Can I use a MF Expression Pedal instead of a MOOG 1120 ?

THM · Post by **THM** » Tue Mar 15, 2005 9:26 am

As in the title: is it possible to use a MF Expression Pedal - see http://moogmusic.com/detail.php?main_product_id=82 - as a replacement for a MOOG 1120 pedal controller ?
Or even more specifically: will I be able to control my Memorymoog's filter cutoff frequency via such an "Expression Pedal" (instead of a MOOG 1120) ?
Could be a dumb question, but I have not many experience with pedal controllers - sorry.

[ Sorry mods for posting this in another forum before but I've got no reply there. ]

Amos · Post by **Amos** » Tue Mar 15, 2005 11:54 am

Yes, you can- The EP-1 is wired the same as the original Moog 1120 pedal. Specifically, the tip of the TRS plug coming from the expression pedal is wired to the wiper of the pot inside the pedal (this is the variable return voltage); the ring connection sends the control voltage to the pedal and the sleeve is ground.

THM · Post by **THM** » Tue Mar 15, 2005 12:59 pm

Hey thanks alot - I'm gonna buy one 2nd hand & try it out !!
Cheers.

THM · Post by **THM** » Wed Mar 16, 2005 10:17 am

Just got an email with this:

Saw your topic on the forum about the 1120/ep-1 compatability - you got a wrong answer - the ep-1 uses a trs plug - ring is voltage supply from the device (+5 V) and tip is CV return to the instrument. Memorymoog does not to my knowledge have a ring voltage supply on the CV in jacks - the 1120 got its CV from a battery, so it produces a cv without external gear...
I don't know of an expression pedal currently in production that produces a CV on its own.

I'd better take no risk and look for a MOOG 1120, isn't it !?

Thanks anyway for the reply.

toryjames · Post by **toryjames** » Mon Jan 21, 2008 2:12 am

Does anyone know how to modify the EP-1 or EP-2 to put out it's own voltage? The 1120 used a 9-volt battery, I imagine the internal components were pretty minimal. Does anyone have a schematic for the 1120? Thanks.

EricK · Post by **EricK** » Mon Jan 21, 2008 2:54 am

heres a link to someone who might provide you with one but perhaps for a fee.

Eric

http://members.aol.com/DBmElect/moogtm.html

SteveD · Post by **SteveD** » Wed Jan 23, 2008 6:00 pm

The 1120 has a battery and a 1/4" Tip-Sleeve output jack

The EP-1 or EP-2 is a passive device - it has a TRS plug - the ring gets +5Volts from the device (moogerfooger, voyager, or LP) - it's the "send", then that goes to one side of a pot inside the pedal. The wiper of the pot then varies from 0 Volts (heel position of the pedal) to +5 Volts (toe position of the pedal) as the pedal is moved. The wiper of the pot is the tip of the plug - the "return" to the device.

So no you can't use EP1 or EP-2 w/ vintage moog gear...but you can use the 1120 w/ modern moog gear...

Hope that clears things up.
SD

EricK · Post by **EricK** » Wed Jan 23, 2008 7:19 pm

Yeah he's right about the EP1 not controlling the vintage stuff. I got the Ep1 and a MicroMoog and while it WILL control the pitch of the osc and the filter cutoff, its not by an amount that will do any good as its only a fraction of what one woudl want and generally not worth the effort.

If one happens to have a REVERSABLE ATTENUATOR in between the current pedals and the vintage stuff then that would be possible.

Also, the vintage stuff is not capable of effectively getting the carrier osc of my MF-102 to track the pitch of the keyboard to the correct scale due to the lack of an attenuator. (even though my Micro has an attenuation pot, its not enough)

(Correct me if im wrong but the current stuff is 1V per Oct while the Vintage stuff is -5V to 5V?)

Eric

Maskin · Post by **Maskin** » Wed Jan 23, 2008 9:36 pm

Besides Korg, almost all vintage stuff is 1 Volt per octave.
-5V/+5V is the range..

EricK · Post by **EricK** » Thu Jan 24, 2008 1:43 am

Thanks,

Yes I must reverse my position on the reverseable attenuators lololol.

Eric

ColorForm2113 · Post by **ColorForm2113** » Thu Jan 24, 2008 3:01 am

sorry to jack the thread but i figure i would ask it hear since its the topic of discussion... i was just looking at the 1120 on ebay and noticed that there are 2 outputs. one is labled OUTPUT the other is AUX OUT. what is the difference betwwen the 2?

EricK · Post by **EricK** » Thu Jan 24, 2008 4:16 am

According to the pictures description, it just supplies the same control voltage out as the main jack.

Im guessing that means its just an extra jack for a seperate destination.

It said don't plug anything IN that jack though like a mic or line in hehehe.

Hope that answers your question.

Eric

ColorForm2113 · Post by **ColorForm2113** » Thu Jan 24, 2008 4:32 am

oh yeah, heh i just saw that. i guess that pic didnt load the 1st time around

eric coleridge · Post by **eric coleridge** » Thu Jan 31, 2008 11:57 am

bosshog wrote:Does anyone know how to modify the EP-1 or EP-2 to put out it's own voltage? The 1120 used a 9-volt battery, I imagine the internal components were pretty minimal. Does anyone have a schematic for the 1120? Thanks.

This would not be difficult or complicated. But, it's even easier to use an un-powered volume pedal a la Ernie Ball, etc. You can just wire a 9v battery connector to a 1/4 inch jack-- positive (red wire) goes to tip of jack, - (black wire) goes to sleave/ground of jack. This just sends 9volts through volume pedal (attentuator) and into your CV input.

The 1120 actually uses 2 9v batteries, I believe, so that it can send both positive and negative voltage sweep. Many CV inputs require a +5v to -5v sweep in to get the full range of the control. This can be accomplished also DIY.

If the EP2 has an attached cord like the EP1, I guess you'd have to split open the cable in order to solder your battery to the input of the attentuating pot (inside the pedal)