ECF80/6BL8

[Tobruk]

Ecf80/6bl8

Hi,
I would like to use this tube in a 6BQ5 PP amplifier.I am looking for a schematic..Thanks
regards

Franco.-

 

[Eli Duttman]

Franco,

The 6BL8 is a nice tube. However, there's (IMO) too much gain for use with EL84s. A "knock off" of the Dyna ST70 with PP EL34 "finals" seems better to me.

 

[Tobruk]

What you think about this schematic...

 

[Miles Prower]

What you think about this schematic...

The trioded pentode section will probably need a screen stopper to prevent instability, and I'd lose that 47R resistor. It won't do any good unless it's on the order of 1/g(m) anyway. A g(m) on the order of 21mA/V is awfully high for hollow state.

 

[Johan Potgieter]

Hi Tobruk,

I kind of sense that your separate threads regarding the EL84 p.p. amp are all related. If so, why not ask a moderator to throw them all together, and you will have all the advice under one heading, instead of in separate places where folks who are able to help might overlook them?

Regards