I may or may not be the only one here who owns this amp, not sure. so this is for FYI.

well, I've decided that the stock Groove Tubes aren't great. breaks up too soon on the clean channel and the lows are flabby. reading on the internet, seems Groove Tubes have a mixed reputation and some (or most) of them are just tubes from anywhere and everywhere with the GT label slapped on them. so I wanted a change.

much to my chagrin, I then learned that there is no built in bias adjustment in the Blues Deluxe amp. the Hot Rods have one built in. which makes no sense since they're almost the same amps. there is even a place on the internet selling mod kits to add a bias adjustment for this particular amp.

rather than doing that, I contacted a local amp tech and took the amp to him. he popped the back and guess what.....there IS a bias adjustment in the amp. I bought the amp brand new 2 years ago, so it was not previously modded by someone else. so either, I got a one off where they decided to add the bias control to this particular amp, or they've decided to start adding them to this model.

just FYI. I knew nothing of adjusting bias for tubes when I bought this amp. if I had known then what I know now and was told that the adjustment was not available, it would've kept me from buying the amp even though the amp DOES have a control.

the tech was hesitant to tell me where to touch the probes due to chance of electrocution. but actually (I found later when I got home), just like in the Hot Rod, there is a "bias test point" on the circuit board, so there should be minimal worry.