Posted by Damir [ 213.202.111.2 ] on February 28, 2006 at 14:31:39:

In Reply to: Anyone use 6S45P with 12B4A concertina for PP 7591A or 6L6? posted by Norris Wilson on February 28, 2006 at 13:20:00:

No, I didn`t, but if you don`t need the NFB than you can use something like this - 5687 concertina, works with E182CC, too. 50k resistors (R7,R8) are actually grid-leak resistors of the output tubes. With them, and 5687 you can get about 2x27Vrms out with 2Vrms input, it`s about 2x38Vp, or about 5dB of "headroom" for -22V (needs max. 22Vp) biased 7591. With E182CC you can get about 2x32Vrms out(2x45Vp) - enough even for 6L6.
The current through 1st and 2nd stage is 10,5+10,5mA. I used something like this in my PPP monoblocs, and when I find some time I`ll put the CCS in the place of 27k resistor, stay tuned...

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