other pentodes

[Andy Le Blanc]

What other af pentodes are out there?

There's 6sj7, 6au6, Ef86.... What else is out there ?

How about Russian equivalents?

[M Fowler]

6SQ7 and 6SC7.

[Andy Le Blanc]

6sc7 looks to be metal type duo triode with a shared cathode.
6sq7 is a metal type duo diode high mu triode.

there are several rf pentodes like 6sj7, sk, sh,sg sf, but radio types dont
always cover AF well.

theres the 5879, but the voltage gain is less than 200, theres a few IF 7 pins.
6cf6....

[M Fowler]

You can get both tubes in glass Andy.

[Andy Le Blanc]

So.... there's the 6sj7 russians cv591, and vt116a, how are these?
Haven't even tried to source them.

ef94?

Yes, GT is nice, I don't mind metal types, they got they're own tone.

[breakfastbuddy]

the 6ac7 is a 6sj7 tube with more gain .

[10thTx]

5654

[flood]

disagree about rf pentodes, or rather, about 6SJ7s. did an octal fatness type affair, and the 6SJ7 channel sounded fabulous.

[Andy Le Blanc]

I like 6sj7 very much too, but you can't make assumptions.

5654.....ummmm.... that's a 6ak5/EF95...... 7 pin rf/if
Did you try it in the application?

6ac7 looks neat, I got a sheet that classifies it as a "television amplifier pentode"

6AC7 / 1852

Ill dig around in the bones....... Ive tried and like 6sj7, EF86, even 6au6.

12au6 and 6au6 were in scads of practice amps, harmony, silvertone, wards, etc...

[Phil_S]

I've got 7 6AC7's. They came as part of a mixed lot and were an unwanted bonus. If you figure out what to do with them, please do let us know! These are all metal jacketed, not glass. I'm willing to send you a couple to play around with, if you can't find any in your bone pile.

[Andy Le Blanc]

I do have a 5654..... fun.... the rating for those is nutz, durable for mil. app..

but no 6ac7.. many other remote cut off's.

[M Fowler]

I sure like those 6SQ7 tubes in my Gibson EH150 I recently built such a great change from 12AX7 tubes.

[Andy Le Blanc]

Any change from 12ax7 is wonderful, most manufacture s use them so everything sounds the same.
No bandwidth.

[Firestorm]

I don't know how practical it is since the sockets are less commonly findable, but there are quite a few 10- and 12-pin tubes with one or two pentode sections. Not too many TVs from the tube era being repaired, so NOS supply is probably decent. Of course, no one will ever make more, so you might wind up designing an Ampeg with 6BK11s -- gone, gone, gone.

[lumox0013]

would a 6eu7 be usable as I have a bunch of these from a teardown,anyone know an amp that uses these,also for a while now I have wanted to do an all octal rocket w/ a quad of 6v6 and all octal front end w/ 6sj7s 6sc7s? anyone try anything like this yet?