Some classic information

This is from Ken Fisher. I met him when he worked at Ampeg.
Pages 33,34,and 45 are especially good info for how gain stages work.
Easy to apply to module mods.
http://www.blueguitar.org/new/schem/trainwreck/the_trainwreck_pages.pdf

I'm not a DIY guy, but certainly some good reading. Thanks for the post.

http://www.freewebs.com/valvewizard1/Common_Gain_Stage.pdf

Here is some very basic info on gain stages (preamps) and how they work. I have modded my own modules since shortly after becoming a MTS junkie and this is the first few chapters of the book I used to understand the theory of preamps. I realize there has been some discusion on the DIY page about not copying peoples work. We all learn by copying other peoples work. Thats how I learned! Most of the modules that are modded are copies of other peoples work. The entire MTS line is based on copies of other peoples designs and hard work. If this forum is not open to sharing what we know or have learned why have it? I respect the fact that modders have put hours of research into learning how to modify preamps to achieve a desired sound or replicate other amplifiers. I have no intention of taking work away from anyone here or have any desire to be a "modder". I do feel like this topic is a bit taboo on this forum. Either way, if you want to learn there are plenty of resources on the web that can take you far beyond the basic gain mods or cap mods that are being done. I have done dozens of mods on my own modules and I did them from info I obtained from reading books or the web. I hope the wannabe modders out there take the time to study how preamps work prior to modding there modules. Once you understand how things work it's much easier to make modifications and know what to expect from the result.

Knowledge is certainly the best tool when it comes to tweaking. It's always best to understand something and how it works before jumping in. It avoids a lot of problems and harm down the road for sure.

A friend of mine has a saying: "Think 10 times and act 1 time." So do some studying so that you have a basic understanding of the subject at hand and create a game plan. Don't rush into modding your equipment or you might regret it.

kc2eeb & roszatycki: thanks for the links. this is the kind of stuff i have been wanting to learn about and i can use all the resources i can.

I want to add this link also (contains similar information):

http://www.aikenamps.com/CommonCathode.htm

JKD said:

I want to add this link also (contains similar information):

http://www.aikenamps.com/CommonCathode.htm

Click to expand...

Really good info!!
Eedude sent me a link to this a while ago and it is full of good stuff. My advice is take it slow and digest each cluster of data one by one.

Here is a site I've discovered with is much more generic, so probably not as helpful on guitar power/preamp theory. However, I do like the history section at the beginning. I finally know why the plate voltage is usually called B+.

http://mysite.du.edu/~etuttle/electron/elect27.htm

P.S. I'd love to put one of the electron ray tubes on my amp, just for show. Wire it up to show when the power amp is driven into distortion would be cool.

Here is an article i just found that offered some good insight into the analysis of the common cathode configuration. i got excited when i saw the partial derivatives...my brain has been more active in the past hour than it has all summer hope someone else finds this useful as well.

http://bear.cwru.edu/eecs_cad/tut_spice3_tube.html