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Doug's Tubes evaluation

Posted: Mon Jun 21, 2010 11:41 am
by MojoFly
I just got a set from Doug's. Seems the Express's four modes is a common challenge for most of us to tame. Hopefully, these observations can help others.

First, I do think it's worthwhile to review the Tube Task Chart to get an appreciation of each positions purpose. The goal being to capitalize on Mesa's engineering for the Express design. I keep with the basic strategy of V1 - V3 = the gain escalation tubes and V4 - V5 = the output tubes.

Disclaimers:
(1) Tubes: By engineering will vary by brand, design and voltage. So even if we installed the same tube on paper, our results could certainly differ.
(2) Speakers: Probably should be a thread of its own, but needs to be stated: Your results will vary between your speaker choices. Having a combo, I kept my observations constrained to just the C90. **Soundchaser59 would be the best forum resource in this arena**
(3) Player Preferences: **Includes guitar choices ** Obviously we each have our styles of playing and dial preferences. Makes the musical world go round. :wink:
(4) Dial positions: Each tubes change will affect the results in our dial zones (G – T – M – B – R - Mstr – Contour)

Background: Coming from some limited Mesa experience (20/20, Heartbreaker, Triaxis, F50) to the Express 5 50, I think most would agree the Express can be difficult to drill in on tones with its stock complement of tubes.
With my other Mesa's, I’ve always had great success using JJ's throughout as with my other amps. This is not the case for the Express. Using this formula (ECC83S's throughout) in the Express, I gotta agree the results here were less than expected. :( (For my initial tests, the only 6L6's I had on hand were a matched pair of JJ's and the Mesa's)
I’ll spare you all the incremental experiments and share my best results to date as compared to Doug’s basic list.

Doug's List
- V1 Tung sol 12AX7
- V2 High Gain JJECC83
- V3 Penta 12AX7
- V4 Shuguang 12AX7 9th gen
- V5 Sovtek LP/LPS
- SED 6L6GC Matched

Ordered/Installed
- V1 Ruby 12AX7ACZ HG
- V2 Tung sol Gold Pin
- V3 Penta 12AX7
- V4 Penta 12AX7 Balanced
- V5 Sovtek LP/LPS
- SED 6L6GC Matched (Average Distortion)

Granted everything list above is not “apples to apples” notably:
(1) I received Ruby 12Ax7ACZ HG instead of the JJ 83 HG’s I ordered. (Upgraded replacement :?: )
(2) I chose a balanced Penta 12AX7 for V4, because:
a. Shuguang’s weren’t available individually (I already had a Tung Sol (Gold) so didn’t need the re-tube set)
b. For a few dollars more , I wanted a balanced tube to be used in the phase splitter/driver position

In essence, I would say the most notable change anyone could do for the Express is to switch the V1 & V2 as installed. In fact, when I ran the Tung Sol in V1, I found it too “chimey” i.e. high strings had this “after note” echo thing going on.
Installation results appear to take full advantage of the V1 – V3 cascading positions.

Yeah… Perhaps the balanced V4 may be a “placebo”, but I figure if I’m spending $$ on a re-tube, getting a balanced tube in V4 wouldn’t break the bank.

Can’t say whether the Sovtek LPS were really necessary being the Reverb output tube, but it works well anyway.

Installing the preamp tubes as described (at least for me) really delivered the resurrection of soul I was seeking in all four modes. In fact, I finally got the coveted Chl 2 “growl” back I missed so much from my F 50. I was beginning to think I made a mistake changing over. I gotta believe the SED 6L6’s contributed here as well.

Suffice to say all four modes now offer the tonal palettes I was always hoping for in this amp.

The Express is truly a hybrid product with it’s four character modes leveraging Mesa’s quality engineering.
It’s hard to describe, but having this tube compliment in place, makes each mode selection more logical.
i.e. Think… Clean = Clean, Crunch = Crunch, Blues = Blues, Burn = Burn.

Having always favored the Chl 1 modes, I now find that having a useable Chl 2 on tap offering “soulful” Blues and the growling gain in Burn clearly has increased the tonal real estate housed in this amp.

Re: Doug's Tubes evaluation

Posted: Tue Jun 22, 2010 5:55 am
by Newysurfer
Hey great review Mojo :mrgreen:

I've found similar using Doug's standard list.
Would never go back to the Mesa stock tubes.
Sounds like your variations to Dougs list have been a success so ....happy playing

One thing you haven't mentioned is amp humm.
Have you got a big reduction there ?

Re: Doug's Tubes evaluation

Posted: Wed Jul 14, 2010 9:08 pm
by MojoFly
Newysurfer - Didn't mean to bypass your question before. Just had to think about how best to respond. Here goes...

First, the very nature of tube amps will always involve some degree of Hum, Hiss or White Noise. Some companies handle these better than others.
Mesa by standard happens to be one that does a good job here.
The real question comes down to: what degree of noise is "tolerable" while achieving your tones.

By comparison, I do find a smidge more noise (on some settings) in my Express over other Mesa's I've owned. But it would be unfair to just "broad-stroke" that statement without regard to the tone quality the Express delivers.

An unrelated example would be my having a Genz Benz El Diablo 60 before moving to the Express. At that time, I spent a lot of time directly A/B comparing my F50 to the El Diablo.
A buy-product of that comparison revealed considable noise from the Genz Benz over the F50 and the Diablo delivering less soulful tones.
Feature-wise I liked Diablo's offerings, but couldn't get hooked on the tones or it's noise.

Now that I have the Express, it's true, I still detect some minor noise on select high gain settings. But nothing compared to Mesa's competition enough to be dis-suaded to what is being delivered soundwise.

So, for me, any noise the Express delivers I can control and the tonal benefits still out-weigh any shortfalls.

