Mark IV tube placement...

[Daxman73]

Hey guys and gals, I have a pre-amp tube placement question regarding my early Mark IVb...I have a Mesa SPAX7, Tung-Sol, Svetlana and a Mullard reissue...I was wondering what order to place these in...I like lots of usable gain with clarity and definition, with a singing lead tone, but tight rhythm tone...Asking too much, yeah I know...I play in an original band that plays covers in the vein of rock to metal...I am the only guitarist, so my tone has to count...I know this has been asked before and I know that tone is subjective...I also know that experimentation is always best...I will do that, but I'm looking for a good starting foundation with the tubes I have...Any help would be greatly appreciated, thank you.

 

[mejoshee]

check the mesa/boogie page for the mark iv user manual. i think it's pg. 17 of the manual that has the tube layout for the chassis.

v1: spax7 always. this needs to be the quietest tube since, as they always say, this is the first stage of the amp and noise will be amplified throughout the rest of the stages. the tung-sol might also be good for this since these are relatively well made. but since the mesa tube is meant for that, you might as well use it for that.

v2-4: kind of up to you, so you can probably put them in any order you want, though probably v3 or 4 should be quieter as well because it's the high-gain stage and reverb, so maybe the tung-sol in either. i would keep the svetlana as late in the amp chain since they're generally a little noisier.

v5: matched & balanced phase inverter. doesn't really matter what brand on this one, but durable is always better so choose a brand you trust. don't know if you plan on changing this as well, but that's what you should aim for if you're retubing the tubes of unknown age and wear for the whole amp. v5 is the one not in the line of the rest of them.

hope this helps.

ps doubtful you will hear a difference with the v2-4 combinations since you're using all of them anyway. this would matter if you were shopping for just one brand that you intended to use for all stages.

 

[marklyn]

The best thing is always try them all. Turn the amp up a bit if you can. Start with V1 with the other tubes that you currently have in there. Mostly you're looking for the Rhy1 tone here. You'll find a favorite. Then try V2 which will impact Rhy 2 and Lead more. After that there probably will be some differences but not as drastic.
I would tend to say the Svetlana in V1 and Mullard in V2 but that would be based on stuff I've done with NOS and not with the reissues.