5150 integrated quad question

[Fragle]

has anybody used this yet?
i wonder if this is a specifically matched set of JJ 6l6 and kt88 tubes, or if one can just order a pair of each and plug them in?
actually i don't quite see how this could sound anywhere near decent. afaik, kt88s run VERY hot, i.e. need a very hot bias setting. now, iirc the bias on the 5150 is fixed on such a low setting that even the much cooler running 6l6 tubes are biased way too cold. wouldn't that mean that the kt88 pair runs EXTREMELY cold then?

another question linked to the one above: due to the stock bias being ice cold even for 6l6 tubes, am i safe to get any matched 6l6 quad and just plug them in? my fav. tube store is pretty good and allows me to specifically order a quite hot or cold quad. should i ask for a particulary hot one so the stock bias comes up a little, or could this once again possibily damage the amp?

thanks

[JerryP]

Re: 5150 integrated quad question

Save your money. Unless you bias the KT88's up to a proper bias range they are a total waste of money to put in that amp. The screen grid resistors have to be changed to run KT88's in a 5150. FWIW I tried 6550's in a 5150 that was modded to safely use them and it sounded like ass. I've used EL34's as well and 6L6's are by far the best sounding tubes to my ears. JJ, Svetlana, or SED.
Jerry

[Fragle]

Re: 5150 integrated quad question

alright, thanks bro. i already thought so.
so, what about the 2nd question?

[Chuckracer]

Re: 5150 integrated quad question

Jerry's busy getting my Marshall finished up, so I'll field the second half of your question:

Yes, plug anything in there. If your tube vendor can sell you tubes to match an ice-cold bias, great, go that way.
but you really should have a bias pot put in it so you can bring the power amp into the tonal equation...then again, you knew that!

[taxistationary]

Re: 5150 integrated quad question

well, i'm sure you know that in an intergrated quad, both pairs of matched tubes, where ever they are placed, are biased to their specs. so for instance, the KT88's wouldn't run off the same bias circuit as the 6L6's. bob from eurotubes actually made that 5150 of his to have a bias trim pot for each individual tube, so he has 4 bias pots on his amp. cool idea.

[VoiceX3]

Re: 5150 integrated quad question

Ok, here's where a couple guys are going to flame me, but flame away....I've gotten NUMEROUS comments on my tone. Even from VHT and Bogner guys. If you have a 5150 buy the integrated mathced set from Bob at Eurotubes. They are plug and play. I agree a bias would make it even better, but I havent done it and my tone is simpla amazing! Miles and miles of headroom too. If anyone is gonna say "well for that you're going to HAVE to bias the amp" just shouldn't own a 5150. They are biased WAY COLD out of the factory. If you like the tone stock, you'll love the tone with the new integrated set. You can always get the bias trim pots installed on your next tube change.