MXR 126 Flanger/Doubler - similar to 117?

[lincolnic]

I've been wondering about this for a little while, and I figured this was the best place to ask. Does anyone know if the old blueface MXR 126 Flanger/Doubler is a similar circuit to the 117? We have a 126 at my studio, and it sounds fantastic, but I know it's got a SAD1024 in there (along with another rare IC) and I feel like it's only a matter of time before it goes. Does the 117 share any of the flanging circuitry with the 126, or are they very different?

126 schematic, if that helps: https://dl.dropboxusercontent.com/u/33143162/MXR%20M126%20Service%20Schematics.pdf

[selfdestroyer]

Here is the 117 schematic. Might help you compare them.

http://i82.photobucket.com/albums/j279/bainzy007/flangerm117_12.jpg

Cody

[Govmnt_Lacky]

You are correct sir! The other "rare" chip being the R5101 which, compared to the SAD1024, is about as easy to procure as crystalized unicorn tears wrapped in a diamond shell 

[Scruffie]

I'll be honest, i'm too drunk to look at the schematics, but if I recall, the 5101 isn't used for the flanger part and the flanger does share some similarities to the 117 but isn't the same... how different it is though is up to a sober scruffie.

I would bet that a 117 can get many of the sounds though.

[lincolnic]

I'll be honest, i'm too drunk to look at the schematics, but if I recall, the 5101 isn't used for the flanger part and the flanger does share some similarities to the 117 but isn't the same... how different it is though is up to a sober scruffie.

I would bet that a 117 can get many of the sounds though.

To the best of my knowledge, the 5101 is used for the Doubler portion of the 126. Scruffie, once you've sobered up, I'd love to hear anything you've got to say on the subject!

[Scruffie]

The schematic is a pain in the ass to read broken across 2 pages like that but I don't think the 117 is all that similar, the VCO & Clock is certainly different to some degree, I think the flanger and doubler share the same filtering path and there is a lot more filtering going on in that case. But there's nothing particularly special going on I can see so a 117 may still get the same basic sounds.

There's no reason for your 126 to die though, you might need to service the electrolytics and tantalums soon though. But if anything does happen to it, don't just assume the rare BBDs are dead, there's 3 CMOS chips to die too any of which failing could cause the unit not to function.

[lincolnic]

Apologies about the way the schematic is broken up - the only other version I could find was too small to read properly.

I had a hunch that they weren't very similar, but I thought since they both had a SAD1024 at their hearts there might've been some commonalities.

The 126 is behaving perfectly normally, I was just curious about what the differences between the two were. It could probably stand to be re-capped, though it honestly doesn't get used that often. Knowing the way things go in the studio, no one will think about repairing it until it suddenly stops working mid-session. 

Thanks for the insight!

[RobA]

I was able to piece a single page together from the two halves and have it as a PDF. It looks to me like I've got them lined up right. I don't really want to put this up on my own website and I don't have a dropbox or similar account, but if anyone wants it, I can email it to them. PM me if you want me to send it to you.

[lincolnic]

I was able to piece a single page together from the two halves and have it as a PDF. It looks to me like I've got them lined up right. I don't really want to put this up on my own website and I don't have a dropbox or similar account, but if anyone wants it, I can email it to them. PM me if you want me to send it to you.

I'd love to have that, thanks for making it! I'll PM you my email.