Tube Repro
- Thread starter jcmusic
- Start date
Hello Jay,
I would highly recommend a pair of RFT EF86's, and the best 7308 you can afford (in place of the 6922). Getting good EF86's is a bit of a crapshoot, so if you decide you want to go with mesh plate EF86's, I would buy at least 4 of the same type to make one good pair.
The 6CM7's don't have quite the influence that the higher gain tubes have, and I have found that all the various old stock varieties have their own strengths.
-Paul
I would highly recommend a pair of RFT EF86's, and the best 7308 you can afford (in place of the 6922). Getting good EF86's is a bit of a crapshoot, so if you decide you want to go with mesh plate EF86's, I would buy at least 4 of the same type to make one good pair.
The 6CM7's don't have quite the influence that the higher gain tubes have, and I have found that all the various old stock varieties have their own strengths.
-Paul
Yes, there is a slight difference. The single ended output has one less tube gain stage and is a cap coupled output. The balanced output has that additional gain stage triode and a transformer output. I find that the single ended output is maybe a little more neutral tonally and perhaps has a bit more precise imaging if the load it is running into is acceptable high, at least 15K (but 50K is probably better). To my ear the balanced output has a little more punch and more bass "balls", and of course it can drive loads clear down to 500ohms. I guess I ever so slightly prefer the balanced output (and my current preamp setup requires that I use it), but the differences are pretty small and it is pretty much a matter of personal taste.
jcmusic said:
I have to warn severely against doing this. Having built most of the Repro amps available in circulation, I can comment that the design is not convenient for parts swapping. This is especially true in the EQ network where I build everything compactly and tightly to minimize any movement in shipping. This also means that to roll EQ caps, you might have to remove eight or ten resistors in the process.
I can, however, say that Doc may be amenable to taking in a Repro for modifications. These could include:
1. New Front Panel color
2. Alternate EQ capacitors/EQ modes (this will generally necessitate a new front panel for reasons mentioned above)
3. Alternate coupling capacitors
With all that was thrown into the Repro, it is actually pretty difficult to come up with crazy ideas to make it a lot better (we discuss this quite a bit without much consensus).
-PB
