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source audio c4

I've had my C4 for a few months now. I'd been following it's development last year with keenness. I held off buying a Xerograph specifically for this pedal. Unfortunately it's launch was right in the middle of a lot of personal change for me so it's been hard to find time to integrate it into my rig...let alone program it. So I sold a house...moved into rented...moved location and started a new job...ooo and I got married too. Currently buying a house that's also taking some time up.

So...Over the weekend I got a rare spare afternoon and evening to sit with it and play. I've found that there's a lot about filters that I thought I knew, but it's quite clear that I don't understand and there's a huge curve going on for me. The midi side and programming things like patch changing using my Boss ES-5 and external Midi controlled expression pedals seems quite straight forwards. But the actual sound crafting is proving difficult for me. Or certainly more of a challenge than I expected it to be. I'm struggling with understanding how all the various bits of architecture flow together and in what order. I think my ignorance is driven by not really having such a controllable filter before. My last filter was an MXR BEF, which only has the one mode. On hind sight...I wished I'd tried a SA Manta or I.E Xerograph before I waded into this pedal at full speed. So I appeased my frustrations by delving through the community patches and finding 50 that I like. I'm savvy enough to have now tweaked most of them with additional personal settings. Things like input and output levels to suit my main bass, Midi Expression as an external Modulation (that's taken a while to work out as the best way to add a midi Wah). Things like mapping input vols to the control knobs so they are easier to use in a live setting are kind of easy and straight forwards to work out. But I think I'm a long way from thinking about a sound in my head and knowing how to achieve that sound with the interface. All of the various poles and low passes are a bit confusing for me at the moment and I'm still playing with interfaces' basics.

Has anyone written a rough guide to this pedal yet? I know there's the manual (which I've read many times already).

Have a Xerograph Deluxe, Joshwah, 3Leaf Proton and a few others... There can be a good amount of learning curve to get what you want out of them too. I don't doubt that much of what they have to offer can be done with the C4; at least to the point of 'no one else but me will notice the differences'.

TBH, I had a hard enough time getting a 'straight envelope filter tone' out of the Xerograph that I used it for swept stunt-envelope for over a year before I found a way to do it. Once I did find it I decided that I'd rather have a second filter on my board so I didn't have to twist knobs to do different things. Now I do those plus a few with the C4.

It helps to know what you're trying to design for if you're going that route...For instance, most of the filters I was using were 4-pole so that was my starting point. I also knew what I fed them with, the XD with a fairly aggressive fuzz, the Joshwah is fed by a more conservative OD, a third one I originally used a Fulltone Full-drive.

This block diagram is fairly accurate:
c4-functional-diagram_orig.png



But I'd start out by thinking:
INPUT->VOICE(s) ->ENVELOPE-> DRIVE ->FILTER->OUTPUT

For any straight up envelope filter design. Pawin' through the filter styles and types may take you a bit, but for a basic easy filter I'd pick

VOICE 1 (only) -> PAN all the way left (sends all the signal to one processor) ->use Drive 1 (if wanted) ->Filter 1 -> Envelope 1 (if wanted) .
 
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I'm in a similar boat... paddling. I am working on tweaking sounds rather than starting from scratch. I'm finding that sometimes simpler is better - adding additional voices doesn't always make the patch closer to what I want.
@BurningSkies I've found that simple path works, and that with that, trying different filter types one by one (keeping other settings the same) gives me a starting point and a slightly better understanding of what those filter types do.
 
I'm in a similar boat... paddling. I am working on tweaking sounds rather than starting from scratch. I'm finding that sometimes simpler is better - adding additional voices doesn't always make the patch closer to what I want.
@BurningSkies I've found that simple path works, and that with that, trying different filter types one by one (keeping other settings the same) gives me a starting point and a slightly better understanding of what those filter types do.

Those are sort of the basic components of an envelope filter. But to break it down a bit:

(photos are from the earlier version of the editor, so some stuff isn't quite the same)

***Note, it helps if you've at least roughly set your sensitivity control so you can trigger the filters, even if you're not fully dialed. Use someone elses' envelope preset to do that first.

Start and end here:
C4_Universal.jpg


Input gain you set to your bass. Use the pedal and make note of what the setting ends up being (the numerical value)...start with that number ever time on your Input 1 Gain.

Master Depth With one filter you don't need to mess with this. With two filters it adjusts both but keeps them in scale. Feel free to ignore for single filter design.

Bass & Treble controls screw around with these AFTER you've designed your envelope filter.

Mix: Go all wet when you're designing your filter so you can hear exactly what it's doing...add in dry later, once you've got your filter tone designed.

