The TUBES Thread

[bigwebb83]

Wanted to make a thread for discussion of tubes.  What works, what doesn't.  What's worth it, what isn't.  I'm always looking to improve the sound of my gear and I know tubes are one way to do that.  I also know that some tubes just aren't worth what they cost.  So I'll start out by asking what tubes are you guys running in your preamp and power sections?  What changes have you made that you thought were successful.  I'm really big on the clean channel so that's where my focus will be.

[SoundPerf]

I'm using TAD 6L6 WGC STR's and I'm quite happy with them as far as production tubes go.

I guess the most important discovery and significant difference I've made was buying a NOS RCA Short Plate 12AX7. I realize this is a no-brainer for many around here, but I'm not one to want to spend lots of money on tubes. But this convinced me of the worth. I originally got it for my D-lator (which sounded great) but then decided to put it in V1 of the amp. What a great sound! If you looking for better cleans, then this is what you want to do. There are other good NOS choices also for V1, but I really like this.

I have some Tung Sol RI 12AX7's in V2 and V3 and took the one I had in V1 and put it in the D-lator. I was/am happy with these tubes also. But very likely when it comes time to totally retube the amp, I will get all NOS. That is, if I can find them and afford them. 

[plasticvonaband]

After alot of tube rolling in my HRM Bypassed Bluesmaster, I am liking ANOS GE Long Plate in V1, JAN GE 5751 in V2 and Groove Tubes 12AX7-R in V3, either TAD 6L6WGC STR's or JAN Phillips 6L6WGB's in V4 & V5. I use a low noise  7025 in the C-Lator

[plasticvonaband]

Mike @ kcanostubes.com. Nice guy and reputable.

[CeeEm]

To add another thought in here... I put a set of Mullard re-issue EL 34's in my 100 watt Bluesmaster and it changed the character of the amp in such a great way. It has a much tighter bottom, more pronounced mids, and more gain at lower settings on the OD section.  I use Tung-Sol 12AX7's in the pre-amp section.

[CeeEm]

Bluesmaster 100 with 6L6? Can you run it with EL34 safely? (just need to rebias?)

Yes definitely Homesick. I took it to my tech ( I'm not a builder or tweaker myself, I take it to him and have him do it )
and he re-biased at 33-34 mA. He doesn't like to run them too hot - others do. I believe quite a few of the Dumble BM's were EL34's. I really like the differences in mine.

[bigwebb83]

thanks for the responses guys.  keep em coming.  Anyone else using a 5751 in V2?  How does this affect the sound?

[plasticvonaband]

thanks for the responses guys.  keep em coming.  Anyone else using a 5751 in V2?  How does this affect the sound?

in my rig, it helps a little with the volume jump that comes with bypassing the HRM tonestack. It also helps tame the high ends and helps shape the mids in a pleasing way through the Weber 1265 Alnicos. The OD sound is very Cranked Tweed or BF Bassman depending on how you have the tone controls set and can go from fat to mildly compressed depending on where you have the OD trim and drive set, and it sings. I have found that about 11 o clock on the OD trim, and just a hair over 7 out of 10 on the drive is the sweet spot. kick the clean boost in and it will make you giddy nice cranked bassman/early marshall growl. kick in the standard PAB and the clean boost, you are in plexi country with still a fendery vibe. kick in the modded PAB (tone stack completely lifted via a 22M resistor vs the 68k standard) you are in modded plexi country. Modded PAB and clean boost, well, it's like nothing i've ever heard and it's AMAZING!

************edit*******
i should add that a like a warm, thick, singing tone and ALOT of my tone comes from the Long Plate GE in V1 and the 6L6WGB's in V4 & V5, running at 70% idle dissipation. I also have my PI set to a 7 volt swing instead of a 6 volt swing which really helped the bloom and sustain with my setup.

Gregg

[212Mavguy]

I have two tube stores.  Main one is ebay, other is a private tube vendor who is a friend of mine an hour drive away. 

Started collecting my tube stash 6 years ago, got all I want.  Also have some nice vintage speakers, JBL, Altec, Jensen, CTS, Utah, Ampex/JBL in 8, 12, and 15's.  Have a few decent cabs in differing configuratins.  Benefit of all this crap is to know how tone is made and how to change it in the various ways possible to get a certain result with that given shop of tools.  So tubes are a part of the picture, not as important as the output transformer, that has more effect on tone, it's just a pain in the butt to change out every few minutes for another one to hear the differences...

In my Ceriatone/Marsh Overlord FSX-50 OTS  here is my list:

For V1, I wanted a tube with a tendency to generate lots of harmonic content, both odd as well as even and quiet for microphonics.  So I went Euro with a Canadian made Electrohome 12ax7a/7025a, the Canadian made and superior version of the 12ax7 shortplate Amperex "Bugle Boy" tube.

For V2, I wanted increased harmonic content, with no mud on bottom, yet fat and warm sounding at the same time.  A Raytheon JRP 12ax7 long blackplate with rectangular getter halo deliveres more of the fundamental note in it's tone and harmonic content, this will complement the Euro 12ax7 tendency for expressing more odd order content than the American tube.

