Improve Your Guitar Amp Sound with These Pro Tips | Amp Polishing Guide

[guitarguy66]

hey guys i plan on fixing up this old behringer vintager that honestly sounds like a piece of dirt. the amp is a solid state/ tube hybrid with 1 12ax7 tube in the pre amp. i plan on taking it and just using the fx loop out to only get the pre amp section and hook that up to my computer. from there i will use a cab simulator. this is basically just something I am doing for fun and to have some fun late night recording.

alright so i want to find ways to make the pre amp sound better obviously. i would like to add an extra 12ax7 to the circuit, but my question is would i have to change anything else out on the circuit to make it work. would this even be a good idea? is there anything else i can do that will help my sound?

i did notice it has a digital effects unit built in. it is never used (the effects sound like hammered crap) but I am wondering if even with it being off is it sucking tone from the amp? would i be able to just undo the stupid thing and it be ok? is it really even harming my sound?

sorry about these noob questions. I am a fresman mechanical engineering major and i havnt learned much at all to be honest since I am just a freshman. i know what the electronic componets are but i don't have very in depth knowledge of how the whole circuit of an amp works. I am finding it difficult to find good information on amps and whatnot. i realize this task would be a lot easier on yall if there was a schematic but i can't find one anywhere. i plan on taking pictures and posting them hopefully tomorrow of the circuit board.

even if everything i said is stupid please explain to me why. I am not opposed to learning anything new so school me if you have to.

 

[Fish4Fun]

guitarguy66,

Welcome to PF!

It is very difficult to "add components" to an existing design and improve the functionality. As you are a mechanical engineering student I will give you a mechanical analogy: " I have a four cylinder Toyota, and it accelerates like nothing, I want to add a fifth cylinder to improve the 0 to 60 performance, what type of piston should I get and where can I find some good information on how to install it."

On the surface both my analogy and your OP seem reasonable enough, and neither are impossible, but in reality both are quite impractical and would require a massive undertaking to achieve. You would be far better off simply purchasing an Amp that is more to your liking as I might to simply purchase a car with enough acceleration to satisfy me.

Fish

 

[guitarguy66]

I see what you are saying. that makes sense. I figured it would be difficult, but i wasnt rreally sure why lol. I am just a college freshman, so as you can imagine i havnt learned that much so far. I do have an amp i use to gig and practice with, this amp is just a project i was going to use to have some fun with lol. That piece of dirt needs to useful for something other than taking up space.

 

[Bob S]

There are several schematics for 12AX7 preamps.

http://www.google.com/images?hl=en&...it&cp=21&rlz=1C1RNNN_enUS345&bav=on.2,or.&bs=

There are basically three different designs of 12AX7 dual triode preamps:

1) Two hi-gain stages, with a plate output (will need a cathode follower for driving a cable)
2) Fully differential triode pair, again with a plate output.
3) Single triode hi-gain stage, with the second triode used as a cathode follower.

We usually preferred the Telefunken brand of 12AX7's because they had the lowest noise. A problem with vacuum tube amplifiers is that they require ac (capacitor) coupling between stages because of the large voltage difference between plates and grids. Sometimes for dc amplifiers (like in vacuum tube oscilloscope vertical amplifiers) we would use a NE-2 neon bulb for coupling, because the voltage drop is independent of current..

Bob S

 

[turbo]

@ OP: You should consider building a clone of a Fender Champ. The circuit is very simple, and the sound is killer when matched with a decent speaker. Look to Weber for a good vintage-clone speaker, and I'd suggest going to a 12" speaker with alnico magnet. Little amps are sweet.