I have one and gig with it alot. It sounds great and so far very reliable. I typically use only the tube preamp but you can switch to the FET pre or mix both together. A great all round amp IMO.
Well, this head is everything anyone could possibly want. Leaving the EQ settings flat (12 O' Clock) gives you an astonishingly pure tone, and cuts through music extremely well. I've owned heads from Behringer (BX4500?), Gallien-Krueger (RB1001II), and Peavey (VB-2 all tube), to an all rack mount set-up($1500 of button pushing and knob turning glory)... and to be honest, I love this head the most. I would never go back to any other set-up because this head has it all, and it's very straight forward. You don't need a million other rack-mountable effects to help the sound coming from this head, you just need a bass, this head, and a cab. It doesn't emphasize on bass, mids, or treble any more than one another (unless you set it that way ). Simply put, if you can get your hands on this head, do so. It's relatively cheap, and produces sounds that you would expect out of a $1200 amp.
It's a great, versatile, loud head. Plenty of tonal options, tons of "dialability" between the eq and the adjustable filters, and solid as a rock. Great head.
Does anyone use one of these with an 8 ohm cab? If so, what cab and does it seem loud enough for medium-sized rock gigs? What other heads would you compare it to as far as real-world power output?
I have a 750 and it's awesome - can't imagine that the 600 isn't about the same with a tiny bit less power.
A Genz-Benz and a Mesa Boogie will do any tone that you could possibly want. The Genz excels at the quicker and more pure bass tones, while a Mesa does the faux-pure-tubey-goodness. It's one of the most versatile amps on the market, yet setting it flat makes your bass sing.