Michael, one more time: the (single) tube in each of your amps is NOT an output tube. If you want to see if it could be one of these single tubes in one of the amps, then just leave the amps im place and swap the tubes. You'll know quick enough.
If it IS one of the tubes, then have Lamm send you TWO new ones, and keep the old good one for a spare. The tubes are not matched as far as I can tell, but you'd be better off with two the same age and from the same production run.
If it IS one of the tubes, then have Lamm send you TWO new ones, and keep the old good one for a spare. The tubes are not matched as far as I can tell, but you'd be better off with two the same age and from the same production run.