When I bought my original Block Letter new, it had Sylvania's in it. What a beast. Played it straight for a decade. Tried replacing it many times (because of GAS) and it always won out. Even had an SLO at one time, kept the 5150. Same story with most of the big gain amps of that era, that amp always won out. Looking back, was silly for me to eventually get right of it. I had two...the Block and later the Sig (which Paul Cochrane/ Timmy put in a bias adjust) as a backup. So much past gear I wish I had now.halebox":2mdotym7 said:Just picked this up for nothing. These sound great and the loop is good too. I like that is laid out similar to the SLO with footswitching loop as a bonus. This will be a good touring amp that I don't have to worry about. Suprised that I waited so long to pick one up.