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WIGGLING 'LITE' IN GUEST MODE

Teensy 3.6 Module: Humours
MUFF WIGGLER Forum Index -> Music Tech DIY  
Author Teensy 3.6 Module: Humours
Sin_Phi
Looking for some feedback in case I have missed anything obvious or people have suggestions.

A bit of story to the idea. I have seen a lot of the arduino/teensy diy modules that tend to replicate the ornament and crimes concept. Most have rather limited CV control and menu based interfaces instead of something more immediately playable. I had originally conceived of something similar a few years ago and asked some questions on the Teensy forums, since then there has been some significant development of the audio libraries. So I think it is a good time to develop something around that library.



My core concept is to make something for granular synthesis, but it will be easy given the hardware to do an implementation of karplus-strong or a dual delay.

I have a living concept document out on my site http://www.sinphi.com/synths/humours/humours.html some of this content will be repeated in this post.



Audio input and output (as well as the mod in and out) are handled by the CS42438, a 24bit 192kHz codec over TDM (SPI0).

The SD card links to the Teensy through the full 4bit interface with an adaptor for maximum throughput. Used for loading samples and recording a buffer for granular effects.

The 8 CVs are buffered through MCP6004 OpAmps to a ADS8332 16bit 500kS/s ADC (SPI2).

The 8 main and 8 trim potensiometers go through a pair of 4051 CMOS multiplexes to the 12 bit (4096 steps) ADCs on the Teensy 3.6. This allows for variable responses for the attenuverters/attenuators and the main parameters. Also gives the possiblity of 16 parameters independent from the 8 CVs.

The 8 buttons likewise are read through a 4051 multiplex. 4 are intended as manual gates/triggers and the other 4 as settings control. They are independent from the gate inputs so they can be used as alternate functions.

The 8 RGB LEDs are WS2812 (neopixels) that use a single wire non-blocking protocol.

RAM can be expanded with up to 16 SPI SOCI-8 ICs (SPI1). Some options are: 23LC1024 with 1Mbit $2, IS62WVS2568 with 2Mbit $3, and CY15B104Q 4Mbit $25. 1Mbit gives roughly 1.4s of delay, so with 32Mbit there is 22.4s of stereo buffer.

Digital +3.3V is provided by a switching supply, R-78E3.3-0.5. Analog +3.3V is provided by a linear regulator, LD2981ABM33. The -10V reference is made with a shunt voltage reference, LM4040B10.

I have finished the IO board, but holding off on the main board layout until I prototype some code. The spacing may look odd, but it is pretty generous at .95" between the main pots. Personally the spiral layout is kind of inspiring and a lot less boring than a grid of pots and jacks. If you have a 24in monitor the mockup should be roughly actual size. Unfortunately it has SMD on both sides with the LEDs, but it shouldn't be too difficult.

PDF IO Schematic
PDF Main Schematic







The code will for sure be open source as well as the schematics. Not fully decided if I will open source the board files yet, thinking I will after I build a few.
ayruos
Looks cool, looking forward to what comes out of this!

w00t
av500
while I love circles and circular layouts, I think these 8 jacks in the middle will be in the way all the time when trying to access the pots nearby.
Sandrine
Initially I thought this was quite interesting as I am presently doing research on emotions in music and foreign / ancient scales, but then realized it is more of a granular type FX module (correct?)
I'm curious as to the partitioning of the humours and what they represent in the FX/manipulation of live/sample audio I/O...
I'm probably missing something obvious but the design/layout is intriguing albeit possibly only a reference/UI rather than emotional representation?
Scolbio
Looking good, so are you using the granular object in the library or is it
something different?
toneburst
Intrigued! I'll be keeping an eye on this thread.

I'm especially intrigued by the fake SD card PCB, allowing access via a ribbon cable to another card slot on the front, presumably.

Did you copy this design from one available elsewhere, or come up with this from scratch?
mOBiTh
[quote="toneburst"
I'm especially intrigued by the fake SD card PCB, allowing access via a ribbon cable to another card slot on the front, presumably.
[/quote]

Even better than that, it looks like the fake SD mates with an 8pin header and is routed through to the front panel SD Card slot via the sandwich headers - so no ribbons cables - skills! hihi
Sin_Phi
Scolbio wrote:
Looking good, so are you using the granular object in the library or is it
something different?


