What on earth should I call it? (assuming I built it)
The Venom S.E.A. - Shaping Envelope Amplifier? I don’t love it, nor do I hate it.
Seriously Engaging Amplifier?
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Venom Serpents Tooth
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I look forward to the new modules, though it’ll take a creative bit of modular engineering to figure out some ways to sort and nullify polyphonic signals, the poly mute seems like the thing I can understand the best and it’d go well with Envelope City too
i just tried the patch and got some quite pleasant sounds out of it, particularly at low envelope rate and high repeat rate. I think it’s a module that could get a fair bit of use.
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Sorry, completely forgot to reply about the octaver! It works really well. I preferred the sound of an octave up, the low octave works OK as well, but I thought a mix of an octave up and octave down sounded slightly rough, I’ll have to try it again. The overdrive is very sweet sounding as well, although I’d like an option for completely clean signal if possible. Polyphony also works fine, it’s the not the strongest candidate for using polyphonically, but it’s fun to get a signal an octave up, then feed that into further poly effects like comb filters or flangers etc. I made a test patch with an envelope follower which triggers an ADSR to fade in the octaver signal. so when you play a note it starts at normal pitch, then the pitch shifted sound fades in. Haven’t had a change to record a demo, but it’s quite a cool effect.
Thanks!
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Thanks Kyle. That feedback helps
Thanks for checking out Octaver. I hope you weren’t trying guitar chords through the Octaver - sub-octaves would indeed sound horrible. But if you can get polyphony with one clean note per channel then the sub-octaves work well.
Keep the drive low, and it should remain pretty clean.
The envelope follower triggering an ADSR to fade in the different octaves sounds interesting. I’m looking forward to hearing a demo.
I have begun development for the next version (2.16) of the free Venom modules. It will probably take quite some time for release - I have a significant backlog of ideas that I want to include. Note I have decided I will create the hybrid Envelope Generator / VCA / Wave Shaper that I talked about earlier.
The first module that I have created is Bounded VCO - an implementation of Peter Blasser’s Bounds/Bounce oscillation concept. The slopes of an oscillator wave remain constant, and the frequency changes as the min and max (bounds) change. See the following thread for more info and some emulations created by existing modules:
Here is the module as it currently stands.
The binaries for v2.16.dev1 are available below to anyone with a free GitHub account
No documentation yet, so I will briefly describe the controls and ports. All parameters have a main knob plus a CV input with attenuverter. The attenuated CV is always summed with the main knob value.
Note - the module is fully polyphonic!
SLOW button - puts the module in LFO mode if enabled. The module runs at audio rates by default.
OVER button - Typical oversample options for Venom modules: Off, x2, x4, x8, x16, x32
SWAP button - If enabled then automatically swaps the Floor and Ceiling values if the Floor rises above the Ceiling. If Swap is not enabled then the oscillator simply tracks the Floor if the Floor rises above the ceiling, rather than bouncing between the Floor and Ceiling.
FREQ - Specifies the frequency of the oscillator when the bounds are constant with 10V peak to peak oscillation. The CV is scaled 1V/Oct
SKEW - Specifies the shape of the oscillation, ranging from decending ramp at 1%, triangle at 50%, and ascending ramp at 99%. The numeric value represents the percentage of the wave cycle devoted to the rising portion of the wave. The fall is simply 100% - skew%. CV is scaled 10% per volt
The Freq and Skew values are enough to specify the rise and fall slopes.
FLOOR - Specifies the minimum voltage for the oscillator
CEILING - Specifies the maximum voltage for the oscillator
TRI - The primary “triangle” output showing the oscillator bounce between the floor and ceiling. Although the shape need not be a traditional synth triangle waveform, it always is a triangle from a geometric standpoint. Afterall, a saw wave is simply a right triangle.
PULSE - Outputs a bipolar pulse wave with +5V high whenever the TRI output is rising, and -5V low when the TRI output is falling.
Here is a simple demo image showing the module in action. The left trace is with the Swap disabled. The right trace is with the Swap enabled. Yellow is the ceiling trace, red the floor, and green the bounded oscillation. The blue is the pulse output.
