MXR M134 Stereo chorus (5 knob)

[Govmnt_Lacky]

Looking for the schematic on this. Cannot find it for the life of me 

Mostly interested in the implementation of the Tone stack on it. Where, how, and why?

Anyone got a linky or a file for a brother? 

[Govmnt_Lacky]

Can anyone else hear the crickets?   

[Scruffie]

I very much doubt it's out there, don't think Dunlop/MXR are too big on sharing these days.

Perhaps though you could e-mail as a 'customer' and inquire as to whether the tone controls affect the dry, wet or mixed signal for your particular gear requirements and then take an educated guess.

[flanagan0718]

This was all i could find. Hope it helps

[Scruffie]

This was all i could find. Hope it helps

That's the old version, it does include internal DIP switch controls for some tonal shaping... but i'm guessing the re-issue is a full redesign.

Reminds me though, would people like to see this as a DIY project? Perhaps through Haberdasher... Quite a large circuit as far as chorus goes and does use the MN3008 which is a little harder to get/rarer than the 3007... switching to 3208 wouldn't be an issue though.

[Govmnt_Lacky]

Thanks but, thats the older 3-knob type without the tone stack. 

I doubt Dunlop will share either. I was hoping that someone would have it locked away in their vault and be willing to share at least on the DL.

Personally I think the tone stack is implemented in the Dry section. From the research I have seen, I have not found a modulation pedal with a tone stack implemented AFTER the wet is mixed in.

[Govmnt_Lacky]

Quite a large circuit as far as chorus goes and does use the MN3008 which is a little harder to get/rarer than the 3007... switching to 3208 wouldn't be an issue though.

Well.. Seeing as Belling was the only manufacturer that was producing the 3208 AND they have stopped making them, I would say that either the 3008, or 3208 are options.

[Scruffie]

Thanks but, thats the older 3-knob type without the tone stack. 

I doubt Dunlop will share either. I was hoping that someone would have it locked away in their vault and be willing to share at least on the DL.

Personally I think the tone stack is implemented in the Dry section. From the research I have seen, I have not found a modulation pedal with a tone stack implemented AFTER the wet is mixed in.

If you look at that schematic, there are 2 DIP switches that were internal on the vintage unit one pre and one post BBD, I think they were for bass boost/cut so they could have taken that idea further... but I just found a gut shot of the new edition that uses a 3207 BBD so... seems to be a complete redesign.

Quite a large circuit as far as chorus goes and does use the MN3008 which is a little harder to get/rarer than the 3007... switching to 3208 wouldn't be an issue though.

Well.. Seeing as Belling was the only manufacturer that was producing the 3208 AND they have stopped making them, I would say that either the 3008, or 3208 are options.

Cool Audio still make the V3208 (which I don't think is plagued by the issues the v3205s were having) although that is in an 8-Pin DIP package so switching between the 14 Pin & 8 Pin package wouldn't be so easy but I should think there's still plenty of BL3208s out there even if production has ceased... they're used by a LOT of companies.

[Govmnt_Lacky]

Thanks for the info!!!

If anyone comes across any good guts shots, documentation, or schematics.... Please let me know. I can't seem to find ANYTHING on this beast!