Recommandation please..

[e_fortier]

Hi,

I have a power transformer rated 240Vac, 80VA that I would like to use...please see attached dwg, the B+ at full load is about 300-320Vdc and 200mADC is available for a stereo application.

I have never built PP so maybe that would be nice.

So far my amps are;
Chinook (SET 2.5W) with 13FD7
RH84 (6BQ5)
RH807 (807)

I'm presently working on a 12AV5GA SET (triode strapped pentode) with 6N6P driver and CCS on driver.

If you have any idea as to what I can use my power transformer for please let me know.

TIA,
Eric

[e_fortier]

Any help ?

I do not know tubes characteristic enough to know which output tube I can use with such available B+ and Ia, can a design be done using GU-50, GU-19, 4P1L with my power transformer ? Is some one know a very goo sounding tube please be my guess and let me know.

TIA,
Eric

[nightanole]

With your b+ you could do most el84 PP setups.

tubelab simple pp
the baby huey
the red light district
the podwatt

[the_manta]

You only have 100mA for one channel left then.
1625 is a bit tight calculated. But EL84 is fine (Class AB)
There are kind of million circuits for PP EL84 available, so choose one.

[e_fortier]

I forgot to mention that I bought a few months ago a set of CXPP25 8K OPT from Edcor, I will use them to built a nice sounding EL84 PP, so for now I would rather avoid building a EL84 power amp. Any idea with more odd tube like RCA 832, GU50, etc...

Thanks,
Eric

[quikie22]

single ended GU-50, using 8k SE OPT... use 6AU6 to drive it with local feedback..

Edit: Just noticed you had a RH807, you could try a RH-50, but using GU-50 instead and instead of a 12AT7 as driver, use a pentode driver eg 6AU6 or EF86 or even EL-84 as a driver. You might like it... I certainly like my pentode driven 6E5P driven GU-50 with local feedback :-)

[e_fortier]

Hi Quikie22,

I already have a few 6AU6 but EL84 driver sound even better ;-)

GU-50 with EL84 or 6AU6 driver with local feedback sure sound like a win win situation, can you share some feature of your design like operating points of driver and output tube because I used the 6AU6 as driver on my RH807 and couldn't get the amp to sound right...

Thanks in advance,
Eric

[e_fortier]

Looks like the 6E5P (which I didn't know about) is a heck of a driver, you could use it to drive GU-70 or 6C33C...nice to know. I wonder how the 6N6P compare to the 6E5P as far as driver...

Thanks !

Rgds,
Eric

[e_fortier]

Hi all DIY's,

So far I have found a 6E5P/GU-50 SET Amp schematic which is fixed bias with Ia around 80-85mA for the GU-50 and ?? for the driver..which is quite a tight fit for my 100mA/channel...

Rgds,
Eric