments were referring to an octal socket's pins. That would be the 6SL7, where alternative better choices exist.
As examples of three "non-octals", with linear graphs and mu of 100 : 1/2 12AX7 as a 9 pin mini, 6AV6 with symmetrical plate as a 7 pin mini and diodes tied to plate, and a 7B4 seated in a loctal socket.
There are compromises in any and ALL choices of high mu driver tubes for a direct coupled JJ 2A3-40 amp.
For example, the latter two tubes I mentioned are more microphonic than the first tube mentioned, but when employed just one time on the input, its OK in real-world use. The latter two tubes have symmetrical plate-filament-grid structures. All three tubes given as examples, are mu of 100, thus are preferable, normal listening-wise, to a 6SL7 octal-based tube IMHO.
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Topic - Neutralization of Miller capacitance - sser2 15:29:24 03/11/17 (24)
- Why not just use a 6SN7? - Ralph 12:11:36 03/13/17 (10)
- 6SN7 - sser2 14:15:47 03/13/17 (9)
- 6SL7 - drlowmu 00:20:05 03/20/17 (8)
- RE: 6SL7 - GeorgePope 01:36:42 03/20/17 (7)
- Four legs good, eight legs bad??? - cpotl 17:54:16 03/20/17 (2)
- RE: Four legs good, eight legs bad??? - used-hifi 18:00:54 03/20/17 (1)
- RE: Four legs good, eight legs bad??? - PakProtector 04:33:05 03/22/17 (0)
- RE: 6SL7 - drlowmu 08:53:34 03/20/17 (3)
- RE: Neutralization of Miller capacitance - Lew 10:29:28 03/12/17 (5)
- RE: Neutralization of Miller capacitance - sser2 13:40:42 03/12/17 (4)
- RE: Neutralization of Miller capacitance - megasat16 16:06:26 03/11/17 (0)
- RE: Neutralization of Miller capacitance - Tre' 16:00:06 03/11/17 (5)