hi Fi tubes for geetar amps?

[tubeswell]

I stumbled across this factory in the Czech Republic that hand-makes HiFi tubes. Their range apears to be all directly-heated tubes, although if you used one or more of the high voltage triodes in parallel you could probably build a single-ended amp (with a specially wound PT and OT). I have some friends going to Prague for a business trip. So I might get some and see (or I might not). What would directly-heated tubes go like in a guitar amp?
http://www.kraudio.com/

[dai h.]

if you want them go for it, but IMO a lot of esoteric and expensive parts don't seem to be a good value as much as technical know how. If it was me going I might try to find sources for old stock Tesla tubes (not JJ) and maybe buy some older EL34s and ECC83(or types such as E83CC) if they could be found for less.

[Steve Conner]

For some reason a DHT powered guitar amp makes me think of piano bars, cocktails and hollowbody guitars. Not to mention a seriously empty wallet, since the KR 300Bs, for instance, run at $500 a pair.

That in a nutshell is the issue with DHTs, they are high priced products marketed at audiophiles, to make single-ended amps with smooth, jazzy low-order harmonic distortion, and they cost a lot per watt delivered. For average rock guitar use, you just want the loud, aggressive grind and clang of a couple of beam tetrodes or pentodes that you can pick up for $25 each. (Which, by the way, made DHTs obsolete when they were introduced in the 1950s. Compare the mu and gm figures for a 300B and an EL34 to get an idea of the improvement.)

But they look beautiful with the filaments on. I know a guy who made a hi-fi amp with a solid copper chassis and mesh-plate 300Bs, and it looked absolutely stunning. But at $250/tube, it had better.

[tubeswell]

I found a price list for the Czech made tubes. For new tubes they sure beat everything else hands down

http://www.worldsbesttubes.com/

http://www.worldsbesttubes.com/tube%20msrp%20list.html

Tho' they look fantastic. I almost feel obliged to get some to help keep artisans producing. Maybe when I'm feeling richer ;-)

[jrfrond]

I recently restored the amp and power supply for an RCA StoryTone piano, a real museum piece (Google it and find out!). Anyway, the amp/power supply combo was built by RCA, with 4-2A3 triodes for a grand 26WRMS. While it was still on my bench, I plugged it into a 4 x 12 cabinet (Jensen-loaded) and plugged a guitar into it. Sure, it amplified the guitar, but was flat and unimpressive sounding, whereas when installed back into the piano, it was pure, clean magic.

Hi-Fi tubes and amp designs have their place, but usually NOT in guitar amps. They just do not have the proper response and coloration.

[Enzo]

If any doubt about that remains, just plug your guitar into the AUX input of your home stereo. Bleh.