A couple of tube questions please.

[MK IIB]

A couple of questions.
Can anyone tell me what make of tubes these are please?They're labled Peavy.

They were in my Mark 2B when I got it.
There were a pair of these 6L6's in the bottom of the amp.

I took the EL34's out and put in the 6L6's and the amp's fuse blew.Do you think it would have blown the 6L6's with it?

 

[JOEY B.]

Those are Peavey labeled Sylvania 6CA7's . Sounds like one of the 6L6's that was in the bottom of the amp may be bad. They are also Sylvanias.

 

[MK IIB]

Thanks Joey.
How would these EL34's sound in a Boogie mark amp compared to the current STR 440 6L6's?It's not simul class just a 2 x 6L6 60 watter but it has bias pot added!

 

[McBarry]

Rumour has it that Mike B /Randall had the Sylvania 6L6's specifically in mind when designing the Mk II series.
For me, it's a no-brainer - they positively make my Marks sing sweetly.
And can take a batterring too - I've seen awful voltages on servicing and they come back for more.
My Marks all live in road cases but I know they can handle a bit of rough handling too - within reason of course...

Re specific sonic differences vs 440's - try some and see..
But tube rolling can be addictive.. LOL LOL

 

[MK IIB]

Hi Dave.
I was talking about how the EL34/6CA7 would sound in the Boogie.I never got the chance to hear how they sounded and the amp's now been biased for 6L6's.
Regarding the Sylvania 6L6's,when I put them in after taking out the 6CA7's they made a loud hum and blew a fuse so I'm scared to put them back in incase they are shorted and take something out with them?

 

[stokes]

Yeah,one or both of those tubes are shot,throw them away.

 

[MrWhoever]

Honestly i would keep them. Its likely only one failed, if you are lucky there is plenty of life in the other one left...to me that is a big advantage of your 60watter, you only need two sylvanias, which are really really nice in your boogie. Maybe one of those days you stumble on another single one. Those are all mesa selected and the tolerances were not as big then, no color coding for example. Maybe spending real money on another one would be a stretch, but if you get one cheap i personally would at least try two slightly mismatched sylvanias. In fact i have a single spare that i am holding on to myself..

 

[stokes]

Yeah,it may be worth keeping one,but which one is good?I have test gear to figure that out,but not everyone can.Just how good can you expect the "good" one to be?They are very hardy tubes,as are most old stock tubes,but if one of a pair failed,presumably from old age,how far behind is the "good" one?To find another one that is a close enough match,it would have to be just as well used as this "good" one you salvaged.