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I recently invested in a few different tubes for my amp which only has room for a single preamp tube, the rest is solid state. I thought I'd share my findings with you. I could hear and feel a pretty nominal difference while playing through the amp, but to be honest I strain to hear the difference in the recordings, maybe your experience will be different.

I recorded two DI tracks, one clean and meant to be played dirty. I sent them from Logic Pro through my PreSonus FireBox then to a Radial ProRmp into my B. K. Butler Designed amp head through a Crate 4x10 mic'd off center with an SM57 finally back into the FireBox and into Logic Pro again... got all that? :D

The Tubes Used:
Mystery Tube - I'm not sure what tube this is, but it's a 12ax7 that came with the amp
Ruby - 12ax7 AC5 HG+
Mullard - 12ax7
Tung-Sol - 12ax7

Here are the files for download:

;)
;)

Comments

moonbaby Thu, 10/08/2009 - 10:15

G-Freak:
From what little I've heard of your playing, you are a talented young man.
But these cheap little solid-state amps that use a single 12ax7 tube in the preamp stage are simply designed to provide fizzy-fuzzy distortion based on "starving" the plate voltage to the tube. In these cases, that results in a harsh, non-linear distortion like transitors do. It's got a tube for marketing hype more than any real musical advantages. Any real differences between tubes used in this way are usually noise issues, not so much tone. Hence, this "shoot out" is a "moot shoot"...

Guitarfreak Thu, 10/08/2009 - 13:00

moonbaby wrote: G-Freak:
From what little I've heard of your playing, you are a talented young man.
But these cheap little solid-state amps that use a single 12ax7 tube in the preamp stage are simply designed to provide fizzy-fuzzy distortion based on "starving" the plate voltage to the tube. In these cases, that results in a harsh, non-linear distortion like transitors do. It's got a tube for marketing hype more than any real musical advantages. Any real differences between tubes used in this way are usually noise issues, not so much tone. Hence, this "shoot out" is a "moot shoot"...

Thanks for the feedback! :D I get where you are coming from, I wish I had an all tube signal path amp but it's overkill for me right now, I don't even have a band at the moment. I just thought I'd share my experience with the forum considering you guys are so helpful.

Guitarfreak Thu, 10/08/2009 - 19:34

jg49 wrote: I listened and did nothear such a significant difference that I was like wow thats the one. The tungsol sounded best but not much....

I agree, that's pretty much how I perceived the clips. The experience was a bit different though.

I've got the Tung Sol in there because it exhibited the least noise and most gain, so for only having on tube spot it seems that's the best bang for buck.

The Ruby tube seemed to have more of that warm 'analog' feel like it was rounding out the transients, very pleasing on the clean channel. The only drawback was that there was less gain, It would probably be my first choice if I had tubes cascading eachother, but one by itself just doesn't produce enough.

The Mullard just had that fat older Marshall feel to it, it was a lot like the tung sol because of its gain and presence but the breakup seemed more 'wooly' with more lower mid response.

The original tube just didn't have any redeeming qualities, not very much gain, and dull tone (which is different than warm tone).

It's just a shame that this experience didn't show up on tape, but perhaps the experience was the playing with the settings and seeing how each tube 'responded' and the shootout was a snapshot that doesn't tell the whole story. Well, one way or another, now you know. If I had an actual tube amp with multiple tubes I would assemble the Preamp section this way...

V1 - Tung Sol (For its power and clarity)
V2 - Ruby (For the warming aspect and fatter tone)
V3 - Ruby...
V4 - Ruby...
and so on, for however many tubes there are in the preamp section. But if there were five slots I'd probably put the first two as tung sols and the next three as Ruby's. And so on, I am sure you get the point.

rmburrow Sat, 10/07/2017 - 09:58

Guitarfreak, post: 292018, member: 49161 wrote: I agree, that's pretty much how I perceived the clips. The experience was a bit different though.

I've got the Tung Sol in there because it exhibited the least noise and most gain, so for only having on tube spot it seems that's the best bang for buck.

The Ruby tube seemed to have more of that warm 'analog' feel like it was rounding out the transients, very pleasing on the clean channel. The only drawback was that there was less gain, It would probably be my first choice if I had tubes cascading eachother, but one by itself just doesn't produce enough.

The Mullard just had that fat older Marshall feel to it, it was a lot like the tung sol because of its gain and presence but the breakup seemed more 'wooly' with more lower mid response.

The original tube just didn't have any redeeming qualities, not very much gain, and dull tone (which is different than warm tone).

It's just a shame that this experience didn't show up on tape, but perhaps the experience was the playing with the settings and seeing how each tube 'responded' and the shootout was a snapshot that doesn't tell the whole story. Well, one way or another, now you know. If I had an actual tube amp with multiple tubes I would assemble the Preamp section this way...

V1 - Tung Sol (For its power and clarity)
V2 - Ruby (For the warming aspect and fatter tone)
V3 - Ruby...
V4 - Ruby...
and so on, for however many tubes there are in the preamp section. But if there were five slots I'd probably put the first two as tung sols and the next three as Ruby's. And so on, I am sure you get the point.

I never liked 12AX7's. Most are microphonic or noisy. They have high gain (u = 100) but there are compromises with high gain. If you are a DIY type and careful around voltages involved with tube gear, there are nice schematics of preamps out there using the ECC88 (6922/6DJ8), EF804, 12AT7, 7721 in triode, 5879, EF86, 6AK5, etc. The most expensive part of a DIY preamp are the input and output transformers. Sometimes nice tube preamps can be found on the used equipment sites (i.e. Gates M5215, etc.) but you will need to come up with a well filtered 300 v DC (HT) and 6 v dc (filaments) to run them. Do not overpay for used gear since electrolytic caps should be replaced for starters... The Gates M5215 can be cloned and if the original transformers cannot be located, UTC or other "iron" will work....DO NOT ATTEMPT THIS if you are uncomfortable with DIY projects or working around 300 volts or more...