Let's solve this! Source Audio expression options

[enjoi1018]

Hey guys, I posted awhile back about trying to get a Moog EP-2 to work with the SB2 pedals as an expression. Roger from SA emailed me personally and they devised a cable (that I'd solder myself) that would convert the 50K pot out in my Moog to the 4-pin connector of the Multi-Function in. They said that it should work, but they didn't test it.

I just spent a few hours soldering and resoldering, and I just can't get it to work at all. It's as if there's not even a pedal plugged in.

There's gotta be a way to do it! The SA dual expression is passive. I'm not positive what pot is in it but even if I had to change the pots I'm my Moogs to work I'd do it. I'm REALLY limited to using the Moog housings though, as I've designed a expression board to their exact measurements.

Any and ALL help is appreciated. I'm gonna keep working on it, but I think this could help out a lot of people who would rather have a a couple of cheap expressions separately than have one or two Dual Expressions at over $200 and/or to control and leave separate settings.

So LET'S SOLVE THIS!!!!

 

[LSMFT6]

This is why I got one of their new Hubs – the midi capabilities are cool, but it also allows you to use any expression pedal with the SB2 line without special cables.

 

[enjoi1018]

This is why I got one of their new Hubs – the midi capabilities are cool, but it also allows you to use any expression pedal with the SB2 line without special cables.

Can you use more than one expression pedal with it? I have two sitting next to each other acting as completely independent adjustments. I don't wanna have to drop down to one pedal.

EDIT: Found it. Only one. That wouldn't be terrible if I could get my other Moog to work with my Zoom B3!

 

[LSMFT6]

Expressionator?

 

[enjoi1018]

Hmmmm. Now with your Orbital coming I'm gonna have to figure this out. I really need to do the research of checkin out the hub or changing my Moogs to work with them.

Hmmmm.

 

[LSMFT6]

I have a Mission dual expression pedal that controls my Manta and H9. Technically there's more I could do with two separate exp. pedals, but I like the practicality of only using one.

 

[enjoi1018]

and I'm guessing you can only use it with the hub?

 

[NecroticImbecil]

Roger from SA emailed me personally and they devised a cable (that I'd solder myself) that would convert the 50K pot out in my Moog to the 4-pin connector of the Multi-Function in. They said that it should work, but they didn't test it.

:

Could you share the information re: the cable so that someone else could try to make one? Not saying you did anything wrong, but another person would be working with another pedal, etc. Quite likely the same result, but not certain. This would help identify the cable plans (schematic, whatever it is you have) as workable or not. Probably against a rule to post an email but the relevant parts could be cut/pasted, if the instructions were emailed to you.

 

[Skrogh]

I think I did this once, on a breadboard - with one of the older SA pedals; and I see no reason why it wouldn't work. Can you post schematics, pictures of your build - anything?

I have a good idea about how things are supposed to look. do you have a multi-meter at hand?

 

[enjoi1018]

Here is Roger's email to me verbatim:

Hey Travis,

Thanks for using our stuff!!

​​​​​This is from Jesse. See the nice schematic attached.

If he buys one of these:
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and something like one of these:
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and connects them like the attached photo. Should work. Haven’t tested it myself.

 

[Skrogh]

Diagram looks good to me, can you show how you've wired it?
can you verify with a multimeter that you made the correct connections? If you position the expression pedal in the middle you should be able to make the following measurements:
(places to check will be named tip, ring1 ring2, sleeve and are on the small, 4 connector jack you soldered to the ep-2)

tip - sleeve resistance 50k ohm
tip - ring2 open ( inf ohm )
tip - ring1 ~25K ohm
sleeve - ring2 open
sleeve - ring 1 ~25K ohm (or 50K minus the reading from tip to ring1 )

Do this with the pedal connected to noting but the converter.

 

[enjoi1018]

I have tested the cable and it's definitely not working right. Problem is, when you don't buy those little parts in bulk they rip you. $13 down the drain!

I suppose I could give it another go... but I'm not sure. I wish it could be tested. BTW, I've actually modded my Moogs to have 1/4" jacks on the rear rather than the stock cable. They are still wired the same, just wanted to clear that up.

 

[Skrogh]

Ah yes I did that too, and added a stereo pot, 10K so I can use it with my Line6 and SA pedals at the same time.

the 13$ is that for the cable? you should be able to reuse the parts - if that's a problem I can probably find you a place to pickup 4-wire small jacks cheaper. If you can wait for it to arrive from hongkong, you can get them for under a 1$ at ebay. search "3.5mm jack trrs".

If you do the measurements and post results or show some pictures, debugging would be a lot easier. If you are uncertain if it will work when wired correctly - I cannot help as I only have SB1 and PRO pedals.