What tubes do you use in your Mk IV?

[yngzaklynch]

I just talked to my favorite tube supplier and he recommended the following tubes. Said many Mk IV owners really liked this set up.

v1 - Tung Sol reissue
v2 - high gain JJ or sovtek 12ax7lp
v3 - shuguang 12ax7c9
v4 shuguang 12ax7c9
v5 balanced shuguang 12ax7c9
Also got some SED 6L6s

Can't wait to try them out.

 

[brianf]

EH across the board!!!!

brianf

 

[yngzaklynch]

EH across the board!!!!

brianf

Even in the power section? What do you think of using EL34s in the outer slots? I had that in my first Mk IV and think I might prefer that.

 

[scottywompas]

I have GT el34's in my outer sockets. I love the sound. I was pretty happy with the 6l6's there but the el34's are the sound I'm looking for.

Scott

 

[Antoine]

All Ruby 12ax-7 new generation Chinese tubes
4 STR 430 Mesa-Boogie 6L6's

i really want to try the 6L6's/EL34's combo, can someone explain the difference, tonewise, on the 3 channels between 4 6L6's and the 6L6's/EL34'scombo ?

 

[Russ]

I have been swapping Mesa SPAX7s and 12ax7(Russian) and GT: Gold 12ax7C and Silver 12ax7R. I have also been swapping 1963 GE longplates and 1960 RCA longplates. Yet still I have also been swapping 1962 Mullard shortplates and JAN Phillips. Another random EH has also filed through.

I find it difficult to stay put. I feel that V1 and V2 are the place to see the characteristics of the tubes best but only at low gain can you really appreciate the vintage stuff. I have been preferring the GT gold in V1 and the silver in V2 for high gain with the SPAX7 filling the rest of the bill. I don't care for the SPAX7 in V1 and V2 as much. It could be because hte GT tubes are just higher gain and faster rise. I found the SPAX7 rather dull.

I do not have the Tung Sol reissue or the JJ to compare. The SPAX7 is supposed to be a WC which is supposed to be close to the LPS. That said, I would hope that the Tung Sol is better. I have heard the JJ to be dark but good in high gain apps. Depending upon what the Tung Sol sounds like, I would assume JJs straight through. I have been seeing quite a few people that tend to like the JJ. I don't have any but would like to see what they sound like. Most of my stock are either bright, full, or dull (SPAX7). I remember hearing about success of Tung Sols in Fender and Ampeg amps. It might be the way to go if it is an articulate tube for V1. I know I lke the old stuff in V1 as long as it is clean to mild/med gain.

I have a set of EH EL-34s in my JMP that I want to swap into the outer pair but I have to find my old set of EL-34's (3 of 4) from a former 100 watt Marshall that were either Teslas or Seimens, I am unsure what they were (it was 10 years ago), so I can slap them into the JMP. Even at the cost of a rebias on the JMP, I would like to hear the EH in the MarkIV. I also have a matched pair of 1960s GE 6L6GCs sitting around that I would like to swap in. The current 6L6s in my MarkIV are 6L6GC 420s.

Anyone ever try old GEs?

 

[Antoine]

I have a matched quartet of 6L6's GE too, i 've mounted them on my MarkIV and it was pure magic they have a fantastic sound very clear with a huge low end that stay focused ! since then i keep them carefuly and only mount them for specific occasions (studio work) !!!

 

[Antoine]

I have a matched quartet of 6L6's GE too, i 've mounted them on my MarkIV and it was pure magic they have a fantastic sound very clear with a huge low end that stay focused ! since then i keep them carefuly and only mount them for specific occasions (studio work) !!!

 

[Russ]

I might have to sit on these GEs then

 

[Antoine]

Russ, be sure these GE have the correct bias first !

 

[Russ]

I didn't think it would matter much with the fixed bias as long as I didn't crank it too loud for too long. What should hte bias for the tubes be as far as Mesa is concerned so that I can go have them put on a bench? I would hate to put them in and check the bias on them in the amp. Besides I would need one of those Biasrite things anyway.

 

[brianf]

EH across the board!!!!

brianf

Even in the power section? What do you think of using EL34s in the outer slots? I had that in my first Mk IV and think I might prefer that.

Yup in the power section too. And yes I have had EL 34's in it from time to time. Also EH.

brianf

 

[Toh]

i really want to try the 6L6's/EL34's combo, can someone explain the difference, tonewise, on the 3 channels between 4 6L6's and the 6L6's/EL34'scombo ?

I'd like to know it too.
For the moment, my Mark IV is loaded with four JAN Philips 6l6 in the power section, four JAN 12ax7 and one Ruby 7025 in the preamp. The clean is wonderful, but the lead could be a little nastier and perhaps fatter. Do you think EL 34 would help ?

Or should I change the preamp tubes ?

I'd like to get closer to the sound of a Fuchs or Dumble ODS..

 

[brianf]

To tell you the truth putting the EL34's in the outside does not make a huge difference untill the amp is really at high volume.

It has a bit more distortion. It's hard to generalize because different brands will have a different effect. I can only comment on EH and Winged C's.

Just buy a couple of different brands of EL's and experiment a bit.

brianf

 

[Russ]

Sounds like you have a nice tube complement right now. Sometimes you get to that point of diminishing returns and there really isn't much better without spending a lot more money for not much more satisfaction.

GAS....

The quest for your own holy grail tone can be eternal....