Re: Doug's Tubes evaluation

Posted: Thu Jul 15, 2010 2:43 pm
by vbf
There was a recent thread in which switching the tubes in V1 and V2 was discussed for reasons that seemed good at the time. :) I switched the tubes in V1 and V2 and have been happy with it. If anyone can find and link it, that would be great.

Re: Doug's Tubes evaluation

Posted: Thu Jul 15, 2010 5:50 pm
by EtherealWidow
I don't know about a link to the thread, but the reason for switching V1 and V2 is because of the way the Express is designed. Doug's tube kit is designed for most normal amp tube paths where V1 is the first gain stage, V2 is the second, etc etc. The Express (and some other Mesa's too) is designed differently from most in that V2 is the input tube and first gain stage, meaning that the overall tone is influenced most by that socket. Then it goes, V1 and then V3 and so on. So when buying tubes for the Express, make sure that you're aware that your guitar signal is FIRST going into the V2 position.

Re: Doug's Tubes evaluation

Posted: Thu Jul 15, 2010 7:08 pm
by vbf
Thank you for the clarification.

Re: Doug's Tubes evaluation

Posted: Sat Jul 17, 2010 7:32 pm
by Newysurfer
MojoFly wrote:Newysurfer - Didn't mean to bypass your question before. Just had to think about how best to respond. Here goes...

First, the very nature of tube amps will always involve some degree of Hum, Hiss or White Noise. Some companies handle these better than others.
Mesa by standard happens to be one that does a good job here.
The real question comes down to: what degree of noise is "tolerable" while achieving your tones.

By comparison, I do find a smidge more noise (on some settings) in my Express over other Mesa's I've owned. But it would be unfair to just "broad-stroke" that statement without regard to the tone quality the Express delivers.

An unrelated example would be my having a Genz Benz El Diablo 60 before moving to the Express. At that time, I spent a lot of time directly A/B comparing my F50 to the El Diablo.
A buy-product of that comparison revealed considable noise from the Genz Benz over the F50 and the Diablo delivering less soulful tones.
Feature-wise I liked Diablo's offerings, but couldn't get hooked on the tones or it's noise.

Now that I have the Express, it's true, I still detect some minor noise on select high gain settings. But nothing compared to Mesa's competition enough to be dis-suaded to what is being delivered soundwise.

So, for me, any noise the Express delivers I can control and the tonal benefits still out-weigh any shortfalls.
Mojo - ahh you missed my point buddy - or rather my question.
When I changed tubes to Dougs recommended ones I got a 50-60% reduction in amp white noise.
I'd specifically asked Doug for low noise tubes & he delivered well.
So I'm asking you if you've noticed far less amp humm with the new tubes :mrgreen:

Re: Doug's Tubes evaluation

Posted: Fri Dec 17, 2010 3:51 pm
by Mark 63
As the year is winding down this week, I've had some time to play around with different preamp configurations, starting with the mix that Doug put together for my 5:50 after Thanksgiving:

V1 Tung Sol 12AX7
V2 JAN GE 5751
V3 Penta 12AX7
V4 Sovtek 12AX7
V5 Penta 12AX7
=C= SED 6L6

Right away, I found a great improvement over the stock Mesa tubes. I'm mostly using the Blues for clean/Crunch for distorted arrangement (I play a Stratocaster with Knopflerian aspirations).

So, I thought if one 5751 is good, 2 would be even better, and ordered a pair of NOS GE greyplate 5751 from KCA. But after a few days of configuring them, starting with V1-V3 all 5751, I found that Doug's combo was head and shoulders the best for me.

One 5751 in V2 is gold. More than one 5751 results in too little gain. And I preferred the JAN GE 5751 to the GE greyplates, which cost twice as much.

All in all, Doug's combination gives me good musical overdrive, reduces (but doesn't eliminate) the channel 2 hiss. It enhances the touch sensitivity of the Mesa design beautifully.

Re: Doug's Tubes evaluation

Posted: Sat Jan 07, 2012 11:27 pm
by enigma
Looking from the back of the amp, does V1 start from the left or the right?

Re: Doug's Tubes evaluation

Posted: Sat Jan 07, 2012 11:44 pm
by thunda1216
V1 will be closest to the input jack.

Re: Doug's Tubes evaluation

Posted: Sun Jan 08, 2012 7:54 am
by enigma
thunda1216 wrote:V1 will be closest to the input jack.
Thanks!

Re: Doug's Tubes evaluation

Posted: Sun Jan 08, 2012 9:30 am
by EtherealWidow
This amp is different. V2 is the very first gain stages in both Expresses, then V1, then V3, then parallel into V4, then into V5, then power tubes.

Re: Doug's Tubes evaluation

Posted: Sun Jan 08, 2012 11:56 am
by enigma
EtherealWidow wrote:This amp is different. V2 is the very first gain stages in both Expresses, then V1, then V3, then parallel into V4, then into V5, then power tubes.
So, I should first replace the V2 tube, right?

I just put Tung-Sol in the V1 and V2 position, but don't hear much improvement. I really think it's the nature of Express circuitry that's just not working for me tone-wise. I'll give it another week before thinking about selling or trading to another Mesa (Maverick) or something else.

Re: Doug's Tubes evaluation

Posted: Sun Jan 08, 2012 5:14 pm
by EtherealWidow
Changing V2 will result in the biggest change in tone. And yeah, you might just not like the tone of the Express. :/

Re: Doug's Tubes evaluation

Posted: Sun Jan 08, 2012 6:43 pm
by enigma
EtherealWidow wrote:Changing V2 will result in the biggest change in tone. And yeah, you might just not like the tone of the Express. :/
I was hoping even for a small change! :)