Low Retain (now a knob): crossover control...split out the low stuff, keep it clean apply everything you're doing in your filter above that point. If your filter had a ton of depth, this may help you not swamp things. Feel like your filter is killin' your low end presence, use this control.

Output Volume: Seems pretty self explanatory. You'll want to adjust this when you're done. I like mine to be at unity or maybe little bit more so it can be present in a live mix in a band.

Next here Find your Voice:
C4_VoicePanel.jpg


-Set Voice 1 to ON (button top left)
-Mono Input 1 (where your signal is coming from). Other options are more for synth use or doing generated tones like octave pedal effects.
-Envelope; on or off, filter without envelope will open or close based upon signal but the envelope lets you shape the filter's opening and closing, fast/slow, swelled volume or ASDR options.
-Destination is where you're directing the signal. No distortion? Go right to filter. Distortion? set for Filter + Distortion
-Processor Pan: There are two processors (distortion/filters) the pan knob directs your signal to one, the other or both. Crank it all the way to the left (Processor 1).
-Level control I don't generally mess with until closer to the end when I'm figuring what levels I want signals to hit other stages.

Simple envelope filter? Turn off ALL the other voices. Feel free to ignore them.

Next up clean or dirty:

C4_Distortion.jpg


If you've chosen to get 'dirty,' this is where you're headed, otherwise skip this step. Make sure first off, it's ON. You'll see that voice one will have the full yellow bar in the little mixer window on the left, the others should have nothing. That's controlled from the PAN control in the Voice panel.

-Drop down: your pick...which distortion, fuzz, OD option do you want. They all sound different, some are brighter or darker or whatever so you do need to check em' with your bass. You may find that once you combine with a filter you like, you don't like it so much and you go back and try some others. Note, filters LIKE harmonic content. You may find dirtying up your tone even just a little gives your filter something to 'grab ahold of' and give you more of what you want.

-Drive: The amount of distortion.

-Clean mix: Wait...this is just like using a distortion pedal, I know what that means.

- Output: Drive goes up (gain) output can come down so you're not blasting the next stage. ;)

Next...the moment you've been waiting for...the filter:
C4_Filter.jpg


...also ON correct? ;) So...here's where MUCH of your sound design is going to come from. You'll still have that Voice 1 on the left hand side filled yellow (getting your voice one feed whether through distortion or not).

-Drop down: Filter types. A TON of options here. If you're replicating something it's good to know what the original design was. Most basic classics are 2-pole, many modern classics are 4-pole but it's well worth pulling through and hearing how they all differ.

-Invert button: Like that funky Bootsy reverse filter that dives? Click it dawg.

-Depth: how much sweep does your filter have. What's the width it will travel from open to close? Set that here.

-Frequency: Sets the overall frequency of the filter play and sweep and you'll find the place you want. It gives you the starting point of if you're going dark and swampy or something more mid-treble heavy. Remember it works in tandem with the Depth control, which will be how MUCH sweep you have.

Q: Resonant peak: This is where you get the filter emphasis. Soft and subtle or quacky or edgy/reedy. Sometimes you have to balance the filter type with the Q to get things to do what you want.

Destination (unknown): Make sure this is set to 'on' too or it's goin' nowhere. Where are you sending the signal when it's all said and done? Pick your outputs here.


Shaping the Envelope to your filter:

C4_Envelope.jpg


Kinda makes sense, looking at it right? We know what the sensitivity control does. Work this with your bass to figure out how to trigger it best for your dynamics.

Drop Down: Audio Input: This is the actual pedal input you're using, most of us will use Input 1 unless you've got other routing things happening (stereo, loops, etc).

Drop Down: Envelope Types: There's a bunch of attack/release options and in name they tell you what the speed knob does. Some of them will control one or the other or both. Time to play around with 'em. There's also some other stuff like Swell (volume swell) and the ADSR (Attack/Decay/Sustain/Release) settings, which are more meant for the Synth stuff but CAN be used with the filters to fun effect. Play around with them and tweak at will.

Gate: Generally used for the Synth and keyed to help the oscillators' functioning.


...now go back to the general/universal controls and tweak. Fuss your wet/dry, adjust your output level. Play with that retain lows & the master bass/treble controls. :)

Done.
 
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So that's for the basics of doing an envelope filter. From there you can start messing around. Send a voice to the second processor...with a different filter or maybe a second envelope scheme. Or how about adding a voice below that and sending it to a filter. Or sweep your frequency of the filter, or the Q, or depth, while you play, etc. I have one that I sweep the filter frequency then I have a couple sine waves happening on two of the voices in the octaves down which are all volume swell'ed into.
 
