Pulling a matched quad for testing

My friend wants to re-tube his ENGL Powerball and it occurred to me that I could take one quad of my Winged =C= 6L6s for him to try them and see how they sound.
(I wouldn't be using the 2:90 with nothing in the sockets of course, I'd use my other amp)

Can running the tubes in a differently biased circuit damage them or shorten their tube life considerably? His amp is biased REALLY low and my quads were matched for the 2:90, so I don't want to screw anything up in terms of the tubes' current draw.

Your =C= quad was matched so all tubes were within one tight tolerance in a certain range...Basically one tube was the "master" in the boogie range and all three others were selected to be real close to that master tube.

Running this quad in the Engl won´t damage them. You can even take a bias probe and adjust the amps bias to this matched quad.

OT: Try a quad of Tung-Sol 6L6GC-STR in the Engl....pure magic!! Especially the midrange complexity

Thanks! Kind of what I suspected but it's good to be sure

Triaxstasy said:

OT: Try a quad of Tung-Sol 6L6GC-STR in the Engl....pure magic!! Especially the midrange complexity

Click to expand...

Actually, that is the tube that my friend will be buying, but he wants to try the =C='s as well before he shells out so he won't feel like he didn't give them a shot

They are expensive, =C='s, yeah but IMO, as I've said a billion times, best current production glass, period. 8)

Just be sure to set the bias in any amp properly when installing different output tubes. :idea:

Yep, will do, of course. Not sure what you mean by "different" output tubes, though the amp has 6L6s and we'll be replacing them with 6L6s; you have to bias anyway. The process is slightly tiring though since it has no testpoints :|

By "different", I mean any output tubes other than the ones currently installed, whether new or used. There are exceptions to having to check the bias with a change in output tubes, which would be if you used the exact same tubes with the exact same rating, such as when installing the second pair of a matched quad where the first pair of the quad had been installed and biased, or using GT to replace identical GT, or Mesa to replace identical Mesa. However, I always check the bias when changing output tubes anyway, just to be sure that they are really matched and function properly.