Orange Amps Forum

ardent, what cabs are you running....12's or 15's??

That Fender Jazz is sweet too.

I've found this thread to be very informative. I'm also pondering putting in a new set of power tubes into a AD200 Mk3. Some years back, I made the KT88 for 6550 swap on a Sunn 200s and was quite pleased. (As well, I'm following Bassdrop's lead on the preamp tubes.)

But I'm pretty much a lightweight so I'm not raising this to start a fight, only curious. A while back a gent who runs a Marshall repair/modification shop warned me off of KT88's in a monster Marshall head we both own. He said "The amp runs a real high plate voltage so don't try to use any ole tube. I have GE 6550's in mine. It ate a rack of KT88's once."

Does this make any sense?

Thanks!!

Happy- That does make sense since there were some amps that subjected there tubes to serious punishment in order to maximize clean power. One of these was the Fender 400PS:
http://www.timeelect.com/6550a-ex.htm

For a while now, the real-deal NOS KT88's have been extremely high priced so it could have been a comparison between the GE's and the new production "KT88s" at that time. The Chinese versions especially for years were horrible quality and have only recently improved.

Thanks Bassdrop. I bet that explains it.

BTW - do you remember that a 400PS was on Ebay within the last year? Had a BIN around $700 and had no takers in the first round. I briefly pondered it just because it was so nasty. But that article about how hard it is to bias or just generally tame put me off.

what was the consensus on which tube was more reliable and able to take the punishment? kt88 or 6550? Ive desided to go with Winged C's but I can decide which model is going to last longer.

My response was basically that there is not a solid consensus, but that theoretically the KT88's should be tougher but depends on which manufacturer you go with. As I had mentioned in one of the many threads you started, I've heard better reviews of the New Sensor reissued Gold Lion KT88's than any other current production type. If you were to look for higher quality you would have to look into some NOS types like GE 6550A's. Mine are just starting to get a little weak now after having been gigged on every weekend for over 2 years. IMO, that's a bit better than what you would get from current production 6550's or KT88s. From there you'd jump significantly to the NOS giants of the 6550 family, the original Tung Sol 6550 and MOV Gold Lion/Genalex KT88. You'd be paying about $1000 per quartet for the former and upwards of $1400 or more for the latter.

Im thinking Ill try the Wing Cs but I cant decide if I want 6550 or KT88s:oops:...
I would like a set of Gold Lions but at $125 a tube I cant afford that.

The reissues are less than half that price at Doug's Tubes.

thanks for the heads up...the Sovtek 6550s are only 100 for 4...

If you're looking in that price range I'd also check out the EHX 6550, Tung Sol reissue 6550 (another user on the forum recommended them a while ago), or the Winged C. It's worth the extra couple of bucks to buy through a reseller who thoroughly tests and burns in their tubes.

New Sensor Tung-Sol 6550 or the Electro Harmonix 6550EH...
which one would you guys use?

www.watfordvalves.com do a pretty good selection of valves and their cryo treated ones sound great