Moog MF-101 Alternatives

Apologies for the delay in getting back to this, also for the lack of video/soundclips - been a busier couple weeks than anticipated.

I did however, manage to get some time with a bunch of filter pedals yesterday evening and thought I'd share the findings. Filters in use:

- Moog MF101
- Source Audio C4 (just filter so spectrum could be sub'd)
- EHX Enigma Q Balls
- EHX Cock Fight
- Iron Ether Xerograph
- Malekko Scrutator
- Future Impact
- Line 6 HX FX

TL;DR - there is no real alternative to the MF101. All the other options come with compromises, either lack of controls, limited filter range, not as thick/juicy/resonant....etc.
If colour/character is your primary concern and the 6kHz cap is ok then the C4 will sort you out.
If you need the wide sweep and are ok to have a slightly cleaner filter character, with preamp drive coming elsewhere the Xerograph is the one to get.

SO....
Source Audio C4 - closest of them all in terms of phat filter tones, and the resonance...etc. But you do have that top cutoff cap at 6kHz (@rsmith601 is there any possibility of an update to lift this at all?). Pitch tracking on the filter is really great for static stuff that opens a little with higher pitches. The drive section allows you to cop some of that MF101 preamp clipping and warmth too which is a real win. Obviously a wild range of filter types, that all sound lovely warm and fat. I found adding some exp control of mix allows you to counteract the upper cutoff limit a little by blending in clean as you open up the filter.

EHX Enigma Q Balls - this is the juiciest of them all, and the resonance can get wild. Forgot just how much I love this filter so great to revisit it again. Tweaking of the internal distortion trimmers has achieved a distortion that is more fuzzy-overdrive which is a delightful sound. I was surprised that the filter doesn't fully open, and actually seems to cap out around 3/4kHz.

EHX Cock Fight - it's a wah style so it never really opens up in the same way, which limits the versatility of this pedal. However, I love the character this has for filter sweeps or static stuff, and the "bottom" control is a wonder here. The fuzz in this pedal is wonderful too, and with the bottom control it makes for one of my favourite gated germanium style fuzzes. This pedal is a sleeper (also, for fans of Royal Blood - this nails all the recent album cocked was fuzz tones). It's very much a feature effect the moment it is turned on. Unlike the MF101 which you can have always on with cutoff fully up and sweep as you need.

Iron Ether Xerograph - It has the full cutoff range so can totally open, and resonates wonderfully. It lacks some of the fatness of the Moog and doesn't have any preamp/drive control. It's easy to add a drive pedal here. Limited expression pedal control, but otherwise this is the closest to the MF101 of all those I tried. Although the C4 character gets closer to the bigness/fatness of the Moog. With the Xero feeling like a cleaner filter in general.

Malekko Scrutator - Full frequency sweep on the filter. The bit knob maxed is my favourite synth-y gated fuzz sound and with the filter sweepings is just glorious! The Preamp can also introduce some very pleasing drive and beef, but the lack of output control means things can get very loud very quickly. The filter sounds great, but was the most neutral/clean sounding filter (without preamp or bit pushed) - the others impart a bigger/fatter sound quality. The Scrutator doesn't lose/cut any fatness, it just doesn't add any.

Future Impact - frequency sweep seems to cap out a bit. A touch higher than the C4 but only by a hair. The filter is very flexible and the combo of VCF and BPF allows you to focus on some really interesting harmonics in the filter. I find the filter on this a touch sterile, and whilst it has more fatness/bigness than the Xero/scrutator it feels a touch more flat, and the resonance is quite as lively.

Line 6 HX - The auto filter sounds great, but caps at 1kHz (unless you have env modulation on) which is frustrating. The Asheville Pattern absolutely nails the MF101 preamp tone; it's ridiculous! I may now use this as an always on preamp in the HX moving forward. Sadly no sweepable control at all that allows you to get filter sweeps (@Digital Igloo please can we get a MF101 in the HX format? OR sweepable filter in the Asheville Pattern). Perhaps I'm missing something here... I love the auto filter for standard auto filter bits, but the Helix format lacks a proper sweepable/static resonant LPF currently, which feels like an unnecessary limitation.

I'd be keen to try a Frostwave Resonator clone, as I love the Korg filters.
Also of interest are...
3 Leaf Chromatron
Death By Audio Evil Filter
Triungulo Lab Barbanera seems to nail the MF101 preamp and filter from what I can tell in demos, so is worth hunting down too. That may be the ultimate answer I think.

