MXR Flanger doing the flange thing, but it's "lopsided"

[mrsage]

I was picking up a Boss DD-3 from a guy off of some local classifieds, and when I got there, he was like, "Oh, I also have the flanger pedal. $50 if you want it."

Naturally, I jumped at the opportunity. Turns out it's a vintage 1979 model. 

Upside is that it works. Downside is that the flanging is "lopsided"...by which I mean that it sweeps more quickly at one end of the spectrum than at the other end. Does that make sense? I'm accustomed to flangers that sweep up and down at a steady pace...this one stays steady on one end but speeds up at the other end.

Not sure exactly where to start on this one, as I haven't worked much with time-based effects in the past (other than the paint-by-numbers Build Your Own Clone delay).

Any suggestions would be appreciated.

[Steben]

Could be a mis-biased LFO. For example the waveform of modulation (which alters the delay) may be assymetric or the center of the waveform is not biased to the delay advice. Search for the right trimpot inside and tweak it. I don't know the MXR flanger.

[mrsage]

Yeah, my first thought was that it could be a trimpot, but I'm not familar with the MXR flanger, either. I'm not sure which trimpot I would want to adjust...or how to adjust them. It looked like there were three trimpots in there: one white plastic one that was easy to turn (didn't affect the lopsided-ness though) and two with metal screws that didn't turn easily. I didn't want to break anything so I didn't mess with those.

[Mr.Huge]

That's what the original MXR flanger LFO does... crazy. We've done extensive testing here at L6... We had 3 or 4 originals and they all did the same thing.
It's a really strange shaped LFO...


-Mr. Huge

[PharaohAmps]

I'm with Jorge on this one - I've had at least six in my shop since 2002, and they all have that oddball "slant" to the LFO.  Interestingly enough, I have a tomato-red Ross Flanger, which is a clone of the MXR.  It does NOT have the same "slant."  It does have an asymmetrical LFO, but it's much more usable to me.

I don't have a schem to compare, but I'm sure someone does.  I'd be interested to compare.

Matt Farrow

[mrsage]

Funky...

So it's not broken after all?

Sweet. Not bad for $50 then...