Yep, I agree with Dgarretson. I had a Premier 140 with the stock EB 6N30's and bought a pair of DR's. There was a small improvement in bass and dynamics, but I heard far greater changes with various 6922 input tubes and with output tubes such as NOS Tung-Sol 6550's. If you really want to hear what this amp will do get some NOS T-S 6550's and forget worrying about the 6N30.