You can obviously also go down the Eurorack wormhole too, and this is certainly the only clear way to achieve the same functionality as the MF101, but you obviously have to then deal with integrating that within a standard pedal board. I previously owned a Pittsburgh Patch Box which I used for this purpose, but he power supply/rails suffered noise and bleed between modules. These days I just use a euro rack pedal interface module to allow that all to play well together. Though that is only a studio setup for me.
 
Apologies for the delay in getting back to this, also for the lack of video/soundclips - been a busier couple weeks than anticipated.

I did however, manage to get some time with a bunch of filter pedals yesterday evening and thought I'd share the findings. Filters in use:

- Moog MF101
- Source Audio C4 (just filter so spectrum could be sub'd)
- EHX Enigma Q Balls
- EHX Cock Fight
- Iron Ether Xerograph
- Malekko Scrutator
- Future Impact
- Line 6 HX FX

TL;DR - there is no real alternative to the MF101. All the other options come with compromises, either lack of controls, limited filter range, not as thick/juicy/resonant....etc.
If colour/character is your primary concern and the 6kHz cap is ok then the C4 will sort you out.
If you need the wide sweep and are ok to have a slightly cleaner filter character, with preamp drive coming elsewhere the Xerograph is the one to get.

SO....
Source Audio C4 - closest of them all in terms of phat filter tones, and the resonance...etc. But you do have that top cutoff cap at 6kHz (@rsmith601 is there any possibility of an update to lift this at all?). Pitch tracking on the filter is really great for static stuff that opens a little with higher pitches. The drive section allows you to cop some of that MF101 preamp clipping and warmth too which is a real win. Obviously a wild range of filter types, that all sound lovely warm and fat. I found adding some exp control of mix allows you to counteract the upper cutoff limit a little by blending in clean as you open up the filter.

EHX Enigma Q Balls - this is the juiciest of them all, and the resonance can get wild. Forgot just how much I love this filter so great to revisit it again. Tweaking of the internal distortion trimmers has achieved a distortion that is more fuzzy-overdrive which is a delightful sound. I was surprised that the filter doesn't fully open, and actually seems to cap out around 3/4kHz.

EHX Cock Fight - it's a wah style so it never really opens up in the same way, which limits the versatility of this pedal. However, I love the character this has for filter sweeps or static stuff, and the "bottom" control is a wonder here. The fuzz in this pedal is wonderful too, and with the bottom control it makes for one of my favourite gated germanium style fuzzes. This pedal is a sleeper (also, for fans of Royal Blood - this nails all the recent album cocked was fuzz tones). It's very much a feature effect the moment it is turned on. Unlike the MF101 which you can have always on with cutoff fully up and sweep as you need.

Iron Ether Xerograph - It has the full cutoff range so can totally open, and resonates wonderfully. It lacks some of the fatness of the Moog and doesn't have any preamp/drive control. It's easy to add a drive pedal here. Limited expression pedal control, but otherwise this is the closest to the MF101 of all those I tried. Although the C4 character gets closer to the bigness/fatness of the Moog. With the Xero feeling like a cleaner filter in general.

Malekko Scrutator - Full frequency sweep on the filter. The bit knob maxed is my favourite synth-y gated fuzz sound and with the filter sweepings is just glorious! The Preamp can also introduce some very pleasing drive and beef, but the lack of output control means things can get very loud very quickly. The filter sounds great, but was the most neutral/clean sounding filter (without preamp or bit pushed) - the others impart a bigger/fatter sound quality. The Scrutator doesn't lose/cut any fatness, it just doesn't add any.

Future Impact - frequency sweep seems to cap out a bit. A touch higher than the C4 but only by a hair. The filter is very flexible and the combo of VCF and BPF allows you to focus on some really interesting harmonics in the filter. I find the filter on this a touch sterile, and whilst it has more fatness/bigness than the Xero/scrutator it feels a touch more flat, and the resonance is quite as lively.

Line 6 HX - The auto filter sounds great, but caps at 1kHz (unless you have env modulation on) which is frustrating. The Asheville Pattern absolutely nails the MF101 preamp tone; it's ridiculous! I may now use this as an always on preamp in the HX moving forward. Sadly no sweepable control at all that allows you to get filter sweeps (@Digital Igloo please can we get a MF101 in the HX format? OR sweepable filter in the Asheville Pattern). Perhaps I'm missing something here... I love the auto filter for standard auto filter bits, but the Helix format lacks a proper sweepable/static resonant LPF currently, which feels like an unnecessary limitation.

