Hi everyone,

We recently picked up an old moog parametric EQ which we find pretty cool, but we can't figure out what the "drive" pot is supposed to do... we can't find any obvious difference in the sound when turning this pot... is there something wrong with our unit, or are we missing something?

Thanks for your help!
Cheers.

Hate to be the bearer of bad news, but your unit is FUBAR. Noon to 3 o clock should be quite obvious. You should see/hear a change in the level, as well as a motorcyle-like distortion. If you open the unit, you should see the schematics inside the unit. Best of luck.

my drive doesnt "work" either... and i have taken it into Moog and showed them. the schematics should be inside. i was going to trouble shoot it at one point and it seems to be a OPAMP chip where the lack of drive is most likely located.

if the unit works otherwise, use the EQ as the drive is simply a distortion knob.

The EQ actually works, but a distortion knob could be useful... hopefully, the guy who sold it to us is a nice person and he has 2 more units, so I can still change it!

Gotta try the other ones! Anyway, guys, thanks for your help!

BTW, alphajerk, do you remember which OPAMP chip was dead?

Hey e-cue,

Found a second unit, same problem...

What do you feed your unit with? Do you send a very hot signal to it for the drive to work? Which level?

Thanks!

The drive has no big effect on the sound, found this at harmony central.

"There's also a gain control and a drive control. The latter tends to confuse many people, because there's no perceived effect on the sound when you tweak it. What the drive control does is reverse the gain structure at the input and output stages for the purpose of improving S/N ratio. Rotating it one direction (I forget CW or CCW) decreases the input gain while increasing the output gain. The only change you will hear is decreased noise, if any."


http://www.harmony-central.com/Effec...ric_EQ-01.html


Hope this helps.

I see... but still there must be a reason for this knob... I mean, they wouldn't have put one more knob if it didn't change the sound, would they? Plus, according to e-cue, it's supposed to give some obvious distortion... e-cue??? where are you?

Sorry for the delay. I've be held up between studio work and personal life.

This must be a very common problem. I've heard several people complain about the same thing on units they had, not just Alpha and your 2 units. Anyway, here's an example:

https://www.gearslutz.com/board/work-in-progress-advice-requested-show-and-tell-artist-showcase-mix-offs/46628-moog-eq-drive-audio-example-post466443.html

I typically set mine between noon and 3 o clock, program material depending and usually use it on a bass mult.


What I find strange is that your's sound like they are completely bypassed or something. If you do get them checked out and/or fixed, be sure to report back your findings. Then again, maybe mine is broke (or was moded), but somehow does what your 2 units, alpha's, harmony central's, and the rest of the free world's doesn't.

e-cue,

I was wondering if you had tried this distortion thing on other eqs than yours? Just to know if it's something special to your unit...?

Hope you dont mind me digging up this old thread but I've got exactly the same problem with the drive control on the Moog EQ. Did any of you work it out?

Hey y'all,
I know this is an old thread but to the best of my knowledge, the drive knob works this way:

There are two pots stacked on the back side of the knob. One is placed before the EQ circuit and the other is after the circuit. Clockwise-wise, they are opposite each other. So when you turn up the "Drive" knob, more audio goes into the EQ circuit and the output goes down. Make sense? So it is a "drive" in function but not exactly an overdrive unless you're doing some pretty radical EQing or if you're hitting the unit pretty hard to begin with. If you're trying to properly gain stage you likely won't hear anything change.

I own two of these puppies and since I learned how to properly abuse them they have gone from my consider selling list to my desert island list. Hope this helps.

-Slick