So that's for the basics of doing an envelope filter. From there you can start messing around. Send a voice to the second processor...with a different filter or maybe a second envelope scheme. Or how about adding a voice below that and sending it to a filter. Or sweep your frequency of the filter, or the Q, or depth, while you play, etc. I have one that I sweep the filter frequency then I have a couple sine waves happening on two of the voices in the octaves down which are all volume swell'ed into.
Extremely helpful! I assume building Octave patches is about the same process? there are some great ones for the C4, but not so much for the Spectrum. I need some more options, so I guess I'll have to build my own!
 
Extremely helpful! I assume building Octave patches is about the same process? there are some great ones for the C4, but not so much for the Spectrum. I need some more options, so I guess I'll have to build my own!

Yep, I've only tangentially dug into that side of things but if you visit the Voice panel then use the drop-downs on the left you'll find the starting point for voicing your pitch shifting options. That's probably where you'll want to start using multiple voices and you can blend them at will and whatever intervals you want.

IIRC some of the other voice options may play in (and you should be able have some LFO control over some parameters, etc.)...again I haven't dug into that side of things but I'd start there.
 
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The options for the voices drop downs:

Stereo Input Mix (direct input to processing)
Polyphonic Pitch 1 & 2 (generates polyphonic pitch shifting to create chords)
Monophonic Pitch 1 & 2 (generates mono pitch per voice)
Saw 1 & 2 (saw wave synth voices)
Sine 1 & 2 (sine wave synth voices)
Square 1 & 2 (Square wave synth voices)
Mono Input 1 & 2 (monophonic tone generators)

So, you're doing an OC-2 clone and want your clean tone plus two voices?

You can use two voices, then the mono-inputs one set them for octave down & one for 2 oct. down rout em to one or both processors forthe distortion and filters to adjust the grain/grit and-or use the filter to adjust the character if you want. Use the master wet mix to adjust the amount of clean you include and adjust the levels of the individual voice levels to fit. Or you could slate a 3rd voice for Mono in 1 and use that as your clean voice instead of the dry mix.
 
Finally looking at picking up a MIDI controller for my C4 and other pedals. I’m strongly considering the Boss ES-5, but think I’ll also need a MIDI-specific host pedal to use for interfacing/saving presets/scrolling presets/etc with the C4 and Meris Enzo. Anyone have direct experience with the Disaster qConnect yet? I like the size and implementation of extra jacks for external control, but maybe should be looking at one of the more standard Disaster controllers instead?
 
Finally looking at picking up a MIDI controller for my C4 and other pedals. I’m strongly considering the Boss ES-5, but think I’ll also need a MIDI-specific host pedal to use for interfacing/saving presets/scrolling presets/etc with the C4 and Meris Enzo. Anyone have direct experience with the Disaster qConnect yet? I like the size and implementation of extra jacks for external control, but maybe should be looking at one of the more standard Disaster controllers instead?

Do you really love the idea or need of all that 1/4" MIDI I/O? That plus only two switches seems like it could be money better spent on other controllers. I ended up with the DMC-3 XL which allows up to four pedals and if you're going to have more there's a DMC-6.
 
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Do you really love the idea or need of all that 1/4" MIDI I/O? That plus only two switches seems like it could be money better spent on other controllers. I ended up with the DMC-3 XL which allows up to four pedals and if you're going to have more there's a DMC-6.
To add more specifics to what I need- I have a Meris Enzo (that requires 1/4” to MIDI), and I believe the qConnect is the only smaller Disaster controller that has multiple 1/4” Smartjacks so that I can control the Enzo and still have expression control. I also already use a Disaster SmartClock, and utilize it for both MIDI and 1/4” tap-tempo control for non-MIDI and the built-in SmartClock on the DMC-3XL couldn’t give me that non-MIDI tempo control (again it would require an extra SmartClock). It’s possible that the Boss (if I picked one up) could take over the tap tempo control, I have to dig into that more
 
How's that Fuel Tank treating you? Seems like a good fit of specs and nice price for the compact board I'm mulling. So does the polytune2 too, for that matter. And the C4 & DMC.mico setup.

Where'd you say you're stopping on this tour? ;)

The Fuel Tank series is great - quiet, rugged and durable construction. I was actually after the Fuel Tank Classic or Junior when I was buying, but the shop where I was working at the time didn't have it in stock. Took what I could get at staff discount rather than spending full price somewhere else :laugh: I bought the Chameleon to replace a Fuel Tank Junior I fried after a jet-lag induced slip forgetting to switch the voltage on a EU tour. Glad you dig the setup - I'm loving the compact board!
 
