I've been itching to modify my amp...

[wampcat1]

Has anyone else modified theirs? I imagine it's the same basic idea as pedal mods, but just includes dangerous voltage? Anything I should watch out for?

[petemoore]

What areyou starting with?

[Melanhead]

Got into it about 7 years ago and played around with amp modding for a few years then had children ( well not me, my wife! ) ... I forgot most of it but it's essentially understanding the signal path and how the preamp section works...

This is the book I read as it walks you through the stages of a tube amp without getting overly complicated ... Sorta like a "Tube amps for dummies" book would be

http://www.torresengineering.com/inbydantor.html

Good luck .. I'm sure you can do it though ... I worked mostly on 70's Fenders and JCM Marshalls as they are easy to mod and work in ...

[MartyMart]

...... ahem, yup there's a BIG difference between putting your tongue
across a 9v battery........ and 300v - 600v inside a tube amp  !!!

but so long as you DON'T do that, yes you can adjust the input stage and
pre-amp stages in a similar way, ie gain/tone shaping etc ....
What amp is it ?
schematic ?

Marty.  :wink:

[Melanhead]

...... ahem, yup there's a BIG difference between putting your tongue
across a 9v battery........ and 300v - 600v inside a tube amp  !!!

but so long as you DON'T do that, yes you can adjust the input stage and
pre-amp stages in a similar way, ie gain/tone shaping etc ....
What amp is it ?
schematic ?

Marty.  :wink:

Yup ... that's probably why I don't do it much anymore .. I'm more cautious now and the high voltages freak me out !!!

[wampcat1]

Several amps -- the peavey classic 50, and a new crate tube amp, the palomino, which is similar to a vintage club I believe.

Thanks,
Brian

[R.G.]

Do yourself a favor - go buy "The Ultimate Tone" volume 1 by Kevin O'Connor at the Power Press Publishing web site. It's about $50, but it's some of the most cost effective education you'll ever get.

[MartyMart]

Several amps -- the peavey classic 50, and a new crate tube amp, the palomino, which is similar to a vintage club I believe.

Thanks,
Brian

Brian, if you do a search, there was a quite recent post about modding a
classic 50/30 - can't remember, but there was a link to a site with a kind
of "step by step" guide to doing this ..
Looked interesting and very informative !
I love my '30 and dont want to mess with it !!
Good luck,

Marty.

[wampcat1]

Several amps -- the peavey classic 50, and a new crate tube amp, the palomino, which is similar to a vintage club I believe.

Thanks,
Brian

Brian, if you do a search, there was a quite recent post about modding a
classic 50/30 - can't remember, but there was a link to a site with a kind
of "step by step" guide to doing this ..
Looked interesting and very informative !
I love my '30 and dont want to mess with it !!
Good luck,

Marty.

I'll see if I can find it - thanks!!

I like my classic 50 too -- I guess I'm just a 'tinkerer' by nature and just want to goof around with it  :lol:
Thanks,
Brian

[Paul Marossy]

I modded my Hot Rod DeVille more to my liking. I was kind of on my own on that one. When I was done, the differences were subtle. Mostly I was trying to warm the amp up some.

[cd]

Do yourself a favor - go buy "The Ultimate Tone" volume 1 by Kevin O'Connor at the Power Press Publishing web site. It's about $50, but it's some of the most cost effective education you'll ever get.

And Vol.3 if you're looking for more hands on building type of stuff.  Also when reading Vol.1 keep in mind it was written in 1995, some of the info (epecially about Chinese and Russian tubes) is out of date.

Oh yeah, do yourself a favor, ask questions on AMPAGE (www.ampage.org) rather than a stompbox forum!

[Paul Marossy]

Yeah, the guys that hang out at ampage and ax84 are all helpful and pretty sharp.  :wink:

[wampcat1]

Do yourself a favor - go buy "The Ultimate Tone" volume 1 by Kevin O'Connor at the Power Press Publishing web site. It's about $50, but it's some of the most cost effective education you'll ever get.

And Vol.3 if you're looking for more hands on building type of stuff.  Also when reading Vol.1 keep in mind it was written in 1995, some of the info (epecially about Chinese and Russian tubes) is out of date.

Oh yeah, do yourself a favor, ask questions on AMPAGE (www.ampage.org) rather than a stompbox forum!

I'll never understand why you are always sarcastic.

My meaning is this. working one pedals = working on amps + more capabilities/danger?

:roll:

[wampcat1]

Do yourself a favor - go buy "The Ultimate Tone" volume 1 by Kevin O'Connor at the Power Press Publishing web site. It's about $50, but it's some of the most cost effective education you'll ever get.

Thanks RG -- I'll do it! I had checked out Torres book, but I hear so many negative reviews about his mods that it has kind of made me leery... of course, those are just gossip reviews, so they could be way off base!  :lol:

Also, RG - are you going to the visual sound grand opening in July?

Take care,
Brian

[AL]

I can't seem to keep my nose out of amps lately. I haven't modded any but I have breathed some life back into a few older amps ('72 Quad Reverb, '68? Ampeg SB-12, currently working on a '70 Traynor YSR-1 and a '66 Ampeg Gemini 1). I'm amazed what some basic maintenance will do (cap job, new tubes, proper bias). It makes older amps look like a pretty sweet deal compared to some of the prices on new ones.

