Using Two MF-101 for Stereo?

[latigid on]

If the OP is still around, my question is: how do you want to use a stereo filter?

You asked about controlling two 101s from an MP-201. What would you want to control? If you wanted to have envelopes following both channels independently, the filter reacts to the incoming audio, so no extra control is necessary.

If you want to have both envelopes triggered from one channel only, patch the Env. Out on one to Cutoff on another (insert attenuator if desired).

If you wanted the Voyager "spacing" control that EricK described, you could probably just offset the cutoff frequency for each filter. A trigger delay might be a bit different.

If you wanted to simultaneously alter parameters on both units, you would use a multiple to split CV or expression pedals. The MP-201 might be better for adjusting many controls at once or changing parameters at different rates/depths etc.

Hey, you do have "stereo" hands, don't you?

[hieronymous]

You say that like it's a good thing. Thread drift gets old in my opinion, especially if the original poster's question gets completely ignored.

This post would be so much more worthwile if the person who posted it would have had some positive input/suggestions on the original question.

I assume you're referring to me? I'll go even further and say that it helps if the original poster would revisit the thread and respond to the various questions!

[GregAE]

Post subject: Using Two MF-101 for Stereo?

Is the only way to create a stereo MF-101 with the MP-201? Is the only way to create a stereo MF-101 with the MP-201?

Thanks

bamse

Bamse,

I assume from your question that you are asking about using two MF-101's to get stereo effects, and not a just a single '101 with a Multi-Pedal (there are ways to create a psuedo-stereo signal from a mono output like the MF-101, and you wouldn't need a Multi-Pedal to do it, but that's another topic.)

By splitting your input signal and routing it to two MF-101's (let's just call them LPF's from here), you have a LOT of stereo effect possibilities. The most basic effect would be to set all controls identically on both LPF's, and then offset the filter CUTOFF on just one (this is same thing that happens when you adjust the 'Spacing' control does on the Voyager - it spreads out the cutoff frequencies creating a stereo effect). Doing this would result in a brighter sound on one channel, and a duller sound on the other. Pretty basic, and not terribly interesting by itself.

Now, bringing the other controls into play, you could set one for 2 pole mode, and the other for 4-pole mode. Or adjust one for high resonance while the other is set for little or none (decisions, decisions...).

Adding some envelope filter modulation brings dynamics and interest to the filter sound. If you set the envelope AMOUNT controls identically, the stereo effect would come from the differences in the knob and switch settings of each respective LPF. Or, if you keep the switch and knob settings the same on both LPF's, you could adjust the envelope AMOUNT controls slightly and get some subtle stereo shadings - it really depends on the type of stereo effect you're going for.

Going a bit further, if you have an inverting attenuator handy, you could take the Envelope Out CV from one LPF, invert it, and route it to the Cutoff Input of the other LPF, resulting in contrary response filters; when the cutoff of one LPF goes up, the other goes down, and vise-versa (this technique also works well when an LFO is applied to one LPF while an inverted version of the the same LFO is applied to the other - it sets up a see-saw kind of effect).

Of course, now I'm into the topic of interfacing the LPF with external control voltages (that's what the CP-251 CV Processor and MP-201 Multi-Pedal are for), but you get the idea...

[bamse]

Sorry, I must have unchecked the notifications and forgotten about this thread... ehermmm...

Anyways, I am indeed asking about two MF-101s that I could use for stereo synths or drum machines to create simple filter sweeps of both the Resonance and the Cutoff.

Are there any "expression pedal" knobs out there that I could split? That might be most cost effective.

[latigid on]

Lol, SuperBump! Yup, this thread got a away a bit...

You can use a Moog CP-251 to "split" expression pedals (the 4-way multiple)

[bamse]

Yeah.

I couldn't just use a Y cable for the CV as was mentioned?

[latigid on]

Hi Bamse

I just tried it for you, and yes, you can split an EP-2 with a Y-cable (I just did mine with alligator clips and some connectors).

So you should make (or buy) a cable with a TRS socket and two TRS plugs.

If you wanted to, you could make a "Voltor" box, which basically takes the control inputs and connects them to knobs in an external enclosure. (BTW, I did this myself a few years back so I could control my MF-102 from standing height.)

In your case, if you wire the cables of two units together, you will have one knob that controls both 101s Cutoff, Resonance etc. You could then wire a socket in parallel with this knob, and plug an expression pedal in, and you would have foot control over both parameters. Too confusing?

[bamse]

Hi latigid on,

Thanks for trying the EP-2 with Y cable for me.

Nobody sells the "Voltor" box? I'm not crazy about soldering.

I think I understand what you said. I would prefer the two knobs to one knob or EP-2s. One for Cutoff, another for Resonance.

Any idea how the Sherman Filterbank accomplishes linking with just one 1/4" cable?

[Voltor07]

Voltor box! That's funny! No, no one sells it. It's quite simple for anyone with tools to make one. Perhaps if you found someone who tinkers with electronics to make one for you?

[latigid on]

The Shermans are connected with an insert cable (it's actually wired a little differently than normal).

It's still a mono filter, but with 48 dB/oct
Only one of the units has its envelope triggered by audio.

[bamse]

Ok, maybe one day. First I have to get the second LPF.

@latgid.

I see. I always thought people had 2 Shermans for stereo filtering.

[latigid on]

If you can find a used Akai MFC-42, that's a great stereo (or mono) filter. Much softer than Shermans, but have some great options. On the downside, you can't trigger the envelope via audio, only by a MIDI note on message.

[bamse]

There's one on eBay right now for $385 USD.
What I like about the Sherman is that it does extreme effects. Does the Akai do that?

this one sounds very nice too.

[latigid on]

The MFC tends to do much softer/cleaner filtering. The bandpass and notch filters are amazingly "buttery" and you have the separate phaser too. It's resonance starts self-oscillation at about halfway on the knob (depends on which filter pole you have it on). The distortion mode is pretty rough.

The Shermans (I have both MkI and MkII) are much, much better for distortion/FM/high res sweeps etc.. Can you afford two for stereo processing? Or could you do two takes in post production? Most of the knobs send/receive MIDI, so you could tweak on a track and play back the settings on another pass?

Btw, have you seen the Rodec?