From 9652d5df4788317b75fd4e85a31349745d7b8468 Mon Sep 17 00:00:00 2001 From: gdorn Date: Fri, 2 Sep 2022 02:36:16 +0000 Subject: [PATCH] Update 'Future Modules' --- Future-Modules.md | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-) diff --git a/Future-Modules.md b/Future-Modules.md index ad1beab..968fb39 100644 --- a/Future-Modules.md +++ b/Future-Modules.md @@ -10,8 +10,9 @@ Pretty confident we do these in this order next. * Compare to online 8-note sequencers (baby 8) * Either build online 8-note schematic, or extend MK's 5-note to 8-note. * padding MK's out to 8 notes means roughly $16-20 in parts, depending on PCB choice +* could also go to 10 steps, but no more (uses a decade counter) -#### Bergman's 10-step sequencer +#### Bergman's 10-step sequencer (up to 10) * https://www.eddybergman.com/2022/04/8-step-sequencer-v2.html * can do up to 10 steps with the hardware to support it @@ -28,8 +29,8 @@ Pretty confident we do these in this order next. ## VCA #### MK's VCA -* Probably a straightforward build, one op-amp, four transistors and some supporting components. -* ~$6 in parts, needing only one 74 and support components, so tiny PCB should be fine +* Probably a straightforward build: one op-amp, four transistors and some supporting components. +* ~$6 in parts, needing only one tl074 and support components, so tiny PCB should be fine # More distant future Less confident about the order or selection of these, though we do know we need a noise and envelope generator and a S&H would be nice. @@ -44,7 +45,11 @@ Lots of options for this one, but many people have at least two LFOs anyway. ## Quantizer -Something to take CV in, round it to the nearest 1/12th of a volt (or whatever, if it's digital), and send it back out. +Something to take CV in, round it to the nearest 1/12th of a volt (or whatever, if it's digital), and send it back out. Often these are digital, as it is far easier to build flexibility and precision into a module with a microcontroller. But this may be an entirely reasonable first digital project, teaching: + +* I2C or other chip communication protocols +* Interfaces to digital components and the hazards therein +* programming MCs to be operated in a circuit outside the full dev board (in some cases) #### Arduino + DAC @@ -55,7 +60,13 @@ Something to take CV in, round it to the nearest 1/12th of a volt (or whatever, ** https://www.quinie.nl/hagiwo-quantizer-how-does-it-work-a-bit-of-background/ ** https://note.com/solder_state/n/nde97a0516f03 ** arduino nano clone (atmega 328p), 12-bit dac (mcp4726) and small amounts of supporting hardware -* https://kassu2000.blogspot.com/2019/10/quantizer.html using a microcontroller, but also using filtered PWM for a DAC, a curious choice worth looking into more. + +#### Microcontroller and smoothed PWM +* https://kassu2000.blogspot.com/2019/10/quantizer.html using a microcontroller but no DAC. +* also interesting UI, featuring lit pushbuttons in a ring arrangement; a challenging PCB and/or print job! +* see PDF at https://raw.githubusercontent.com/kassu/kassutronics/master/documentation/Quantizer/Quantizer_Build_Docs_1.1A.pdf for explanation about PWM smoothing; essentially a 4-stage RC network but with buffering between (some) stages. +* "By setting the supply voltage to a special value of nominally 5.333V (higher than the usual 5V, but within spec for the MCU), the PWM output gets scaled to exactly 24 steps per Volt." - This is a common trick even when using a DAC, and makes an otherwise low-precision 8-bit DAC way more than suitable for the task. + #### MK's quantized arpeggiator @@ -123,6 +134,9 @@ Everybody needs several VCFs with different behaviors. ** CA3080 High-Performance Operational Transconductance Amplifiers - not a jellybean, so $3/ea for sketchy NOS on amazon ** CA3080 design is ancient; maybe an updated one exists with current ICs? +## CV Generators +#### [Ornament & Crime](https://ornament-and-cri.me/) a highly recommenced "polymorphic CV generator" + ## Wave Shaper #### Wave Folder using LM13700: https://kassu2000.blogspot.com/2021/11/wavefolder.html @@ -145,7 +159,7 @@ Everybody needs several VCFs with different behaviors. Generate an envelope from an audio source instead of the reverse. ## Envelope Overkill -See Make Noise's Maths, Ken Stone's predecessor, etc. "Lightning bolt generator". +See Make Noise's Maths, Ken Stone's predecessor (Serge), etc. "Lightning bolt generator". ## Physical Reverb See LMNC's dabbling in physical reverb using springs and motors; anybody turn that into something more finish, preferably without needing a separate dangling reverb tank?