1987 + 2204 2 in 1 Build Questions

[PeterJ_22]

Hi guys I want to build a 50w plexi / jcm800 in 1 amp.

However I want it to look dead stock plexi from the front (aka no extra knobs etc).

Obviously without adding any extra tubes I will only have the plexi bright channel (2k7 / .68) and the jcm800 cold cathode (10k).
So I was thinking I use the bright channel volume 1 for the bright plexi volume and the volume 2 (which would of been normal channel volume on a 1987) as the gain control for jcm800 mode. Leaving the bright volume as a kind of master in.

Any ideas of adding a switch to engage the cascaded gain stage.

I figure this is sort of similar to a 1 wire RR mod with the normal channel cathode changed to jm800 values?

However I can't seem to find a 1M Audio dpdt anywhere so was thinking of just using a toggle switch?
Another option could be having one of the 4 jacks wired up for jcm800 mode and the other for plexi?

I don't need to have the option of remotely switching modes etc so no need for relays / footswitches etc.

I just want the versatility of having both circuits in one head.

Any thoughts would be great.

Cheers - Peter

[woold]

I would be tempted to use a relay switched using a 1M pot with a pull switch like this.

http://www.ebay.co.uk/itm/VOLUME-CONTRO ... 231f455a8f" onclick="window.open(this.href);return false;

[Thiez]

Look at this site, here's a lot of info on a 2 in 1 mod like you want.

http://home.comcast.net/~mamp17/Misc%20 ... 0Info.html" onclick="window.open(this.href);return false;


This layout
http://home.comcast.net/~jbjdav26/1959% ... 20grnd.jpg" onclick="window.open(this.href);return false;

[neikeel]

This is the pot you need:http://www.tubeampdoctor.com/en/shop_Po ... ervolum_29

That is the one I used on my layout on SDMs site.

If you want it to look totally stock you will have to share one half of the dual pot (vol 1) as MV and the other as master in that mode, the other will have to be gain pot and vol 2 on each half, if you want to be able to switch the mv off you will need two of these pots, one to switch modes, the other for the mv.