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Fourth preamp tube

Posted: Tue Nov 17, 2009 10:20 pm
by LP Freak
Does anyone have info on adding an additional gain stage by adding a fourth preamp tube? I'm looking for diagrams not schematics.

Re: Fourth preamp tube

Posted: Sun Nov 22, 2009 6:14 pm
by itsonlyadam
http://home.comcast.net/~jbjdav26/2203% ... 20Rev1.jpg" onclick="window.open(this.href);return false;

I guess that would help. I took it from Steve's (SDM) site. Found it under the Misc. Mods section.

Re: Fourth preamp tube

Posted: Sun Nov 22, 2009 10:19 pm
by LP Freak
Has anyone tried this? I was wondering how it sounded.

I also see that Rockstah was doing the rocca mod. I was wondering if that would be better. Does anyone have a diagram of the rocca mod? I'm not looking for alot more gain, but a touch more. Just enough to put it over the edge. I still want the amp to clean up whan I back off the guitar's volume.

Re: Fourth preamp tube

Posted: Mon Nov 23, 2009 5:28 pm
by jerrydyer
they are almost identical. I would like to hear this one. I think there is a clippie somewhere else on this forum.

Re: Fourth preamp tube

Posted: Mon Nov 23, 2009 6:38 pm
by axeman
I built her once, but then turned it into a stock 2203.

Sorry no clip.

Re: Fourth preamp tube

Posted: Mon Nov 23, 2009 6:46 pm
by Guitar Adjuster
I built this one a year or two ago, lots of gain about 40% more then a "stock" 2203.

Image

Re: Fourth preamp tube

Posted: Mon Nov 23, 2009 6:56 pm
by axeman
That amp is beautiful Guitar Adjuster, good job. Any audio clips?

Re: Fourth preamp tube

Posted: Mon Nov 23, 2009 10:19 pm
by Guitar Adjuster
axeman wrote:That amp is beautiful Guitar Adjuster, good job. Any audio clips?
No clips, I built it for a friend a few years ago. It was a beast for sure. I am in the process of building another just like it but with Sozo Caps and those Sozo Royal Blue 100 can caps. Drilling the board right now, chassis is all wired and ready to go.......just got to find the time to finish it.

Allen

Re: Fourth preamp tube

Posted: Tue Nov 24, 2009 12:30 am
by Coot Boy
Im thinking of doing this to my 2203 clone. If anyone has something to say about it, let's hear it please.
axeman wrote:I built her once, but then turned it into a stock 2203.
Sorry no clip.
axeman, what can you say about it, why did you put it back to 2203?

Re: Fourth preamp tube

Posted: Tue Nov 24, 2009 1:57 am
by axeman
First of all, it was all gain lacked tone, but fixable. Steve Miller helped me with it, he recommended tweaking some caps and experimenting to find that spot. Give it a shot, I have a new board for that amp if you need one.

Re: Fourth preamp tube

Posted: Tue Nov 24, 2009 9:57 am
by LP Freak
That's exactly what I'm afraid of. I love the tone of the amp the way it is. I'm just looking for little more gain.

Re: Fourth preamp tube

Posted: Tue Nov 24, 2009 10:33 am
by Guitar Adjuster
LP Freak wrote:That's exactly what I'm afraid of. I love the tone of the amp the way it is. I'm just looking for little more gain.
If it's a stock 2203 there is plenty you can do to get a little extra gain without adding a 4th tube......

Re: Fourth preamp tube

Posted: Tue Nov 24, 2009 4:59 pm
by LP Freak
Any suggestions? I was looking for the rocca mod but couldn't find any info on how to do it.

Re: Fourth preamp tube

Posted: Tue Nov 24, 2009 5:11 pm
by Coot Boy
I've tried the rocco thing, I didn't like it, not real sure why now, it's been a while.
This link was posted on another thread and this is what inspired me to think about the extra tube as i'm pretty sure you won't get this tone without it, or am I wrong.
http://www.youtube.com/watch?v=3ZF46owj ... re=related

Re: Fourth preamp tube

Posted: Tue Dec 01, 2009 11:02 pm
by ezs
LP Freak wrote:Has anyone tried this? I was wondering how it sounded.

I also see that Rockstah was doing the rocca mod. I was wondering if that would be better. Does anyone have a diagram of the rocca mod? I'm not looking for alot more gain, but a touch more. Just enough to put it over the edge. I still want the amp to clean up whan I back off the guitar's volume.
It sounds like a bad attemt to get high gain. Its a great layout however, it will get you started to dialing in your own values. As is, way too much bass, mush etc. Otherwise a great 4 stage CF platform.