Thank you for answering 
Creating a bunch of textures with my patch seems indeed not easy and i played for hours with it… Now i get your patch and i try to learn something more.
Cool. The link for the After Later Audio Eurorack Benjolin manual in the opening post is really instructive and translates well to my patch. Not only did it help me immensely when building the patch, it also helped give me ideas on how to use it. Then once I got a comfort level, it was time to freely explore. The YouTube reviews in that post are good as well.
Of course stoermelder plugins are irreplacable! Hoping to see them in the library soon.
In the meantime I’ve seen some people (including Omri) replace GLUE with some of these modules. Its not the same as having the label directly on the module, but it does the main job which is remembering which knob / module does what =)
Rip Rob Hordijk.
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Thanks for sharing that tragic news. I only just discovered who he was this year, and was thinking I might contact him - opportunity lost. I was intrigued by what I read about him and his designs.
Darn that is too young to die.
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I finally have released my much improved Benjolin patch version 3 that features the great Mind Meld Patch Master to create a clean user interface. It also adds a new Resonance CV input to the patch bay. The demo video shows how the resonance CV can produce some really satisfying swells.
Most of my Benjolin videos show static patching and settings, but it is great fun to play this patch live. It pairs well with a midi controller. I’ve used this patch quite a few times at a monthly experimental music gathering in Baltimore called the Volunteer’s Collective - The patch is definitely a hit.
There are extensive notes about the patch on Patch Storage.
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Hi Dave. This looks cool. I started to download the patch(es) from YouTube a few minutes ago but am confused about how to install. The download is a zip file that contains multiple things. Into what directory should I extract the zip? You may have explained this at some point, but I seem to have missed that.
Thanks
It doesn’t matter where you put the zip file. It just contains two VCV patches, as well as one selection. Just expand the zip file contents to wherever you store your patches and/or selections. The only reason I used a zip file is because PatchStorage does not allow you to upload multiple files, so I needed to package them into one container.
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Thanks.
oh what a fun patch, playing with the Resonant one, and wow, so many different sounds to be found, and the patchmaster interface is excellent. Still not quite have head around how this works, but working on it (and yes, I did RTFM for a change 
)
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Yes! The Benjolin is a BEAUTIFUL BEAST!
Wonderful patch. Thank you very much
As I am also investigating and experimenting with shift register based instruments and I am noticing one big difference with your patch and my personal benjolin patch:
For the “127 steps” mode I switch to a “linear feedback” mode. So instead of xor-ing bit 8 at the input (the 8|16 mode) the input is xor-ed with an extra xor of bit 7 and 6. This will result in a maximum sequence of 127 steps. For those interested, you can read an introduction on LFSR at Wikipedia: Linear-feedback shift register - Wikipedia
It is an elegant modification -just one xor gate extra, so you don’t have to use all those modules for a 127 step loop.
Anyway, thanks again and I love the Unstabile filter: it really shines in your patch.
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Oh wow! I had now idea. That is a huge simplification, and much more elegant - thanks!
I always thought the 127 gate shift register was a rather brutish solution - I was surprised at the design. Now it makes perfect sense.
Yes, that Vult Unstabile filter creates magic!
Someday in the not too distant future I want to create a Benjolin (Venjolin!) module for VCV. I am confident I can handle the oscillators and rungler, but I am concerned about my ability to create a worthy filter.
I look forward to when I have the module created - I haven’t talked about this, but the VCV LFOs I use in my patch of course suffer from wicked aliasing in the audio range. I will simply implement over sampling, which should work great with the max frequency of only 8000 Hz. That should make the end result even closer to actual hardware.
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Looking forward to it!
And yes, the filter is an interesting one:
I have read some info on it on the original forum where the DIY schematics of the Benjolin was shared by Rob Hordijk https://electro-music.com/forum/viewtopic.php?t=38081
He also mentiones his article in Leonardo Music, which is a really nice read! It is mainly about the infamous Blippoo Box -which I am currently patching up, but in the end he writes on the filter and its all-harmonic distortion. Hordijk Rob (2009) The Blippoo Box - A Chaotic Electronic Music Instrument, Bent by Design.pdf (2.5 MB)
For the oscillators I am using 2/4 Pony VCO’s from Befaco. They have great oversampling and I hardly notice aliassing, only in very extreme settings you can hear some. I tried a lot of settings and found a way to give it a huge continuous range (60sec - 10kHz) without giving it extreme CV values.
Oh wait, why write so many words when I can share my patch as well?
Let me clean it up a bit and I will post it in this thread if you like.
Yes please!
I guess you are using 4 Ponies, and I’ll be interested to see if you sync the pairs to maintain a consistent phase relationship between the triangle and pulse.
I use 4 ponies indeed, which are synced when the patch is loaded by BogAudio 4MAN. I checked many times, and they stay in sync, when feeded the same CV.
In the patch I also exprimented with so-called tolerance: in hardware there is an amount of tolerance of components, even high quality components deviate a bit (about ± 0.5% from the stated value) Also there is a slight deviation in circuits, causing drift etc etc. This is also very tiny, but when added up, it gives hardware it’s instabilities, making it work less clean. I tried to emulatie this with not mixing perfectly (so e.g. 99.7% instead of 100% etc etc) and injecting a very very tiny amount of Walk in some paths. I kind of like the result. But you will notice that the math is not perfect. This is on purpose.
