Need inspiration.... Super Champ XD rebuild....

[Deric]

Help me out.....

I have a dead Fender Super Champ XD combo. DSP board is dead but everything else works. Unfortunately, the pre-amp is mostly DSP based (not just the FX) so I can't just bypass the DSP....

No big loss...was just going to throw it away...but....

The PT puts about 375vdc on the 6v6 plates. Has a 6.3vac heater winding....I think I could sneak in one more 12ax7 without taxing the PT too much... There is also a 9vac winding and a 34vac winding (17-0-17).

Soooo..... I'm thinking a 2 x 12ax7, 2 x 6v6 single channel clean amp. Use the 9v secondary for relays and the 34v secondary to power an overdrive/distortion circuit ala Tubescreamer or similar...could possible even power a SS spring reverb circuit....

Don't really want to spend much money on this.....just bored and looking to make something out of this POS.

Have lots of beer and spare parts....

Ideas? Suggestions?

[Blackburn]

First, you want to mount the beer and then proceed to eat the parts. Maybe reverse how you go about that, YMMV.

Sounds like fun. I love broken down newish Fender stuff. Trannies and cab are there, as well as a chassis. Lots of options. How about a SE 6V6 with trem like a Vibrochamp? An extra couple stages to go nuts? Much to consider.

[xtian]

I remember a LONG thread on modding the XD, wherein guy added a 12ax7...foggy on whether it worked!

Anyway, mine is gone, but I had modded it with a simple 1/4" input jack straight into the PI, so I could avoid the digital preamp and go straight to the tubes. Had to boost my signal with a boost pedal, so the "all tube" goal wasn't met, but it was a whole lot quieter (less hiss from the XD's preamp).

My point is, simple-est solution is to build a quick FET or other boost (with EQ or not) into the input jack, run that straight out to the PI, and you've got a working, clean-to-mean, nearly-all-tube amp!

[Deric]

My point is, simple-est solution is to build a quick FET or other boost (with EQ or not) into the input jack, run that straight out to the PI, and you've got a working, clean-to-mean, nearly-all-tube amp!

Agreed! However..... Already gutted it. Just have the bare chassis, transformers, cab and speaker.

Did find the thread about the guy adding a tube and building a 5e3-ish thing. No clips but looks like it worked OK.

I was thinking 5e3-ish with a relay switchable S.S. overdrive (ala Tubescreamer, Zen or maybe OCD) in front. Maybe add a loop between the two or even an S.S. driven tube verb.....

Been staring at the chassis sitting on my desk trying to get inspired.

So far......beer wins.

[Cliff Schecht]

Build a Rivera-era Super Champ. They're killer amps!!

[Deric]

Cliff,

Thanks for the suggestion! Looking at the schematic I can't get my brain around a couple of things:

How does the "Lead" switching work? Google took me to this thread but the link is dead....

https://tubeamparchive.com/viewtopic.ph ... 5a0e99fa1c

Also, what is up with the grid of V2 being connected to the input jack? Is that just to ground V2 when nothing is plugged in? Less idle noise?

Thanks

[martin manning]

I hope Cliff won't mind if I answer in his stead... Lead mode takes signal from the reverb driver tube's plate, which is created by the load resistor between the power supply's "B" node and the reverb driver transformer's primary. This signal is bypassed around the reverb tank and recovery stage, and mixed back in at the grid of V3b, at the same point as the reverb recover stage's output. For the normal non-lead mode, the footswitch-activated LDR grounds the bypass signal out. I think you're right about the grounding of V1b's grid for noise reduction.

[Deric]

Martin,

Thanks for chiming in - that makes sense. Might have to rethink this a little as I was planning on going with solid state reverb. Not sure the PT in it can handle 2 more 12ax7s.....

[FUCHSAUDIO]

Anyone want another ? Complete, blown dsp, lights with speaker. $ 75.00 plus shipping. Good project platform. If I don't sell it, I might do a rebuild. There is room for sure...

[RCGPNY1]

Actually, in the last couple of days I conviced Andy to try a pentode (5879) simple front end..volume,6 pos. tone switch...into the PI. We are gonna do 2, as he has the one mentioned in his post.... It will be a Gibsonish tone ,(hopefully) and requires only a handful of parts and 1 more 9 pin socket. Ill be posting pics as I go.

[FUCHSAUDIO]

Should be a fun little project for my "brother" and I

[Deric]

Sounds cool!! Looking forward to seeing it progress.....

I was starting to think a 6v6, solid-state reverb version of a TweedyVerb...

Still not sure....

Beer....

[FUCHSAUDIO]

I might do my Champ ODS mod board on mine, if I can fit it.

Rich wants a little 5879 pentode with rotary tone switch and volume control. Super simple little snot watt. Maybe triode pentode or even cathode bias to make it more vintage sounding....

[M Fowler]

Andy I should find something you really want so I can trade for one of your Champ ODS heads.

[FUCHSAUDIO]

I'm growing old, and finding less and less things "I want"...