OPERA ROTAS, a DIY mutant drum machine

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SphericalSound
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OPERA ROTAS, a DIY mutant drum machine

Post by SphericalSound » Wed Jun 10, 2020 7:22 pm

Opera Rotas has the weirderst workflow. Even if you can insert and edit notes and parameters one by one, like "normal" drummachines, where the magic happens is when you engage in his "auto" mode. In this mode it performs a kind of parameter lock of the current channel setting, and in every step in jumps to the next channel, editing the parameter that you are currently tweaking. It produces all kind of serendipitous movements and sonic mutations, ranging from techno, to chiptune and sometimes touches of classical mussic and alienesque landscapes.

It´s truly difficult to explain, but dead easy to get into that flow and improvise all kind strange textures and patches. I guess the better way to understand how it works is with a video jam.



At the core it has a real Yamaha OPL2 audio chip. And live sounds bonkers. Brutal, it´s all body, weight while being crystal clear and punchy. Really the videos doesnt do aural justice but it serves to get an idea. There will be coming decent audio demos in my souncloud soon.

The firmware is a work in progress. Too much ideas. One branch of the firmware consist in attaching a midi keyboard to it and convert it in a fully fleged polyphonic synth.

I will open source the beast in some moment, just asking for the people for not to do commercial PCBs of it, as I sell it in my tindie. If you get one PCB or kit you can ask for the source code to tweak it if you will.

An AphexTwinesque sounding jam. All demos are realtime generated, no previous writing of patterns or instruments. It´s all on the fly (this was the previous prototype):



OPERA ROTAS uses a OPL2 board that you have to get separately from his creator and my colleague, Maarten Jansen here or directly at me if I have spares:
https://www.tindie.com/products/cheerfu ... dio-board/

The screen works perfectly even if in the videos you see the flickering of the camera. It is based around an arduino blue pill stm32, so it has a lot of memory and extra cycles to keep developing the firmware.

Currently it has no memory to save states or songs but you can connect it to the USB and do backups here. This part is still in developing. Potentially I could even write an VST to interface it with the DAW, but not sure if it´s happening. I have never written an VST... Maybe if somebody decides to do so.

Potentially is super easy to get an stream of the song played in realtime and save it in the VGM format. This is the native format of the yamaha chips (used, for example in consoles as the Sega Genesis / Megadrive, which is a close cousing of this OPL2. The megadrive one is the OPN2. I will probably write this song capturer in any moment.

Finally, this is the previous prototype with no leds nor screen. It runs on the venerable arduino nano. I have 8 spare PCBs to sell if somebody wants to build this version. It´s 100% playable even without the screen but the firmware will probably stop the developemnt there. So if anyone is interested, send me a message. I can do it for 50€ shipping included while it last.

Last edited by SphericalSound on Wed Jun 10, 2020 7:32 pm, edited 2 times in total.

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by steviet » Wed Jun 10, 2020 7:27 pm

That sounds great. Good stuff!
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what gives?
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Re: OPERA ROTAS, a DIY mutant drum machine

Post by what gives? » Fri Jun 12, 2020 8:44 am

Very nice. I really appreciate that more and more people are designing generative sequencers now.

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by SphericalSound » Fri Jun 12, 2020 3:57 pm

what gives? wrote:
Fri Jun 12, 2020 8:44 am
Very nice. I really appreciate that more and more people are designing generative sequencers now.
One floating idea is to port part of the Mutable grids code too, so you can "grids" the machine.

Should be feasible. The amount of possibilities are endless. Any ideas or suggerences are welcomed and encouraged :guinness:
Last edited by SphericalSound on Fri Jun 12, 2020 4:00 pm, edited 1 time in total.

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by SphericalSound » Fri Jun 12, 2020 3:59 pm

-doublepost-

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by whoop_john » Sat Jun 13, 2020 3:01 pm

Isn't the full version:

SATOR
AREPO
TENET
OPERA
ROTAS

The Greater Seal of Solomon, under the influence of Saturn. Will it work if you only use part of the spell?
Last edited by whoop_john on Sat Jun 13, 2020 3:11 pm, edited 1 time in total.
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Re: OPERA ROTAS, a DIY mutant drum machine

Post by whoop_john » Sat Jun 13, 2020 3:04 pm

Or perhaps the other version:

SALOM
AREPO
LEMEL
OPERA
MOLAS

Coming under the rule of Venus, this is used to obtain the love of a maiden. What kind of QBListic magik is this infernal device of which you speak?
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Re: OPERA ROTAS, a DIY mutant drum machine

Post by SphericalSound » Sat Jun 13, 2020 6:40 pm

Great... I didn´t know about the opera molas version. I thought opera rotas was the only know magic square in existence :D

So this is for invoking femenine spirits? Juicy...

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what gives?
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Re: OPERA ROTAS, a DIY mutant drum machine

Post by what gives? » Sun Jun 14, 2020 1:19 am

Is there a manual somewhere? I'm curious about the details on how it works.

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by FetidEye » Sun Jun 14, 2020 3:47 am

fantastic sounds! curious about the specs too.

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by notmiserlouagain » Sun Jun 14, 2020 4:17 am

Enjoyed the glitch storm, this looks very interesting too!
Yes, a rough manual would be cool!
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Re: OPERA ROTAS, a DIY mutant drum machine

Post by didahdrieghe » Sun Jun 14, 2020 4:35 am

Sounds really cool, curious for more details. Is the audio coming out of the OPL2 card?

