EL84 or 6v6 or something else?

[svokke]

This will be my first hifi tube project, I have a lot of experience building guitar amps and repairing tube stuff.
I've got two hammond 125E transformers and two power transformers (230V/120mA, 6.3V 4A). The hammond is rated at 15W and has many primary impedances: 1k2 to 20K.
Now I'm planning to build two monoblocks for use wit my B&W DM4. These are bookshelf speakers with a sensitivity of "4.8 watts into nominal impedance (i.e 6.2 volts) for a sound pressure of 95dB
pink noise at 1 metre". Power handling is 25W
The DM4 are used with a subwoofer, so frequency response below 80Hz is not so inportant.
I still have to choose some tubes. I want to use a 6SN7 in the preamp, but can't decide what to get for the power amp. It should be a tube with a good availability like EL84(6bq5), 6V6, SV83, ECL82 (6BM8),...
How can I choose between these?

 

[Fuling]

Don´t forget 6AQ5, aka EL90.
I have good experience of these and at least here in Sweden they are (very) cheap and easy to find.
They are electrically almost identical to 6V6, only a little bit weaker.

 

[G]

I would go for a SE EL34 with a 6SN7 driver. Go all octal. That is going to be my next project. After I finish the one I'm working on now of course.

Gavin

 

[zobsky]

I still have to choose some tubes. I want to use a 6SN7 in the preamp, but can't decide what to get for the power amp. It should be a tube with a good availability like EL84(6bq5), 6V6, SV83, ECL82 (6BM8),...
How can I choose between these?

amongst your mentioned choices, .a 6sn7-6v6 or 6sn7-el34 stand recommended

the el34 will have more power but the midrange of the 6v6 is something special

 

[Fuling]

SE EL34

The Hammond 125E isn´t suitable for SE use.
You guys are probably thinking about 125ESE transformers, which is a different animal.

 

[G]

You could build a nice little push pull, triode strapped, 6v6 amp and get very nice sound at moderate levels if you bias them to run hot ( 90% of rated current ). At low signal levels the amp will be working in the "class A" region and you will hear the glory of class A triodes doing their thing. here is a link to a PP 6BQ5 PP amp that was originally designed my Magnavox engineers ,when magnavox was known for solid design and solid performance, and tweaked into a excellent design by Gabe V, one of the regulars on this forum.

http://members.tripod.com/~gabevee/pptube.html