The Voodu Valve has all kinds of sounds, most of excellent quality. I'm in full agreement with other reviewers on the sound quality of this unit. I plug my Jazzmaster into the Voodu Valve and go right into the mixer, using monitors and stage speakers. I don't like carrying big cabinets around any more. But here's some info you can really use if you've got a Voodu Valve. You may have wondered if the tube inside it is really doing anything, or is it just a gimmick. Well, here's the scoop. My Voodu Valve seemed to loose some gain and output recently, especially during the first half hour of so of playing. I decided to check out the tube, as anyone who has used tube amps knows that's where you go first when a problem arises. But how to get at it? This processor must have been designed by General Motors! You have to take out twenty-seven (that's right,27!!!) screws, some ferrel nuts and a knob to remove the jacket from the chassis of the Voodu Valve just to access the tube. Once inside there I found a Sovtek 7025/12AX7 wrapped in styrofoam. I carefully removed it(rock the tube back and forth then pry it out with a small screw driver...there's no room for big fingers in there) and replaced it with a NOS GE 12AX7 I had laying around. Result? Surprisingly less gain and output than the Sovtek. Next I tried a Yugoslavian RCA 7025 thinking this tube must really suck. Wrong again! My Voodu valve sounded better than ever. I then tried a few more 12AX7's in my collection (I work on tube amps from time to time) and discovered that this Voodu Valve is remarkably discriminating as to the tube you run in it. So much for the tube as a gimmick idea; it's definitely in the circuit. Don't be afraid to try some different 7025/12AX7's in your unit if you think it's running out of gas. And believe me, the Voodu Valve does not like just any old 12AX7. Experimentation is the key, but don't put all 27 screws back in between tube changes! Be careful in there. I don't know much about the voltages in this unit as compared to tube amps, but you'll have to be very dainty in the way you handle things when the electronics are exposed lest you turn your Voodu Valve into a useless tin can. When you've got the right tube in this unit, it will do whatever you have the time to make it do.
I use the Voodu Valve at gigs without a backup, and my sequencer is constantly switching the VV's programs and parameters throughout the performance. So far so good after 2 years. However, any piece of gear with one of more tubes is only as strong as its weakest link, i. e. the tube. It will fail sooner or later. It's too bad the Rocktron engineers didn't take that into consideration when they designed this piece of gear. Making the tube more accessible for replacement would have been nice.
Tired of fooling around with tube amps? Had enough? Finally figured it out that tube amps give you a great sound, but just ONE sound. Then get yourself a Voodu Valve and spend some time tweeking all its parameters. Sound for sound, tone for tone, you'll save lots of money and time. I've gone the tube amp route, even built my own. To get all the sounds from tube amps that you can get from the Voodu Valve you'd have to have 50 or more of 'em.