JCM900 conversion...?

[Iron Broadsword]

I've heard people talk about this and have been wondering about it... I have a JCM900 4100 (dual reverb) that I love, but since I don't have the money to buy a second amp I was thinking of tearing out the guts and converting it to a JCM800. I know I can do the work, but this is just me looking into whether it's even possible. My main issue is would I be able to use the same transformers? The idea is that I'd keep the 900 boards intact when I strip them out, so that I can easily convert it back.

Thoughts? Info? I've been building circuit boards for a long time and know my way around an amp somewhat.. I can do this on the cheap if it's possible, lol.

[cbass]

Why would you gut an amp you love?

Do you beat your wife?

[Iron Broadsword]

Er, no. What I really want is to be able to get both tones and ideally I'd have both amps. I'd settle for the ability to modify it back and forth to suit my current need.. but what I'd really love is to be able to swap out the 900's preamp with a JCM800's at the flick of a switch.

Hmm......... I guess I could build an 800 preamp and ride it into the 900's fx loop return.. Now that's interesting. Sorry, thinking as I type here.. Gonna look into that. I think I'd have to buy a transformer for this though, right? Trying to avoid that.

[Iron Broadsword]

http://www.ax84.com/bbs/dm.php?thread=329775
http://i172.photobucket.com/albums/w5/k ... 9/vtr2.jpg
http://i172.photobucket.com/albums/w5/k ... e002-3.jpg

That right there is pretty much what I'm after, I think. Will have to research this!!!

[10thTx]

I gutted a JCM900 for a friend of mine and converted it into a Plexi 50w with reverb. My friend wanted the conversion as inexpensive as possible and didn't even want to replace the pots.

Here is a picture of the conversion. I certainly used the same trannies. I think it was around $130 to convert it without the reverb tank, IIRC?

http://s28.beta.photobucket.com/user/tu ... 8848032664

With respect, 10thtx

[Iron Broadsword]

Nice! And thanks for that.

I'm not interested in a plexi (got a class5 and that's close enough at the volume I need it for) but this gives me hope. I'm gonna have to take some time and really do my homework of course

[badtweed]

Here's a one off I did for a friend who wanted something different.


http://ampgarage.com/forum/viewtopic.ph ... highlight=