I have the Groove Tubes book wich has some good info in it and a load of schematics. I haven't seen the Kevin O'Connor book but I'll have to check it out too.

Good luck, have fun, and be careful.

AL

[petemoore]

My  left arm got bit by a big cap in an SLP, these things always made me nervous.
 I went in and re-modified my 50W MkII Ch1 input, it was adjustable between .9 and 9. when turning it from 830:12 to 830:14...way super touchy, coudln't be used at anything except lowest volumes...now it works flawlessly, and the high end 'spike in the forehead' BITE, is now a nice Growl. I needed the mod like real bad, way too much treble to begin with, and the volume knobs teensy glitch in the wrong spot is now just gone.
 Other than having a clear objective and course of action, I find these tube amps generally are set up to work quite well enough to leave well enough alone [except in the case of the MkII...]. Of course the more 'know how' types here and at ampage I'm sure could help find the mods that might 'improve' them.

[Ripper]

I've been working on tube amps for years, and just recently (within the last year) got into doing pedal mods/building (I'm an electronics technologist).  I've got to thank wampcat for his great pedal mods, I've been very very pleased with them.

Tube amps are alot of fun to mod.  I modded an old Peavey Triumph 60 head I had and it turned out really well (friend of mine has it now), as well as piles of fenders, marshalls, ampegs, garnets and the like.  One thing you'll find once you get into it is how "similar" some amps are to others, which makes it easier.

the one I'm working on right now is an old Fender Super Twin Reverb that had been put onto the trash heap.  It's just a chassis, no cab no speakers, but the transformers are good.  It is missing a ton of parts and needs some real TLC.  I'm going to see what I can do to mod it out as I don't really need a super clean 180w amp (6 x 6l6's).  It's also fun to take old tube audio amps (either mono or stereo) and mod them for guitar.  You can get some great sounding "boutique" amps out of it.  Just make sure though you aren't hacking up something that has collectors value.

Good luck wampcat and have fun!

[wampcat1]

I've been working on tube amps for years, and just recently (within the last year) got into doing pedal mods/building (I'm an electronics technologist).  I've got to thank wampcat for his great pedal mods, I've been very very pleased with them.

Tube amps are alot of fun to mod.  I modded an old Peavey Triumph 60 head I had and it turned out really well (friend of mine has it now), as well as piles of fenders, marshalls, ampegs, garnets and the like.  One thing you'll find once you get into it is how "similar" some amps are to others, which makes it easier.

the one I'm working on right now is an old Fender Super Twin Reverb that had been put onto the trash heap.  It's just a chassis, no cab no speakers, but the transformers are good.  It is missing a ton of parts and needs some real TLC.  I'm going to see what I can do to mod it out as I don't really need a super clean 180w amp (6 x 6l6's).  It's also fun to take old tube audio amps (either mono or stereo) and mod them for guitar.  You can get some great sounding "boutique" amps out of it.  Just make sure though you aren't hacking up something that has collectors value.

Good luck wampcat and have fun!

Thank you!

[aron]

I've been working on and off on my amps since R.G. got me started with my 65 blond bassman. (Thanks R.G.)

Since then I've modified several amps and my Traynor is my favorite. My hacked bassman (another one) is currently in "mod hell".

I have bought many books since then, TUT v1-3 and much more.

WARNING it's addictive like pedals, but after all is said and done, I still love pedals a lot more.

[ErikMiller]

The best description of what each stage of a tube amp does is in Dave Funk's Tube Amp Workbook. It's oriented toward Fenders, but the information applies to most tube amps.

I also recently obtained Mike Thompson's Great Tube Amp and Guitar Mods, which is a compilation, and it's got some fun stuff to try.

As an amp repairman myself, I occasionally hear from someone who's hot to get their amp modded. Invariably, they tell me "I really like the way it sounds; do you have any cool mods for it?"

I suggest to them as gently as possible that if they "really like the way it sounds," the best way to play around with the tone is to try different brands of tubes rather than changing the character of the amp with a mod.

Tubes make a BIG difference. Especially in the preamp section. 12AX7EH's, JJ ECC83's, JJ ECC803's, vintage tubes, they sound WAY different, both when clean and when driven to clipping.

Mostly, the people who designed the major brands of amps knew pretty well what they were doing. When CBS took over Fender, yes, they buggered up some of circuits, but it's pretty minor to change them back to Leo style.

Every amp that I work on has its own character, and usually (not always) that character is good, and it just takes proper adjustment, cleaning, and new tubes to bring it out.

Having said that, I just had a Fender "Twin Reverb II" head in here, from the Paul Rivera era. Both the clean and the crunch channel sounded like hell, even after retubing. Lifeless. What a waste of point-to-point construction.

The guy told me he got it for free because his friend never liked the way it sounded, and I understand the friend's pain.

If someone gave me one of these and I couldn't sell it, I'd strip it and rebuild it as a Showman.