I have recently purchased a SVT-CL and was wondering if it was ok to use the unpadded (0) input using a Musicman HH 4 string, if so how hard can you push the gain, so far I have had a quick try in the 0 input but mainly been using the-15 input, secondly being new to valve amps, I have been having the gain set at 8 and I don't seem to get a dirty signal, again should I be using the 0 input? any advice is apprieciated.