EL34's in IIc

[boogieslayer]

has anyone replaced 6l6's in their IIc or + with EL34's?

if so how does it sound?

 

[Elpelotero]

If you have a Simul Class C, then you can safely replace slots 1 and 4 with el34's. Otherwise, you need to leave 6l6's in there unless you install a bias mod so you can bias the amp yourself. El34's make the amp tighter and give it a more biting midrange.

 

[boogieslayer]

this will sound like a dumb question but how do i tell if its a simul class c?

my boogie is a 1983 mark IIc 60/100 reverb serial # 11994

 

[Elpelotero]

If you have a 60/100, it's not simul class. The easiest way to double check is to 1) look at the switch on the back right side. It will say either 60/100 or simul-class. 2) Check the imprinted code on the output transformer inside near the preamp tubes. It will also say simul class.

 

[Boogie Woogie Man]

With all the mods you seem to be intent on doing, why don't you just sell it and get something you want instead ?

 

[boogieslayer]

all the mods?

just talking about changing tubes...its not the end of the world man it will be ok..

 

[ryjan]

I tried a pair of EL34Ls in my mk iv this week and I didnt care much for the sound. I thought it took too much bottom end away and I didnt notice a drastic change in midrange or the tightness that everyone talks about. The mark iv in class a pentode is super crunchy and still has a hell of a punch to it. With the EL34L tubes mixed in simul-class it still was a little too thin for me. However, I'll hold on to them just in case I buy a bassier cab or something down the road. Theyre cheap though so just buy a matched set and see how they sound with your rig/style.