| We have used both types in the Trace heads. We constantly monitor tubes, so it's whoever has the all around best tubes at the moment.
When looking at the front of the amp, the tube on the right side drives the power amp. On the AH1000-12 and 1200-12, we check to make sure that the tube is balanced so that the power amps are balanced. Obviously, this is not really an issue on the 600-12. I wouldn't go out and buy a snake oil tube or anything. You just don't want the halves of the tube to be way different. This tube is always in the signal path, so we also use a low noise tube.
The tube on the left is for the tube overdrive, so it switches in and out. We use a selected low microphonic tube for that one for lowest noise and so it doesn't squeal.
These are things to keep in mind if you want to swap tubes.
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Every bass player has to own a Peavey at some point,
you might as well get it over with. -seanm
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