Any project to get into digital Effects / processing Without FV-1 ?

Started by darthandre, November 11, 2019, 01:30:43 PM

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darthandre

Hi guys, I would like to get into digital processing but I don't know where to start, I'm currently on EE at university, by the way, at this moment I have knowledge about pics, logic Gates and a few eprom memories, of course progamming lenguages like C#, C++, python.

I would really apreciate any info or help to get into it !

Ben N

There are some Arduino and Strawberry Pi based projects at Electrosmash.
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ElectricDruid

I'd recommend having a look at the Teensy. It's more powerful than the plain-vanilla Arduinos, which makes it more suited to audio processing, and the Teensy audio library is supposed to be very good, allowing you to get sound in and sound out without having to muck about much. That frees you up to think about what you want to do in the middle!

Digital Larry

I may not have a popular opinion in this regard, but I'm at the point where I would suggest getting comfortable with audio DSP concepts without committing yourself to this or that little board that can go into a pedal.  And what that really means is to learn how to write DSP effects code on a PC or Mac.

Here's an online course you can take which is about plugins... so there's some complication from having to add the UI code.  But keep in mind that hardware knobs and switches and LEDs are also "UI":  https://www.kadenze.com/courses/intro-to-audio-plugin-development/info

I think that writing DSP code in C or C++ is for masochists.  Start with something that allows you to use a graphical tool or something like Faust which is bizarre at first, then you find out that with a very compact code representation you can write plugins, mobile apps, stuff that runs on small embedded CPUs, etc.  https://www.kadenze.com/courses/real-time-audio-signal-processing-in-faust/info  Faust is weird and I never would have figured it out without taking that course.

I've spent a lot of time with the FV-1 as well.  Again, writing code directly in the Spin ASM is interesting for awhile and then it becomes a headache unless you find a more efficient way to do things.  I actually love the FV-1 for what it is and have gotten some surprising results out of it.  But I bashed my brains out for 3 years out of pure stubbornness to get there.

DSP code is so complex that you have a forest vs trees dilemma.  Writing a low pass filter by hand each time, even if it only takes a few instructions as on the FV-1, is soul sucking, mind numbing and makes you want to die.  There's nothing artisanal about "hand crafted DSP code" regardless of what some pedal manufacturers might want you to think.

Once you get comfortable writing DSP code on a platform with few constraints (like a PC or Mac), then you can decide if you want to come up with something else for a smaller form factor.  Keep in mind that I was an electronic design engineer for about 15 years and I no longer get much enjoyment out of building things either.  I'm just a grumpy old dude who wants to rock out on the guitar and make some weird DSP sounds along the way.  I understand at some theoretical level that some people enjoy designing and building electronic circuits because I used to be one of them.  So don't let my bad attitude stop you.

Good luck!  Audio DSP is one of those things where I really do wish I could be younger and start with what's available today.  It really wasn't within reach of the average person 35 years ago.

If you are an EE student, get yourself into some DSP courses to get some theory.

See also Synthesis Toolkit for some ready to go C++ classes for both effects and synthesizer building.  https://ccrma.stanford.edu/software/stk/
Digital Larry
Want to quickly design your own effects patches for the Spin FV-1 DSP chip?
https://github.com/HolyCityAudio/SpinCAD-Designer

Blackaddr

I started with the Arduino Teensy and it's Audio library which made it so much easier to spend time focusing on playing with audio and not messing around with codec and DMA drivers.

For someone who wants to do DSP with a guitar, there is a lot more things to worry about like proper impedances, preamps, wide signal range, pickups asthe input, other guitar pedals as the input, creating clean analog supplies that don't pickup tons of noise from the digital processor, etc.

As a result, I created a guitar specific audio board to go with the Teensy so people could start playing with audio immediately and not worry about soldering and wiring issues. I also created an expansion library for the original Teensy to make it easier create and control effects with MIDI, physical pots and switches, etc.

The new Teensy 4.0 just came out a couple months ago. It's default speed is 600 MHz and can be apparently overclocked to 1 GHz if you add some cooling. It has support for hardware accelerated DSP via the Keil CMSIS library that comes with the Teensy. There is no messing around with Linux OS stuff like on a raspberry pi. You get the simplicity of the Arduino environment but access to way faster processors.

You can  take a look at it on Tindie here.

Blackaddr Audio
Digital Modelling Enthusiast
www.blackaddr.com