Wow, so I have had this for a while, and have been playing around with it at home, but I just had the ability to my first band practice with it (just drummer, and I). Wow. Im not sure if there is a solid state section of the preamp, but there isn't an abundance of gain to this, and the gain it has is more of a slap then a roll-of-quarters-in-the-fist punch that high gain amps have, but still very usable (I needed a boost, but this can be said about most amps, even high end amps). Sound I am running this through my Hughes and Kettner cab, with g12f-60s in them (Think of a V30, with the spike at 800, but still having the low end "weakness" to them). At band volume (which was only half way on the volume dial), it gets very dry, lower gain Mark IV tone. The head itself was running at ISF 7/8 (british), Highs 5/6, mids full, bass at 3/4, gain at 5. I had my TS-9 running with gain at 2.5/3, tone at 7/8, and level at about 9, and an MXR 10-band eq runngin with a slight boost at 1khz, and 4khz. It had the bark and the punch-yness of a the Mark IVs I have heard, but didn't have the rich, bubbly gain. With the gain any higher, it started to saturate (good) but became discernable (bad). ISF Control The ISF control adjusts the whole tone stack, not just the mids, which is what I was expecting. To my ears, it played with the controls as Highs 0/American 3khz 10/Brit 5khz Mids 0/American 500hz with a sharp bell/notch 10/Brit 800ish, with a wide bell Lows 0/American 70-80 hz 10/Brit 100-125hz It seems like there is some compensation going on too, highs and bass seem to effect the placement of the mid spike. As well as, with everything on 5 and the bass at max, it would become overwhelming, but once you start adjusting, more highs, less mids, the bass seemed to move around/position itself where no matter how low you had the mids, they wouldn't dissappear (read as "no black metalz") I guess it does emulate 6l6 on american, and el34 for Brit, but not overall realistically. I really couldn't find a tone for the American side, but then again, I have a very mid heavy cab, so the sharp Brit sound really doesn't hurt. This thing is a 6/5 just for price alone. THIS IS LOUD ENOUGH TO PLAY WITH A MODERATE SIZED BAND! I bought this with the expectations that 5 watts is roughly 35% of 100 watts, so i should be able to crank it all the way up and at least still be able to hear myself. I had this on 5 and it was loud enough. Maybe in a 6 peice, 2 guitars, bass, drums, keyboardist, and alot of layer stuff, this might not cut it in practice, but I dont see how unless you are dialing it way out (scooped mids, max gain, max bass, ect). All I have is my cellphone, since my girlfriend is doing an internship in PA. Here is a video of sloppy master of puppets intro This was at lower volumes (enough above acoustic string sound) and the phone was about 2-3 feet away from the cab. The lows aren't really in there, and the highs are misplaced and brittle compared to the room tone, but you can hear the mids/barkyness. I think it hits in the general area of the MOP tone (I think it was marshall, and a Mark IIC+. Whatever they used ).