I am not yet happy with my resonance settings in the patch. Still investigating
I hope you like it! And I am curious of your opinion!! I added a text file of all the modules used as well
[files are removed: an updated version can be found below]
EDIT: I run my patch in 96kHz Engine rate normally because of the extreme FM going on in the patch
I’ll see if I have time to look later tonight. Right now I need to sign into my weekly Virtual Open Mic!
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many thanks!
I noticed a small error in my patch: as I was experimenting with the PWM signal I accidentally left a DC blocker at the wrong place. Here is an updated version, also with a bit improved resonance behaviour and a corrected fine control. These I use mainly with my midi controller -the range of the oscillators are too large, so you will hear the 128 steps of the 7-bit midi signal.
ROB HORDIJK_BENJOLIN_2.vcv (14.8 KB) ROB HORDIJK_BENJOLIN_2.txt (1.2 KB)
NOTE: Because of the unfortunate inprecise performance of patchmaster since the update 2.3.0 of VCV, some controls are not working as intended. In order to have 0% mix of a parameter, you have to double click on the control. I have built in a workaround for the “input” and “change” knob as well, as double clicking does not work. I made a sort of deadzone at the end of the knobs, so it reaches its min/max range sooner. Maybe I’ll keep these in, as they have become more performable with my controller.
It took me a while to figure out the huge difference between our Benjolins - your resonance is restricted to between 85-99% (actually maxes out at 98%?) Whereas mine goes from 0-97%. Also your drive is significantly lower, and your default cutoff significantly higher. It took me a long time to figure out how to get comparable sounds But I finally got there.
I find I am able to discover interesting sounds more readily with mine, but I don’t know if that is because I am more familiar with it, or if the filter settings really make that much difference.
I see you have a non-linear oscillator frequency response curve via shape master. I simply scale my oscillator frequency CV by 92%, and set the frequency knob to max out at ~8060 with 10V CV (before scaling). My CV range is +/- 10V. That seems to give an oscillator range that adheres closely to the After Later Audio spec, and is definitely not 1V/Oct.
I have reworked my Benjolin to use the linear feedback mechanism - I love it!
I have also created a version where I can switch between which oscillators are used.
- VCV LFO
- Befaco Pony in LFO mode (all x8 oversample)
- Befaco Pony in VCO mode (triangle x2, pulse x8 oversample)
I use the Count Modula Startup Delay to automatically send a sync pulse to the VCOs one second after the patch loads. I also added a manual sync button, but as you say, the Ponies do a great job remaining in sync, so I don’t think the manual button is really needed.
I think the Pony VCO mode includes a BLEP treatment (or whatever, I’m not fluent in DSP), whereas the LFO does not. But both are oversampled,
I was able to configure them so their frequencies nearly match perfectly, so comparisons can be made, and I am shocked how little difference there is in the final Benjolin output.
If I listen to the raw pulse output at high frequencies, then of course I hear tremendous aliasing out of VCV, much better (less) out of Pony LFO, and hardly any aliasing out of Pony VCO unless I go extremely high. (I’m running Rack at 48 kHz)
But typically with the Benjolin you are listening to some amount of the PWM and/or XOR signals, and they are not anti-aliased. So the differences between the oscillators largely disappear, even at high frequencies. Both Pony configurations generally are smoother in the high register, and the VCV is a bit grittier (which I happen to like). If/when I create my own Benjolin module, I will look into having an option to oversample pretty much everything, including the shift register, comparators, and logic gates. It will be interesting to see what effect that has.
Here is the patch to compare the oscillators. It is configured the same as my prior resonance CV swell video, except I raised the frequency to highlight the oscillator differences better. I’ve included the delay and reverb (not too much), but it is easy to hit the bypass button on the delay to kill both if you want to hear the raw Benjolin.
Benjolin V4 Resonance CV Demo Osc Compare.vcv (9.2 KB)
And here is the same patch with some different settings that produce some absolutely gorgeous drones.
Benjolin V4 Beautiful Drones.vcv (9.2 KB)
I was thinking my next “official” Benjolin patch release would use the Pony, but after these results, I think I may just stick with the VCV LFO - no worries about triangle/pulse sync, and less CPU.
It would be wonderful if there were a anti-aliasing comparator in VCV! Many times I reach the (digital) limit of VCV, having to run my patches in higher sample rates with big CPU. I will check your patches out! And I think you are right concerning the small difference when not running in extreme modes.
I totally forgot to “tune” the filter! Thanks for the reminder.
As for the non-linear frequency response: I started with listening to the oscillators of the Blippoo Box and their 0V frequency is around 20-32Hz. The range of the Blippoo oscillators are not specified, only that they go up to 12 kHz. With a range of -9V to +9V you get the 18 octaves Rob mentions in his articles/interviews.
But this was just too much to handle for the comparators etc in VCV, so I compressed the upper range, but retaining the division of LFO/VCO range on the knob: Pure cosmetics 
I just copied this oscillator to the Benjolin patch.
You are right there is hardly any difference between the VCV LFO and the Ponies in the low range. But as I do a lot of sound design and use all kinds of chaos/noise etc, I am also very interested in the high register. Hence my choice for the Ponies: they really make a difference (especially at 96kHz) there. I am lucky with having a powerful MacBook M1 which can handle the CPU very well…
Thank you again for checking out my patch!