Bk butler real tube mod#
Bk butler real tube driver#

It's true that it has real tubes in t here, but most of the signal path is NOT tube, and the tubes are run at very starved voltages. I like BK Butler's designs, but I was always a bit bothered by the deceptive name 'real tube'. Really not a bad sounding preamp if you find one cheap, but you won't be happy if you're chasing a good Jerry tone. They don't have the pure, immediate, tubey sound of an actual Jerry/Fender type tube preamp. They're ok, but they have a lot of staging (lots of components the signal passes thru) and a strong solid state tone character. The Butler 'tube' preamp is actually, for the most part, a transistor (op-amp) preamp with a couple of tube stages to help with the tone.

Bk butler real tube driver#

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 backДЄnyone with a schematic - factory or otherwise email me - I will not say where I got it okayДo yourselves a favour DO NOT BUY one of these - build the B K Butler Tube Driver instead No wonder Behringer discontinued it - does any one have a schematic for it? 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. 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.ДЄND. It has a crappy single knob tone control in place of B K Butlers HI and LO controls. I have to tell all here that this is not even remotely similar to the B K Butler Tube Driver.ДЇirst it runs off 9v dc, NOT 12vAC (which is converted to +12vDC and-12vDC in the B K Butler) I purchased a Behringer VT911 (reputedly similar to the B K Butler Tube Driver), took it apart AND.

Bk butler real tube mod#

Tube Driver Bottom PCB layer parts placement and bias mod How does it sound? I did not care for it - but then I have been spoilt by a real tube overdrive ( 250v dc plate load feed as opposed to this 12v beastie) I think you may be able to improve it's sound by using a higher spec op amp such as the excellent Burr Brown OPA2134 and by using better quality metalised polyester or polystyrene film capacitors - who knows?ДЄnyway - big drum roll. Good luck if you want to build it - it uses a double sided circuit board. It uses a TL072 op amp and 47k plate load resistors and many other subtle changed components - more later. I have not redrawn the schematic yet - it should be up in the next few days - it is not the same as ANY of the many schems floating around on the net by the way. The additional bias control pot is mounted above the input socket on the rear panel - I preferred it without the additional bias resistance and capacitance - but others may find this B K Butler mod useful. There is no mojo components in here - just cheap mylar greencaps and standard metal film resistors - so It won't sound very good - tell David Gilmour and see if he cares - he has two of these exact same pedals in his Pete Cornish pedalboard The earth pin on the input socket is connected by a parallel connected 100 ohm resistor and a cheap 100n mylar capacitor to the chassis near the front of the case. The input and output sockets are isolated from the chassis by plastic insulating spacers. You will need a suitable 12vAC power pack for this pedal - the original has a small toroidal mains transformer fitted internally near the front of the case. This was traced from a recent B K Butler pedal and has the bias pot modification which alters the voltage on the cathodes of the 12AX7 tube.