I got a response finally! This is for the new Ashdown LB30 2N if anybody wanted some info.
"Hi William
Dealing with the EQ first
The EQ consists of of a 4 way filter that splits the signal into 4 bands each of these is fed to 4 individual volume controls the outputs are then remixed to give the complete signal
As regards the subtract part of the debate, lets say you take a subtract eq and boost the signal Before sending it into the eq, with linear pots set at 50% the level can be the same as it was beore the eq ,you can now get a boost or cut out of the eq
It is a generally held opinion that the passive eq circuits (ie those without and active element and the required feedback) sound more musical I don’t have an opinion on this
The SVT has an artifical diode distotion circuit, similar to the type found in generic pedals ( mxr tube screamer etc ) the LBTN does not , this is not a problem since you will find all the grind and distortions available within the Two Notes programs , so you do not need to run the amp hard at all which is why it is desgned to be clean as far as possible"