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Those are sort of the basic components of an envelope filter. But to break it down a bit:

(photos are from the earlier version of the editor, so some stuff isn't quite the same)

***Note, it helps if you've at least roughly set your sensitivity control so you can trigger the filters, even if you're not fully dialed. Use someone elses' envelope preset to do that first.

Start and end here:
View attachment 3592961

Input gain you set to your bass. Use the pedal and make note of what the setting ends up being (the numerical value)...start with that number ever time on your Input 1 Gain.

Master Depth With one filter you don't need to mess with this. With two filters it adjusts both but keeps them in scale. Feel free to ignore for single filter design.

Bass & Treble controls screw around with these AFTER you've designed your envelope filter.

Mix: Go all wet when you're designing your filter so you can hear exactly what it's doing...add in dry later, once you've got your filter tone designed.

Low Retain (now a knob): crossover control...split out the low stuff, keep it clean apply everything you're doing in your filter above that point. If your filter had a ton of depth, this may help you not swamp things. Feel like your filter is killin' your low end presence, use this control.

Output Volume: Seems pretty self explanatory. You'll want to adjust this when you're done. I like mine to be at unity or maybe little bit more so it can be present in a live mix in a band.

Next here Find your Voice:
View attachment 3592980

-Set Voice 1 to ON (button top left)
-Mono Input 1 (where your signal is coming from). Other options are more for synth use or doing generated tones like octave pedal effects.
-Envelope; on or off, filter without envelope will open or close based upon signal but the envelope lets you shape the filter's opening and closing, fast/slow, swelled volume or ASDR options.
-Destination is where you're directing the signal. No distortion? Go right to filter. Distortion? set for Filter + Distortion
-Processor Pan: There are two processors (distortion/filters) the pan knob directs your signal to one, the other or both. Crank it all the way to the left (Processor 1).
-Level control I don't generally mess with until closer to the end when I'm figuring what levels I want signals to hit other stages.

Simple envelope filter? Turn off ALL the other voices. Feel free to ignore them.

Next up clean or dirty:

View attachment 3592996

If you've chosen to get 'dirty,' this is where you're headed, otherwise skip this step. Make sure first off, it's ON. You'll see that voice one will have the full yellow bar in the little mixer window on the left, the others should have nothing. That's controlled from the PAN control in the Voice panel.

-Drop down: your pick...which distortion, fuzz, OD option do you want. They all sound different, some are brighter or darker or whatever so you do need to check em' with your bass. You may find that once you combine with a filter you like, you don't like it so much and you go back and try some others. Note, filters LIKE harmonic content. You may find dirtying up your tone even just a little gives your filter something to 'grab ahold of' and give you more of what you want.

-Drive: The amount of distortion.

-Clean mix: Wait...this is just like using a distortion pedal, I know what that means.

- Output: Drive goes up (gain) output can come down so you're not blasting the next stage. ;)

Next...the moment you've been waiting for...the filter:
View attachment 3593005

...also ON correct? ;) So...here's where MUCH of your sound design is going to come from. You'll still have that Voice 1 on the left hand side filled yellow (getting your voice one feed whether through distortion or not).

-Drop down: Filter types. A TON of options here. If you're replicating something it's good to know what the original design was. Most basic classics are 2-pole, many modern classics are 4-pole but it's well worth pulling through and hearing how they all differ.

-Invert button: Like that funky Bootsy reverse filter that dives? Click it dawg.

-Depth: how much sweep does your filter have. What's the width it will travel from open to close? Set that here.

-Frequency: Sets the overall frequency of the filter play and sweep and you'll find the place you want. It gives you the starting point of if you're going dark and swampy or something more mid-treble heavy. Remember it works in tandem with the Depth control, which will be how MUCH sweep you have.

Q: Resonant peak: This is where you get the filter emphasis. Soft and subtle or quacky or edgy/reedy. Sometimes you have to balance the filter type with the Q to get things to do what you want.

Destination (unknown): Make sure this is set to 'on' too or it's goin' nowhere. Where are you sending the signal when it's all said and done? Pick your outputs here.


Shaping the Envelope to your filter:

View attachment 3593016

Kinda makes sense, looking at it right? We know what the sensitivity control does. Work this with your bass to figure out how to trigger it best for your dynamics.

Drop Down: Audio Input: This is the actual pedal input you're using, most of us will use Input 1 unless you've got other routing things happening (stereo, loops, etc).

Drop Down: Envelope Types: There's a bunch of attack/release options and in name they tell you what the speed knob does. Some of them will control one or the other or both. Time to play around with 'em. There's also some other stuff like Swell (volume swell) and the ADSR (Attack/Decay/Sustain/Release) settings, which are more meant for the Synth stuff but CAN be used with the filters to fun effect. Play around with them and tweak at will.

