It would have been nice to see a comment on the widely varying weights of heads with similar complements of tubes. Why is the Diamond 14 lbs. heavier than the Carvin? Bigger transformers?

Also, I have to take issue with the comments about the Line6 HD147 regarding volume, when it's Db level was higher than some of the others. I have one I use as a practice amp. It's way louder than my Marshall 6100, JMP1/9100 and my Boogie MkIIB. It was replaced early on though when it seemed underpowered. I had noticed a low-level, siren-like whining coming from the head, probably a fault in the switching power supply. The replacement is as loud as you'd expect from 300 watts.