18Watt.com

Didn't to me either!!! It was a BF Super Reverb that had sovtek tubes throughout and when I replaced the rectifier tube it just woke up!

It worked before... not like the sovtek GZ34 was bad or anything.

^-Will that rectifier tube replace an EZ81?

GZ34 is an octal rec tube.

^-Oh, that explains it

The one on the bench now has 2x 5751, 1x 12AT7 and 2x 6V6

Cheers!

sovtek 12ax7, JAN 5751, EH84's, 5y3 sovtek

Well, in my 18 watter i got from Loverocker i'm running POLAM EL84s, a Brimar ecc83 in V1 and a Mullard cv4024 in the PI. I'm happy. The only better combo i had was putting in a new shield Mule in V1. I'm saving that for my JTM 45 build though.

Simple answer, "Whatever I"ve got!".

I'll list a few and my impressions of them (so far). The cork sniffin' continues:
Tung-Sol 12ax7 -sounds good , very gainy in first position. Mine happens to be terribly microphonic.
RCA NOS 5751 - great in V1. Tames the gain.
EHX 12ax7EH - nice and well behaved.
RCA 7025 - I like them in all positions
Sylvania 12ax7a - ditto
EI 12ax7 - haven't tried in the 18watt as yet
Realistic Lifetime 12ax7a -looks very suspiciously like an RCA , Sounds like it too
GE 6189 (12au7) havent tried
GE 12at7/ecc81 - ditto
Realistic Longlife 12at7 - ditto
Unknown 12ax7 (probably a Silvertone , because I used to have one years ago) the writing is rubbed off, long grey plate - haven't tried yet
Made in China 12ax7 - untried
El 84's
JJ - bright , clean
Phillips (old and used) - a lot like the JJ
TAD- punchy not as bright or clean

6V6 ( yep it's a TRinity SIII V6)
Raytheon ( Made in England) -good stuff, creamy
JJ - They seem a little more brittle than the Raytheos but still nice
EH - not as brittle as the JJ , good and crunchy

Now remember , Kids. You must try this at home. Especially since my ears are shot from too much abuse through the decades, and they happen to be pasted on MY head. Yours will prolly give different results , as they (Hopefully) are planted on the sides of your noggin.

Good luck in your sniffin'.

LeeMo

I like to use tubes with lots of vacuum inside. Preferably NOS vacuum....

My 18 tmb with boost(a la Plexi) has a mullard V1, v2 and v3 are tested mesas speced in by Plexi, Tesla Rosnov EL84s and a sylvania ez81. I have a mullard ez to swap in but not sure if it will do anything. I have tried telefunkens in V1 liked em, all sorts of americans, i have a high gain sylvania that makes things abit bright but kicks with the neck bucker! As far as ELs go I have some mullards, Polams-havent tried and Saratov 7189s havent tried. I really like the Teslas tho. Very hearty and breaks up nicely ymmv

After much, tube swapping, I've settled on V1-mullard ecc83,V2-RCA 5751,an old sovtec 12ax7 in V3(only thing that worked for the trem,and remarkably very nicely ) El84's are Polam Telams, and a NOS Tesla EZ81,This set up works great for me!
Pigman

My TMB has:
V1-Golden Dragon
V2-Tungsol
V3-JJ
Power-I'm rotating a pair of Ei's(My favorite), Jan Phillips(Idetical to the Ei's) and a pair of TAD's.

The TAD's have the most head room and are physically larger/heavier than either the Ei or Phillips.

I was running two ruby/chinese 12AX7s and two JJ EL84s with a Tung Sol 5U4GB in my Lite IIB.

I was feeling a bit down on the sound of the amp, especially the cleans, they seemed less good than they were in a previous build of this amp, and i was thinking it was the new trannies or something else related to the rebuild.

Then i remembered that i wasn't running these tubes before. I have a very small collection of old tubes lying around, so i sorted through them to try something else out. I swapped in an RCA 12AX7 in v1, a slightly cranky(microphonic if in v1) Tung Sol in v2, and then a pair of Sylvania 7189s in the place of the JJ EL84s. I left the Tung Sol 5U4G in there as there is nothing wrong with it at all, it was basically NOS when i got it with a pile of otherwise useless oddball TV tubes.

