I purchased a Behringer VT911 and took it apart AND ..... I have to tell all here that this is
not even remotely similar to the B K Butler Tube Driver.
First it runs off 9v dc ,
NOT 12vAC (which is converted to +12vDC and-12vDC in the B K Butler)
It has a crappy single knob tone control in place of B K Butlers HI and LO controls.
It has a Coolaudio brand chip - unsure what it is - looks like a quad opamp SMD device in place of the B K Butler TL072 or 4558 dual opamp.
AND ...................it sounds like a badly biased germanium Rangemaster - you know, that shitty gated distortion effect in comparison to the smoooooth sounding B K Butler Tube Driver.
No wonder Behringer discontinued it - does any one have a schematic for it????
My local Behringer tech friend does not have it - I am contemplating doing some mods to make it a useable unit - then again, maybe I will just put it on the local Trade Me site (NZ Ebay) and see if I can get some money back
Anyone with a schematic - factory or otherwise email me
baja002@clear.net.nz - I will not say where I got it okay
Do yourselves a favour DO NOT BUY one of these - build the B K Butler Tube Driver in the DIY Projects section instead
cheers
bajaman