Divide Down Architecture / Building a Solina String Machine

#1

Hi AxoloFriends!! :smiley:

I would like to build an hybrid String Machine with raw waveforms generated by the Axoloti and an analog JH Triple Chorus as the Ensemble effect.

My deep wish would be to sound as close as possible to the Eminent 310U and/or the ARP Solina.

These two instruments roughly share the same Phase Locked Divide Down architecture. A single master oscillator generate a high frequency Square Wave that is divided down into octaves. The resulted square waves are then filtered and clipped to get the "puls-ish" waves below. I believe the main difference between these two machines is a matter of low pass filtering on the raw waveforms before the ensemble effect

Architecture.jpg1280x720 59.5 KB

Achieving these kind of waves from square waves wasn't too difficult but the major difficulty is to emulate the "phase lock" architecture.

Mr Tiar (aka Smashed Transistors) already helped me a lot and provided me a patch made of 12 phasors feeding a phase selector that allows to get phase locked sinus waves. I’m also in contact with the creator of an amazing Reaktor emulation of the Eminent 310U (https://www.native-instruments.com/fr/reaktor-community/reaktor-user-library/entry/show/4923/) who also helped with the filtering.

With all these information, I managed to modify Tiar’s code and built the patch below which sounds exactly how I want!! …. but with a maximum polyphony of 4 :sob:

(Don't blame me, I didn't find out how to share my library, this is why I also uploaded the 2 .axo objects needed to my patch...)

phasorSelect4.axo (1.9 KB)
string2018-3.axh (32.3 KB)
divide.axo (99.3 KB)

I don’t ask for a full polyphony just like the real thing but a minimum of 8 or even 12 would be great ! Can you guys help me to reach this goal?

PS: I’m more a patch guy than a code guy and I'm pretty new to Axoloti, so please be kind with me :smiley:

SEM-3 Synthesizer finished
#2

Hi! I'm looking into porting the JH Triple Chorus from Reaktor to Axoloti; I was wondering whether you've made some way into this already? Perhaps we can cooperate.

#3

Hi,
The JH Triple Chorus is an analog circuit, not a reaktor patch, sorry :flushed:

You'll find more information here : http://jhaible.com/legacy/triple_chorus/triple_chorus.html

#4

Ah I see, thanks for the link. What I'm referring to then is the ensemble effect that's in the "Solina-V String Ensemble v1" Reaktor instrument, which I believe is a digital recreation of the analog JH circuit. It sounds wonderful I think, see/hear https://www.native-instruments.com/en/reaktor-community/reaktor-user-library/entry/show/4525/

#5

I know that emulation and, most of all, I know its creator, Hugo Portillo. A very kind man.
He helped me a lot understanding the architecture he used for both its Solina and Eminent 310U emulation. Unfortunately he never ported any of his work to hardware and he doesn't know Axoloti boards.

I try to replicate the oscillator section of his Eminent V on my board ... but the Axoloti is unfortunately too limited to run it polyphonically... :cry:

#6

Alright... well not to take anything away from your (in my opinion valid and interesting) pursuit of emulating the oscillator section: have you ever tried running a simple sawtooth through the 3-phase ensemble chorus? To me that sounds close enough, or even better. It reminds me of how the typical Hammond sound is in large part due to the Leslie effect; you can put a sine wave with a little bit of overtones in there and it'll sound recognizable :slight_smile:

#7

Yes, this is of course the first thing I tried when I finished to build the Triple Chorus. It sounds absolutely amazing of course, but I love the "growly" sound of the phase locked oscillators and I needed to emulate it! :smiley: