Welcome to Solid State Guitar Amp Forum | DIY Guitar Amplifiers. Please login or sign up.

March 29, 2024, 07:20:19 AM

Login with username, password and session length

Recent Posts

 

Trace Elliot Supertramp

Started by Dutch, July 01, 2008, 04:03:27 AM

Previous topic - Next topic

Dutch

Hi there,

I am new to this forum, but I have to say I am glad to find an SS forum, so I don't have to worry about narrowminded people, that keep telling you how stupid you are for playing a SS- Amp..You NEED TUBES!!! Enough wining for now..

I just bought a superb looking and sounding Trace Elliot Supertramp. Built approx. 1995, 80 watts, 2 channels, 2 drive modes, boost, presence, mastervolume, spring reverb, Celestion G12T-60..


My question..would it be possible to make the drive mode footswitchable? Now there is just a tiny switch and I would like to have the option to switch it by foot..Does anyone here tried something similar like this? Something I need to consider?

Cheers,

Dutch

teemuk

Quite a lot is possible but I have a feeling that a modification like that would be quite difficult to implement and therefore it's maybe not worth it. If you take a look at the schematic (see my recent post at the "schematics" section if you don't have one yet), you see that the "mode" switch SW1 is a SPDT switch that selects between two signal sources, one of them passing through few more gain stages. Since the switch seems to be at a high gain signal path you likely can't just take it to a remote location (e.g. foot pedal) without introducing noises, oscillation or some kind of misbehaviour. However, you could replace that switch by a relay, JFET, LDR - or any suitable switching element - and then build a switching logic circuit that is controlled by a separate footswitch. (Sort of like what they did with the other switches.) Naturally you would have to design this circuit, likely build a circuit board for it, figure out the way to mount it, drill a hole for a footswitch jack etc. Technically – and in theory, the modification, by itself, is quite simple if you know what to do but it will require quite a lot of work. In practice there also may be many reasons that make implementing the mod extremely difficult. For example, there is a very good chance that the switch is mounted to a PC board with a very small clearance to chassis and you will not really have room to install the mod – at least not neatly. But yes: circuit wise it certainly can be done.

Dutch

Dear Teemuk,

Thanks a lot for all this information. I thought this mod would be relativley easy...Good thing to check this forum first, because I tend to think I have some knowledge on electronics, but there is really still a lot to learn..Thanks, I will think this over and open the Supertramp up, and check what's inside..

Keep up the good work here..

Cheers,

Dutch

Jack1962

It looks fairly simple to me from the scematic I have , I don't see a SPDT on my diagram it shows a SPST, looks real simple take out the switch run some sheilded cable to a footswitch, looks simple to me. Which diagram are you going by Teemuk I'm looking at the Supertramp& Twin Tramp diagram ?

teemuk

I use the same diagram and I see a SPDT switch. What comes to shielded wire run ...well, it could work - and if it does, good – but I have my doubts: With all the high gain and the high load impedances involved I think a few meter wire run to a foot pedal is not such a good idea - even if shielded, which would be mandatory anyway. As I mentioned, that configuration could easily add more unwanted noises - or at worst burst into oscillation. If I would try to implement something like that I would at least buffer that wire run.

Jack1962

Quote from: teemuk on July 03, 2008, 03:07:25 PM
I use the same diagram and I see a SPDT switch. What comes to shielded wire run …well, it could work - and if it does, good – but I have my doubts: With all the high gain and the high load impedances involved I think a few meter wire run to a foot pedal is not such a good idea - even if shielded, which would be mandatory anyway. As I mentioned, that configuration could easily add more unwanted noises - or at worst burst into oscillation. If I would try to implement something like that I would at least buffer that wire run.

I yes I see the what your saying , loads of gain, after looking at it further, I don't know , it is possible , you would have to build a buffered relayu circuit ( to prevent RF oscillation and pop when switching) as Teemuk stated, hoever all this can be done by the a DIY'er if the person really wanted to, myself I would just plug my TS9DX in more than enough gain from it or most any good OD or Distortion pedal. With the same footprint(stuff on the floor).

                                        Rock On