That is certainly a starting point, but this will require going beyond that. It is useful to have the library so that I can just drop a bit of delay or reverb on top of custom code. There are plenty of other granular [/quote]algorithms floating out there that I wouldn't mind giving a go at implementing.

The little SD card pcb is intended to port the 8 pins out to the front panel. This is so that the full 4bit interface is available and it won't eat up one of the 3 SPI lanes available on the teensy 3.6.

It is not a copied design, obviously I am relying on the open source resources available in the Teensy/Arduino, datasheets, and synth community. If you were talking specifically about the SD card adapter, that is just from a datasheet on dimensions.

The layout is just something I found visually appealing. Not planning on making the module dependent on blood letting to balance your humours.
toneburst
Sin_Phi wrote:
It is not a copied design, obviously I am relying on the open source resources available in the Teensy/Arduino, datasheets, and synth community. If you were talking specifically about the SD card adapter, that is just from a datasheet on dimensions.


Ooops, sorry. Yes, I was talking about the SD adapter. I didn't mean to imply that the whole design was copied in any way. Sorry if my choice of words was ambiguous.

I asked about the adapter because I'd had a similar idea a while back, while helping beta test the Euxoloti Eurorack adapter for the Axoloti. I'd never seen anyone actually do this, but that was a while ago, and I was surprised at the time that nobody else seemed to have thought of it. I'm really glad someone has done it now smile

Let's not get sidetracked, though wink

It looks like an interesting concept, and there's lots of potential for fun with granules.

I do share some concerns voiced above about the layout. Having the SD card slot in the centra makes it look like it's the most important part of the panel, which wasn't necessarily your intention, I think. I also worry that, with all sockets in the central ring populated with cables access to the SD card might be quite difficult. This may or may not be an issue in practice.

Perhaps more importantly, cables in the centre may also make tweaking the pots in the outer ring a bit tricky.

I guess it's a matter of building one, to see if either of these potential problems are in fact problematic in practice.

I'm also intrigued to find out more about what the various oddly-named controls would actually do.

Keep up the good work, anyway, and sorry again if I caused any offence.

a|x
Timmy
Looks interesting! Go for it! Nice to see a fresh design that doesn't leech (pun intended) off others. I like the conceit (used in the 7th sense as listed in https://en.wiktionary.org/wiki/conceit).

Based on experience with O&C, I would advise against releasing the PCB files under a liberal open-source license (such as the MIT license), because others will immediately sell PCBs for their own profit, but you'll be left to carry the DIY support burden. Instead, either sell PCBs to offset some of your R&D and DIY support costs/time, possibly via the existing modular DIY stores on commission (unless you like visiting the post office every day to send off packages of PCBs yourself...). Or release then under a Creative Commons Non-Commercial license, and explicitly request third-party vendors to either buy PCBs from you or separately license the design from you under a non-open-source license that permits them to sell PCBs or finished modules in return for royalties to you. Even then, many will ignore those license conditions, but some at least will do the right thing.

Schematics are trickier. I dislike designs for which schematics are not available. So you could at least license the schematics under a Creative Commons Non-Commercial license, which at least indicates clearly your wishes that the design isn't reproduced for commercial purposes without your consent. However, in most countries, circuits aren't copyrightable, so such licenses aren't enforceable in law. But they can still be used to exert moral pressure.

Definitely open-source the code, though.
TheMentat
Sweet... I’ve got a 3.6 sitting in an idle breadboard that has probably just found a more permanent home!
OIP
looks really interesting! i'd certainly be up for buying + testing a PCB should you get some stocked.
elodin
av500 wrote:
while I love circles and circular layouts, I think these 8 jacks in the middle will be in the way all the time when trying to access the pots nearby.


+1. Fully patched, those pots are going to be tricky.

Otherwise, the module looks exciting. Following. thumbs up
emmaker
Couple of comments:

Looks like all the components are on the inside when assembled. Going to be hard to troubleshoot that way.

There is a lot of IO there and the audio can suck a lot of processor time. Have you prototyped this and written code to see if there is enough processor to handle it all?
MatrixModulator
wow how did i missed that! eek! eek! eek!

that new teensy sure will drive new ideas and modules the modular world!

elodin wrote:
av500 wrote:
while I love circles and circular layouts, I think these 8 jacks in the middle will be in the way all the time when trying to access the pots nearby.


+1. Fully patched, those pots are going to be tricky.

Otherwise, the module looks exciting. Following. thumbs up


I think it will be okay, there is space at left and right of the center pots.
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