Do 12AX7 tubes distort more "musically than solid state stages?

[JimRayden]

Like anything else it's about the design. Tubes can sound brilliant or like ass. It's all in how you use them.
Ron

Absolutely !
I have a tube distortion by Martin Owen    www.owenelectronics.co.uk/9916.html
It sounds VERY nice and has a great TMB tonestack, I'm NOT going to pull it to bits
and reverse it, as he's a gent and a very helpful guy who's running a small operation.
Whatever he got up to inside it ... HE got it right !!

MM.

Space charge, huh? You might want to consider checking out Vox's Cooltron line, those use the same method. It's basically about starving the heater rather than only the plate.

----------
Jimbo

[bancika]

starving heaters will make tube last much, much shorter then usual.

[Rafa]

Hi:
As far as I know part of the distorion in a tube amp comes from the preamp as we`ve tlaked here. Output tube distortion is said to be  ``softer´´ so I was wondering how much gain can you get from the output tubes when the amp is at max. Is just a crunch or is it as gainy as preamp tubes? Has anybody tried using a clean preamp to overdrive a tube power amp?
Cheers
Rafa

[bancika]

I think that AX84 firefly gets good part of it's distortion from overdriving output tube

[mac]

Honestly I never heard a tube preamp distorting on its own, I mean a good or well-known preamp, ie twin, jcm, ac30, etc.
Also, as physicist I can describe a tube or ss, but I don't know how to put them to work in a 'musical way'... yet. So at first sight, if I see a circuit I can't tell if its going to work well or not, though I am begining to visulize things. Of course I know about electromagnetism and my formation help me to undesrtand things quickly, but I'm not an elect eng. So my opinion is not based on technical facts.

The Fuzz Face is a ss preamp, and a nice one. I connect it to the clean channel, let the signal pass through the amp's preamp as clean as possible and then hit the OT, power amp and speaker. I don't know how the power section colorize the signal, but it certainly do its job better than most of the ss power amp I heard, except the jazz chorus.

So my answer to Aron's question is that in some cases ss preamps, like some stompboxes, are very musical.

But nothing compares to the warm sound of the power tube amp... a little gain and a cranked master.


mac

[brett]

Hi

As far as I know part of the distorion in a tube amp comes from the preamp as we`ve tlaked here. Output tube distortion is said to be  ``softer´´

The 18W is an amp that, when used with an unboosted guitar, gives plenty of output distortion (and maybe phase-inverter?) and only a little pre-amp distortion.  The distortion is definately not soft, unless that's how you would describe early ACDC.
IMO the phase inverter and output transformer are overlooked sources of distortion.  The former is easy to overload, and the latter provides quite a lot of colour, especially at high power, where  compression and "ringing" and falling frequency response occur.

Concerning the 12AX7.  It is fairly obvious why lots of designers use the 12AX7.  It is the low noise and high gain and low cost and ready availability.  What more do you want for $10.     Good quality altternatives are usually more expensive than 12AX7s.  I sold two pairs of ECC801/01s for $200 a pair and bought a whole amp (a JTM60 with 4 12AX7s, 2 EL34s, transformers, two celestions, etc in it).  Will I miss those really excellent tubes?  Heck no!
cheers