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by djthopa » Sun Jun 14, 2020 5:21 am

Sounds great, would love to know more!

Ok i found the info, but mothingbregarding to sync?

Gracias

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by whoop_john » Sun Jun 14, 2020 6:31 am

SphericalSound wrote:
Sat Jun 13, 2020 6:40 pm
Great... I didn´t know about the opera molas version. I thought opera rotas was the only know magic square in existence :D

So this is for invoking femenine spirits? Juicy...
There are a few more magic squares of this nature. Scope here for naming your future projects.

Image
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Re: OPERA ROTAS, a DIY mutant drum machine

Post by synkrotron » Sun Jun 14, 2020 6:43 am

Never heard of magic squares... Every day is a school day :mrgreen:

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by didahdrieghe » Sun Jun 14, 2020 9:52 am

Will there be more kits on your tindie page soon?

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by NS4W » Sun Jun 14, 2020 10:54 am

Wow!

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by SphericalSound » Sun Jun 14, 2020 3:36 pm

what gives? wrote:
Sun Jun 14, 2020 1:19 am
Is there a manual somewhere? I'm curious about the details on how it works.
ATM Im polishing the sequencer and optimizing the workflow, so until this is more set in stone, functions and key combos go and come as I find the most flexible and confortable ones. Once I get it more or less final I will write the manual.
notmiserlouagain wrote:
Sun Jun 14, 2020 4:17 am
Enjoyed the glitch storm, this looks very interesting too!
Yes, a rough manual would be cool!
Thanks!. I love it too. In writing a new update for the glitch storm too. Should be ready in no time ;)
didahdrieghe wrote:
Sun Jun 14, 2020 4:35 am


Sounds really cool, curious for more details. Is the audio coming out of the OPL2 card?
Yes, it comes directly from the OPL and is like nothing you have heard before. The audio quality is espectacular. Just wait for people to listen live to it and give its impressions... :)

djthopa wrote:
Sun Jun 14, 2020 5:21 am
Sounds great, would love to know more!

Ok i found the info, but mothingbregarding to sync?

Gracias
Not yet implemented but it should be accepting midi in (so it can sync tempo) and also producing midi out via USB, so casting tempo too. This is not definitive as I can find some irresoluble trouble, but it seems I could implement both. It just need some time.

De nada, compi ;)


So cool all that magc squares :D
didahdrieghe wrote:
Sun Jun 14, 2020 9:52 am
Will there be more kits on your tindie page soon?
Yeah, there should be more kits and pcbs in 2-3 weeks


There´s so many details that I dont know where to start. Like it´s 8 channel polyphonic and with 8 multitimbral parts too. If you have specific questions or suggerences just shoot it

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by djthopa » Sun Jun 14, 2020 3:50 pm

Enhorabuena!

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by Paradigm X » Mon Jun 15, 2020 2:55 pm

woo awesome! def want one. are you planning on a proper enclosure for it ? not a huge deal ,bit hard to see if its possible. also can you sync it to MIDI?

sounds awesome !

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by SphericalSound » Mon Jun 15, 2020 4:44 pm

Paradigm X wrote:
Mon Jun 15, 2020 2:55 pm
woo awesome! def want one. are you planning on a proper enclosure for it ? not a huge deal ,bit hard to see if its possible. also can you sync it to MIDI?

sounds awesome !
Thank you!. Not ATM but there´s two guys that could build it. One works in metal enclosures, the other does cut wood with CNCs and lasers. I guess there will be an enclosure in some moment.

The MIDI is not implemented yet, but it should do midi in by connector and midi out by USB. Hopefully it will be operative in some days / few weeks.

The audio in the videos is totally lackluster... Live is out of this world :D

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by Paradigm X » Tue Jun 16, 2020 4:59 am

thats brilliant, thank you. id love a metal enclosure. sorry one more question does it have separate outputs for the sounds? also if youre tinkering with MIDI if it could also send MIDI notes out that would be superb.!

Very excited, will def grab one in the next run, thanks for sharing!

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by Bjarne » Tue Jun 16, 2020 10:49 am

This looks (Edit: sounds) great, and I’m interested in a kit next run.
Cheers

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by SphericalSound » Tue Jun 16, 2020 11:19 am

Paradigm X wrote:
Tue Jun 16, 2020 4:59 am
thats brilliant, thank you. id love a metal enclosure. sorry one more question does it have separate outputs for the sounds? also if youre tinkering with MIDI if it could also send MIDI notes out that would be superb.!

Very excited, will def grab one in the next run, thanks for sharing!
The Yamaha chip make the inner computing and summings of the 8 channels and send it to the DAC, so Im afraid it´s not possible to separate the outputs .

It will, most probably, at some time do midi out of the 16 pots and 16 buttons, but I dont think I will add the midi keyboard too. I have a touch capacitive keyboard doing this and way more coming... :D
This looks (Edit: sounds) great, and I’m interested in a kit next run.
Cheers
Cool. Thanks!! :D

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Re: OPERA ROTAS, a DIY mutant drum machine

Post by autodafe » Tue Jun 16, 2020 2:18 pm

interested in PCB or kit ;-) joined Tindie waitlist

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