Gate: Generally used for the Synth and keyed to help the oscillators' functioning.


...now go back to the general/universal controls and tweak. Fuss your wet/dry, adjust your output level. Play with that retain lows & the master bass/treble controls. :)

Done.
This is a great and in depth write up, thank you :)
Regarding the envelope sections, I feel like what still creates a lot of confusion is the fact that there are two functions of the envelope in the c4: adsr can affect not only the filter but also the amp, i.e. instead of shaping the frequency over time (filter envelope), the amp envelope controls the actual volume of the signal over time. This amp envelope is in that first block where you select the input. It becomes clear that this is affecting the amplitude of the signal when you use the oscillators (sine, saw or square): if you use no envelope, you simply have an immediately loud, long and ever-sustained sound. If you turn on the envelope at this stage, you can control how the sound comes in/attacks (via volume), decays, sustains and releases. The envelope section in the filter part affects the same parameters just not regarding volume but filter.
I thought this might be helpful to point out again. :)
 
What I'm seeing up above (@BurningSkies that is one helluva nice breakdown) is that the Voices are whole sources that can be oscillators like a synth, or something else. Sweet.

As a bit of a synth head, I'll say: filters are by far the most "characteristic" part of what distinguishes a Moog from a Korg from an ARP from a Buchla modular from a Pittsburgh from an Arturia Steiner/Parker from a Dave Smith, etc etc etc. So as y'all (and me/I, soon! once I rebuild my budget YET AGAIN) work on patch building, the more synthy you want to get, the more you want to get familiar with the filter section.

That said... since the Voices are much more than just oscillators (meaning this is much more than just an analog synth in a pedal), they warrant plenty of attention too, since you get the opportunity to do custom bass/synth mixes, which is a dream scenario for music producers of yore.



Also, with four voices comes temptation to always do something with all four. Well! My Korg MS-20 mini has two oscillators, and a number of mono synths out there have exactly one. For a whole lot of synth sounds, one or two are plenty, and a third can be added to do some cool weird effect behind the other two. Or all three for a multi-octave deal, all four for a total pipe organ domination (or utter chaos). Or a mix of dry bass and synth, which is the kind of sound the studio spent a lot of money to create when Anthony Jackson did bass on Chaka Khan's What Cha' Gonna Do For Me, + another cat dubbing over on synth.


Not yet an owner, but clearly I'm excited by the prospect. Just broke for a bit longer, haha
 
What I'm seeing up above (@BurningSkies that is one helluva nice breakdown) is that the Voices are whole sources that can be oscillators like a synth, or something else. Sweet.

As a bit of a synth head, I'll say: filters are by far the most "characteristic" part of what distinguishes a Moog from a Korg from an ARP from a Buchla modular from a Pittsburgh from an Arturia Steiner/Parker from a Dave Smith, etc etc etc. So as y'all (and me/I, soon! once I rebuild my budget YET AGAIN) work on patch building, the more synthy you want to get, the more you want to get familiar with the filter section.

That said... since the Voices are much more than just oscillators (meaning this is much more than just an analog synth in a pedal), they warrant plenty of attention too, since you get the opportunity to do custom bass/synth mixes, which is a dream scenario for music producers of yore.



Also, with four voices comes temptation to always do something with all four. Well! My Korg MS-20 mini has two oscillators, and a number of mono synths out there have exactly one. For a whole lot of synth sounds, one or two are plenty, and a third can be added to do some cool weird effect behind the other two. Or all three for a multi-octave deal, all four for a total pipe organ domination (or utter chaos). Or a mix of dry bass and synth, which is the kind of sound the studio spent a lot of money to create when Anthony Jackson did bass on Chaka Khan's What Cha' Gonna Do For Me, + another cat dubbing over on synth.


Not yet an owner, but clearly I'm excited by the prospect. Just broke for a bit longer, haha

The 4 voices are indeed individual 'sources' of different kinds. Do note though that you won't be able to do more than two of any one kind of Synth voice. So you can layer 2 sine waves but if you want other synth voices you'll have to pick square or saw.

You can mix and match though. I have one patch created right now that has a standard voiced envelope filter with expression swept frequency on voice one, then has 2 sine wave voices, one down and octave and one down two. They're leveled in slightly below the envelope to fill things out down deep.
 
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Ahhh, can't wait to get one of these in and deep dive! There's been a bunch of great demos showing bunches of cool sounds, but I want to see what this thing is like to create patches on! It looks so incredibly powerful. Haven't really seen a synth pedal yet with all those options. Actually feels like a full synth for once!
 
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