Mark V Tube Swap

[XxDAVIDxX]

So I want to try EL's in my Mark V but I don't want to buy a set of them just to "see" how it sounds. Well my Marshall has a quad of EL34's and I'm wondering if I could jank'em out and try them in my Boogie. Good idea or bad?

 

[audiotaxi]

You can't really do any harm, but bear in mind, the bias won't be optimized, and you can't adjust it, so you may be disappointed in the tone as a result. I put JJ EL34L's in mine recently, and have been very pleased with the result.

 

[XxDAVIDxX]

Thanks audiotaxi. I'm a big fan of EL34's although I love my Mark V, I'm very curious to hear the difference they will make. I've heard the YouTube clips but I wanna hear it for myself. Guess I'll call tube depot and try it out.

 

[audiotaxi]

Ya I know, I've been trying to get into the Marshall ballpark (I know I know, guys are thinking "buy a Marshall then), I had a JVM back in the UK, but when I moved to Canada I got such a deal on the Mk V I pulled the trigger on it. Can't afford the luxury of a second amp unfortunately.
Like I say, to my ears, the 34's have been a worthy "mod".

 

[INDI]

You can't really do any harm, but bear in mind, the bias won't be optimized, and you can't adjust it, so you may be disappointed in the tone as a result. I put JJ EL34L's in mine recently, and have been very pleased with the result.

Mark V has a bias switch on the back. Adjust it accordingly for any tubes are on the amp. Read the manual - page 43.

You can't mix EL4 and 6L6 though, as you could on MK4.

However, from what I have read on the internet about proper tube biasing, it might be possible to mix 6L6's (tubes 2 & 3) and EL34's (tubes 1 & 4) and set the bias switch to 6L6 position, NOT EL34, as this would wear out the 6L6's. However, the bias for 6L6 has not enough current for EL34's which would need more, so the EL34's won't work within specifications; yet they won't break. The other way around is dangereous. Probably, if you run the amp in 10W or 45W it would be even safer. If anyone has an input on this, or tried this, please share it with us. I would buy 2 EL34's just to test the sound.

 

[Scary]

Buy the tubes when you get money. I have the 450's and obviously they're great. Hopefully other el34's sound near as good.

EL 34's sound different and most of the time I like them better, but the 6L6 have a chainsaw grind to them and more bottom end.

 

[Jedro]

Don't worry about biasing or any of that. Just make sure the bias switch is on the proper setting - and change it back to 6L6 when you put the 6L6s back in.

Otherwise, pop those suckers in! I've run EL34s since I bought my amp, never even tried 6L6s with it. And, Ive had Mesa tubes, Groove Tubes and now I'm running JJ E34L tubes and can honestly say there isn't a huge difference to worry about. The JJs sound a little smoother in the top end, but that's about it.

And yes you can run a 6L6/EL34 combination but there are limitations to the wattage settings you can use. Damaging your amp with a flick of the switch doesn't sound like a good idea to me. Pick a tube and a sound a go with it.

 

[INDI]

And yes you can run a 6L6/EL34 combination but there are limitations to the wattage settings you can use. Damaging your amp with a flick of the switch doesn't sound like a good idea to me. Pick a tube and a sound a go with it.

Could you explain a little about this?

 

[audiotaxi]

You can't really do any harm, but bear in mind, the bias won't be optimized, and you can't adjust it, so you may be disappointed in the tone as a result. I put JJ EL34L's in mine recently, and have been very pleased with the result.

Mark V has a bias switch on the back. Adjust it accordingly for any tubes are on the amp. Read the manual - page 43.

The OP was asking about whether he could "yank out" the EL34's in his other amp". Yes he can, and of course you can flip the EL/6L6 switch. I read page 43 before I put in my EL34's :lol: The point I was making was that the EL34's he yanked out may not meet the bias specs hardwired into to Mark V, and therefore wouldn't be optimized. It wasn't clear whether he knew that.