Modding the "BEAST"...the Framus Cobra

Joined
Jan 21, 2014
Messages
2
Reaction score
0
Age
55
:D

I'm starting a new thread to maybe get some people in on the various mods that have been done over the years on Cobras. I'm in the middle of getting mine (a V5 I think, since it has the bias points in back) cleaned up, re-worked and and made into the killer amp I think it can be. When I bought mine used a couple of months ago, it was noisy as HELL, and very brittle.
So, I asked around and found a guy called "The Tone Doctor"[/U][/B]8:. I asked a bunch of questions and he assured me that he can do whatever we want. So far, he's proven to be VERY knowledgeable and easy to work with. Besides.....he's a great player and tone junkie in his own right! So, now we're going through the entire amp replacing all of the cheesy 1/8th watt resistors that China decided to skimp by using that could very well be the start of the problem. We're now using 1 watt resistors in their place. After that, he plans to add a choke :D and replace some or all of the little programmable chips that govern the gain structure. What he's found is, that these little buggers have to do with how the gain stage acts. I'm not exactly sure what they do specifically, but he is. But, 1 of the big problems of this amp in particular is, that when you roll down the volume knob of the guitar or the gain knob on the amp, it seems there's 2 sounds going on at the same time. It's as if there's a clean sound getting louder as the dirty sound fizzles into nasty oblivion. It's not very musical sounding. There is a series of chips on the diagram from Framus that are labeled "OK1-12". These seem to be the ones he's referring to on Page 2 of the following schematic. I just included the 1st 5 pages of the schematic, because that's what's pertinent to this post. Framus V5 page1.jpg Framus V5 page2.jpg Framus V5 page3.jpg Framus V5 page4.jpg Framus V5 page5.jpg
 
Joined
Nov 14, 2015
Messages
3
Reaction score
0
Hello sorry but I don't see how the midi control chips can affect tone or low gain in any way.

I'd go as far as saying he is knowledgeable but he throws words and stuff around just to guide you to do business with him and be happy. I am not saying he is going to harm the amp.

Also using bigger rated resistors is more safe but can change tone and even raise noise. And the cobra is a bit noisy on its own. If the amp doesn't fail on you constantly with those resistors as the source why bother?

As far as re-voicing the amp it can be done without hacking any of the stuff he is mentioning. You can mod it to dragon spec for example on any of the channels easily. Page 2 is not a schematic, just the pcb drawing of the preamp I think?

Personally I wouldn't exactly believe him to be honest.
 
Joined
Nov 14, 2015
Messages
3
Reaction score
0
The only think I can think of your tech meaning is those control chips blending the clean and crunch/lead path simultaneously. Ask him if this is the case.
 

Augie

The Desert Bass-ape
Joined
Mar 11, 2010
Messages
2,225
Reaction score
203
me play bass.
loud bass good.
amp make bass loud.
amp good.

That is the sum total of what I know about amps.:p
 
Top Bottom