BOD->Fatman = annoying ring???

[ninepoundjammer]

Just got in a MXR Bass Octave Deluxe, added it to my board and noticed an annoying ringing when I had my WMD Super Fatman envelope filter turned on. Did some trouble shooting and here's what I found:

Bass->Fatman(on)->amp
sounds fine

Bass->BOD(bypass)->Fatman(on)->amp
slight ringing

Bass->BOD(on)->Fatman(on)->amp
noticeable ringing

Bass->Boss TU-2(bypass)->BOD(bypass)->Fatman(on)->amp
noticeable ringing

Bass->BOD(bypass)->Boss TU-2(bypass)->Fatman(on)->amp
slight ringing

Bass->BOD(on)->Boss TU-2(bypass)->Fatman(on)->amp
noticeable ringing

I've attached an mp3 so you guys don't think I'm crazy. First cluster of notes is just the Fatman, second cluster is TU-2->BOD->Fatman, everything but fatman on bypass.

So, I always get this ringing if the BOD is on, even with a buffer between it and the Fatman (BOD is fine by itself). Crazy thing is that even with the (supposedly true bypass) BOD on bypass, I get the ring, and if I put the Boss TU-2 in front of it, it makes it even worse.

I can believe there's some strange interaction between the octave and filter when they're both on, but how can the bypassed BOD cause this? I'd love to hear an explanation of this from someone who understands electronics better than I do.

[ninepoundjammer]

Nobody?

This is weird and annoying, right?

[Funkinthetrunk]

Tried my BOD before and after the WMD Super Fatty...not ring to be heard.

[ninepoundjammer]

Originally Posted by Funkinthetrunk

Tried my BOD before and after the WMD Super Fatty...not ring to be heard.

Hmm. Thanks for the info.

I haven't had my Fatty that long. I noticed right away it produces sort of a swish in the upper mids at a certain point in the filter sweep, but it isn't that bad and I figured that was just normal. It is something that the other filters I've spent time with don't do though. Just so happens this is the same point in the sweep where this ringing occurs. I'm starting to wonder if there might be some sort of defect in my Fatty. Still don't have a clue how the octave plays into this.

I'll have to play with the Fatty a bit more and see if changing the sweep range and other parameters has any effect.

[Spencer!]

What kind of power supply are you using? See if the ring goes away if you switch everything to batteries.

[ninepoundjammer]

Originally Posted by Spencer!

What kind of power supply are you using? See if the ring goes away if you switch everything to batteries.

Funny thing is, every time I have issues with my pedals, trying running on batteries is the first thing I do, but I was too lazy this time, since in practice it's never solved any of my problems.

Using a One Spot. I know certainly not the best power supply. I switched to batteries and it's the same, if not a little worse.

Also just got my Groove Regulator back (from Spencer! -- the clean blend mod was for me ), and this doesn't happen with it.