I am very happy with the results. I have managed to emulate the IFM Fourses module using four copies of the Bounded VCO.
I would love some feedback, especially from anyone that has experience with the Bounds/Bounce oscillations in the Ieaskul F. Mobenthey or Ciat-Lonbarde lineup.
Note that the Bounded VCO algorithm is more sophisticated than the simple slew I used in the prototypes with existing modules. Slew simply places the triangle at the current bound value when an intersection is detected. The module actually computes where the true intersection is using the current slope, and then places the triangle at the correct bounced value using the reflected slope.
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Would you mind sharing a screenshot (and/or patch)?
Fourses Emulation.vcv (3.5 KB)
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And here is a version demonstrating polyphony! The Freq and Skew for the bottom and mid low oscillations are constant. The mid high has different Skew values, and the top has different Freq values.
I discovered I have some work to do - I sometimes get NAN on one or more outputs, in which case I need to reopen the patch. So I need to prevent the NANs. I also need to put a lower limit on the Freq to eliminate the possibility of stalling.
Polyphonic Fourses Emulation.vcv (4.2 KB)
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Super interesting stuff, I went reading thru the Mobenthey modules descriptions. Funny how blasser can be poetic and technical in the same sentence. This is fun to find new sounds and concepts to grapple with, thank you for your work.
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I have the whole IFM lineup … unfortunately I am pretty busy at the moment. But I will give it a try and report back asap.
So happy you are doing this … already having great great fun with the Venjolin (and I have a hardware Benjolin as well 
)!
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If you are open to it, I will DM you sometime in the future with questions about specific behaviors of some IFM modules - the Blasser writeups are inscrutable, and I can’t find any demos that are instructive!
I want to get another free Venom release out with a bunch of modules first, including this basic Bounded VCO. Then I may produce a paid collection of modules that are more closely emulating specific IFM modules and Ciat-Lonbarde synths.
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The Fourses emulation was producing NANS and also producing runaway voltages. Tweaking the algorithm helped some, but did not eliminate the problems.
I think my Bounded VCO logic is good, and the issues are the result of the many feedback paths with their unavoidable sample delays, coupled with floating point limitations. So I put in code to detect NANs and reset values to starting conditions if found. I also clamped the floor, ceiling, and triangle output to +/- 12V.
The Fourses emulation can still produce some wonky values, but they are at least controlled now.
I also implemented a minimum frequency limit to prevent stalling when running at extreme LFO rates.
I think the Bounded VCO behaves well under “normal” circumstances (i.e. without extensive feedback like what is in the Fourses emulation).
You can get v2.16.dev2 with all the recent changes on GitHub
I am hoping that this version of Bounded VCO is release ready. Let me know if you run across anomalies in something other than the Fourses emulation.
Happy to answer questions! I’ll have some time tomorrow to do a comparison between your new Bounded VCO and the IFM Denum / Fourses.
Don’t hesitate to DM me!
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I haven’t tried to truly emulate the Fourses - I was just seeing if I could get the basic functionality. I know there are some computational issues like leaking out beyond the expected voltage range. I hope that putting all computations into a single module will eliminate the anomalies.
I have a true Denum emulation you can test.
Denum Emulation.vcv (4.5 KB)
The 3 dark modules are the Denum UI.
The brown modules are the Denum internals that should be left alone.
The white modules are a simple patch utilizing the Denum.
Of all the IFM module descriptions from Peter - the Denum description makes the most sense to me. I think I got most of the functionality correct, but let me know where I went wrong!
I do have one question - are the linear (caret) inputs truly linear? Or are they just CV inputs that are not affected by the attenuverter? In my emulation they are still exponential, but not attenuated.
I haven’t attempted to match the voltage ranges or frequency ranges.
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Good question … in true Peter Blasser fashion I never really cared much 
but I’ll do a measurement tomorrow. I vaguely remember that I had to use Ableton CV Tools to get Denum tracking v/oct and I think I had used the caret input therefore. By the way, I think Denum’s quirky VCA is something you should consider emulating as it is part of the “secret sauce” of the IFM philisophy. CrucFx did a version of Denum without the VCA and he open sourced the schematics … if that helps.