Well, that did it. The thing is slightly less gainy(and also less fizzy when cranked) but the cleans are sooo much better, cooler, sparkling, edgy that it is silly. I swapped one of the chinese 12AX7s into v2 and didn't notice a huge difference(maybe a little more gain/punch) but these 7189s are great! I want a pile of them! And they are good for 400v on the plates! So i can swap a GZ34 in and not redplate, if i feel so inclined.

I just wish i had money to support this habit. Clearly some of the old tubes are superior to some of the new ones. On the other hand, for harsh violent high gain sounds, the new tubes seem to have an edge.

For now, the old tubes are giving me the noise i like.

-chris

right now...

JA 18watt tmb

v1 - jj ecc83
v2 - raytheon NOS 12ax7
v3 - sovtek 12ax7
v4+v5 - Tesla EL84s

The Raytheon is a beautiful tube. Delivers a warm and 3d tone. sweet!

You are missing out on the best bargains out there. I'm using a pair of NOS Sylvania blackplate 6GK6, professionally matched by a reliable dealer. Articulate is how I would describe them. Of course, you've got to do a bit of rewiring, but heck, if you are a builder, this is about 5 minutes work. I've got a nice set of 3 GE used 12AX7's. Been thinking about rewiring for some Mullard 6EU7's but I've got them sounding good in the JTM45. Also, I've got a NOS RCA 6CA4. I bought a used GE branded Mullard rectifier, but the plates rattle, so I pulled it. It was an inexpensive tube -- live and learn. Think out of the box!

In my Voxwatt:
V1 Valvo Ef86
V2 Siemens 12ax7
V3 Ge 5751
Pope Ez81
National GZ34
Sylvania El84

zaphod_phil wrote:

tarzanalog wrote:P.S. The single greatest change I ever made to one of my amps was putting a metal base Amperex GZ34 rectifier in it. Like taking off ear-muffs... no lie!

Does not compute.

If a different rectifier results in different B+ it can have a signifigant effect on sound. Just experienced with my 36watter.
6 months ago my house got new "service/meter" from the pole and things sound different.

Cathode_Ray wrote:

zaphod_phil wrote:

tarzanalog wrote:P.S. The single greatest change I ever made to one of my amps was putting a metal base Amperex GZ34 rectifier in it. Like taking off ear-muffs... no lie!

Does not compute.

If a different rectifier results in different B+ it can have a signifigant effect on sound. Just experienced with my 36watter.
6 months ago my house got new "service/meter" from the pole and things sound different.

That's the experience I had. I just put the Amperex in my 36W and it happened again vs. the JJ rectifier.

BTW - along with that rec tube I've settled on this tube compliment in my 36W TMB EF86:

V1 - Sylvania 6267
V2 - TS RI ECC803S
V3 - Realistic MIJ 7025
V4 - Mullard CV4024
V5~V8 - Sylvania BP 6BQ5

It's sweety and punchy... and thick and juicy... all at once! I'll get some clips up soon.

We know that tone is very subjective. What sounds like "pulling a wet blanket off the speaker cabinet" sounds like "ice pick highs" to the next player, etc.

IMHO, I think that amp design is the BIG determining factor in whether currently produced tubes sound "good" or not. I know that some designers voice their products around certain tube brands/country of origin so they sound good with what's readily available. For instance, Jeff Bober of Budda Amplification designs his EL84 amps around Russian Sovtek EL84's with a Sovtek 12AX7WB in V1! Most here conclude that those tubes are not the best choices today but to my ears those tubes indeed sound the most balanced and fullest in a Budda to all the other currently produced choices. In fact, I put a Telefunken ribbed plate in V1 with high hopes and it sounded thin, harsh and brittle.

So when I buy tubes for my Budda Verbmaster, I just get Sovteks and save money.

OTOH, I agree that NOS works best for a stock 18 watt.

The Balls Amps 18 watter was voiced to sound good with current production tubes though.

Marshall 1974X

V1 Tesla E83CC
V2 Tesla E83CC
V3 Siemens & Halske ECC83
V4+V5 Mullard EL84
V6 Mullard EZ81

After many trials with other tubes (Telefunken EL84s and ECC83s, Sylvania JAN 12AX7WA, etc.) I found that these combination sounds best to me. I also changed the speaker to Celestion G12H/75Hz from 1972, because I like to have the full spectrum from light OD to high gain which the stock G12M Heritage (and the stock JJ EL84s) doesn´t deliver.