I'd be keen to try a Frostwave Resonator clone, as I love the Korg filters.
Also of interest are...
3 Leaf Chromatron
Death By Audio Evil Filter
Triungulo Lab Barbanera seems to nail the MF101 preamp and filter from what I can tell in demos, so is worth hunting down too. That may be the ultimate answer I think.

You can obviously also go down the Eurorack wormhole too, and this is certainly the only clear way to achieve the same functionality as the MF101, but you obviously have to then deal with integrating that within a standard pedal board. I previously owned a Pittsburgh Patch Box which I used for this purpose, but he power supply/rails suffered noise and bleed between modules. These days I just use a euro rack pedal interface module to allow that all to play well together. Though that is only a studio setup for me.
I am checking into the filter question. Glad to hear that the C4 does so well! :)
 
EHX Enigma Q Balls - this is the juiciest of them all, and the resonance can get wild. Forgot just how much I love this filter so great to revisit it again. Tweaking of the internal distortion trimmers has achieved a distortion that is more fuzzy-overdrive which is a delightful sound. I was surprised that the filter doesn't fully open, and actually seems to cap out around 3/4kHz.
The part I bolded and underlined is the dirty little secret about the Q-Balls. Because you can set the Start/Stop controls to provide no sweep (both knobs at 11:00, 12:00, 1:00, etc.), you can engage the distortion and get a big variety of cocked/fixed/stuck/parked wah tones. I like it so much that I had the distortion trim pot modded to the outside, which also lets me add a touch or a ton of overdrive/fuzz to the envelope. And the blend control just makes it that much more versatile. BTW, those cocked/fixed/stuck/parked wah tones also sound great without the distortion.

The Q-Balls is my favorite envelope filter, but it's also a really good dirt pedal.
 
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The part I bolded and underlined is the dirty little secret about the Q-Balls. Because you can set the Start/Stop controls to provide no sweep (both knobs at 11:00, 12:00, 1:00, etc.), you can engage the distortion and get a big variety of cocked/fixed/stuck/parked wah tones. I like it so much that I had the distortion trim pot modded to the outside, which also lets me add a touch or a ton of overdrive/fuzz to the envelope. And the blend control just makes it that much more versatile. BTW, those cocked/fixed/stuck/parked wah tones also sound great without the distortion.

The Q-Balls is my favorite envelope filter, but it's also a really good dirt pedal.
Dang I’m always surprised how often I feel GAS for an EHX pedal! For some reason I never tried one of these outside a noisy store
 
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I feel the HPF is also massively overlooked.
With start and stop frequency set low in the range, and resonance set pretty high; you can pull off a sub harmonic boost that can be earth shattering. Similarly with a relatively wide sweep in this setting and fast attack/decay times you can add some percussive/punchy sub sonic attack to notes as well.
 
I know this thread is about 101 alternatives, but curious for the fellow 101 owners out there, how do you handle the volume drop with higher resonance? It is subtle, but this circuit reduces volume when resonance is turned up. I like the resonance around 7, and this causes a subtle but noticable volume drop from bypass to engaged.
 
I know this thread is about 101 alternatives, but curious for the fellow 101 owners out there, how do you handle the volume drop with higher resonance? It is subtle, but this circuit reduces volume when resonance is turned up. I like the resonance around 7, and this causes a subtle but noticable volume drop from bypass to engaged.
I think basically the only solution to that would be to put the 101 in a bypass loop and turn up the drive. Or turn down the resonance but then you don't have exactly the tone you're looking for. I keep the resonance on mine at around 4-5 so the volume drop isn't as noticeable.
 
I know this thread is about 101 alternatives, but curious for the fellow 101 owners out there, how do you handle the volume drop with higher resonance? It is subtle, but this circuit reduces volume when resonance is turned up. I like the resonance around 7, and this causes a subtle but noticable volume drop from bypass to engaged.

Boss LS-2 works well to have a post volume (it's volume controls work on the return signal).

Another way is to balance with the mix knob, which works to a point. I tend to run mix and resonance around 7-8.
 
I keep the resonance at about 7.5 and there is no perceived volume drop when I kick it on. Granted I use an exp pedal and sweep so various parts of the sweep cut through better than others but since I only use the effect in that way it is never a problem since I always have movement on the cutoff.

Are you using it as an envelope follower?
 
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I keep the resonance at about 7.5 and there is no perceived volume drop when I kick it on. Granted I use an exp pedal and sweep so various parts of the sweep cut through better than others but since I only use the effect in that way it is never a problem since I always have movement on the cutoff.

Are you using it as an envelope follower?
I use it as an env follower and sweepable filter.
 
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