For the PI, I chose a Siemens e83cc with closely matched sections.  This is the very top of the line for the Philips family of tube manufactureres, exceeding even the famed 10m Mullards for build quality as well as tone, I have both. 

Rich, full, sustain-y...

Power section:  6l6gc Sylvanias matched within 1/2mv @ 38mv bias. or 6bg6ga with adapters, biased at a similar amount, not as tightly biased, more like 3mv apart. 

This amp is very big, fat, and in your face with the Lift Negative Feedback switch,  goes from creamy to face ripping Marshall tones dependeing on which way that switch is facing and the OD trim setting.  Doesn't need a lot of OD trim or gain to be really agressive with LNFB.  This amp sounds better without the C-lator. 

For the C-tone 50w HRM/c-lator, I went totally  bonkers and got what I wanted, a Euro sounding el34 amp but having the smooth D-style oozyness of note flipping and singing overtone-ics. 

For V1, I chose an Adzam 12ax7s, a very rare Euro tube with very complex and abundant harmonic structure, with upper mids, top, and presence detailed like a silverplate mil spec Mazda 12ax7, (!!!) that is to say, abundant and sweet, and reasonably resistant to microphonics.  This tube, like all tubes in all sections of the preamps in ALL of my amps has to win a shootout among similar types to fill that spot.

For V2, a tube that will take what V1 hands it and turn it into monster sauce, I chose a Blackburn Microtech E813cc, a 12ax7 variant that was  a factory sample given to me byu the rep.  It is specifically designed to be placed in v2 and cathode follower stages in musical instrument preamps.  It is from what was the original Mullard factory in England.  The restart failed as a business, but the 10,000 hour rated tubes do their job well enough to win the shootout for that spot.

For the C-lator, now the V3 position, I chose a Siemens longplate 12ax7, this tube wants to sing and sustain like few others, in the class of the telefunken smooth and ribbed plate for delivering that wonderful overdriven violin sustain sound, along with a propensity to deliver the most amazing harmonics in volume swells.  These are microphonic as a rule, but this position is not as critical as V1.  No problems exist from microphonics.     

For the PI, I chose the Siemens e83cc in tightly matched sections for the same reasons as above.  Again, this tube won the shootout for its spot. 

Power tubes are a pair of tightly matched RFT/Siemens  el34's, matched within 3/4 of a mv, 37mv.  These tubes are warm, fat, and love to sing the british blues.

I am contemplating an OT swapout in this amp for a MM Radiospares enhanced model OT like in my Siegmund Midnight Blues for its' amazing harmonic content and clean tone gorgeousness.

[plasticvonaband]

It would be interesting to see if anyone tried KT66 or even KT77 output tubes. The latter apparently are a mix of 6L6 & EL34 - should be a great fit with the Bluesmaster. 

User JD0X0 has done alot of power tune testing in his OTS and settled on KT-88's. Yup that's not a typo, KT-88's search for KT88 or KT-88 in the overtone forum. He describes all the attributes of the power tubes he tested

Gregg

[bigwebb83]

Well I got some TAD 6l6's in as well as the nos rca short plate for v1 as suggested by another member.  Popped them in and was disspointed.  Then I remembered to check the bias.  The amp was way cold so I dialed it in at around 38-39ma and gave her another shot.  I can't make a full report yet because the wife was napping but I can say I am excited amp warmed way up and the clean channel and od sound awesome.  Much tighter bass.  Will report back later with more details

[plasticvonaband]

i actually went back to the TAD shorties after one of my 6L6WGB's red plated (it was only a matter of time). Had to switch V1 and V2 out, though. With the long plate GE in V1 and the JAN 5751 in V2 it sounded very dark and uninspiring. Put Telefunken's in V1 & V2 and voila much better! 

Gregg

[Tahoebrian5]

Alright, I need some help. My hrm 50 is almost done, just waiting for my trannies to show up. I need to order some tubes now. Can some recommend which tubes to get as a starting point? After reading some of the above posts I realize I have no idea what I'm doing, haha. I guess I have to start somewhere. As far as tone I'm not really sure. Id like the clean to be touch sensitive and I like harmonic content.. Um, for the overdrive singing lead tones but I don't want the rythym to sound too thick. Anyway, a recommendation and place to order would be awesome!! Thanks, B

[plasticvonaband]

you really can't go wrong with the stock JJ's to start out with the baseline and tweak from there. After all, it's what Nik builds the amp around 

[SoundPerf]

I have the TAD 6L6 WGC STR's and find them in simple terms to be a very solid sounding tubes that are very similar to what a very good 6L6's should sound like IMO.  They also seem to be holding up well. The preamp tubes are probably a harder thing to narrow down. As far as production tubes, I used Tung Sol's, but, I hear good things about others too (Mullards, Shuguang) JJ's are very good tubes. I find them to be a bit too gainy for the most part for certain applications. I think that Nik probably sticks with them because they are the most predictable and reliable from batch to batch and probably gets a really good deal, price wise. Consistency is very important to a business. And like I said they are good tubes.

Then there's NOS. It's worth a try to get some preamp NOS and see what you think.

Like Plasticvonaband (Greg) said, I would start out with a good set production tubes to get a good baseline. Preamp NOS tubes won't completely break the bank.