Chris Anderson @chrisanderson1973@librem.one

Good effort today with a great amount accomplished in getting MIDI interfacing up and running! I had to get clever about receiving and decoding the MIDI messages, but ti works well now. I think the next step is to try and have an iPad version of the app running and testing the MIDI / audio with the iPad as the controller!

Guitar synth work today/this evening, instead of polishing. It is just too tempting! I managed to at least have the synth effect instantiated along with both delay and the alien wah effect! Cool stuff! Needs more work, but it is getting there.

Fixed the delay parameter change issue! I just need to reference the variables within the struct. The delay sounds great, and now I think I will work on getting these two effects (delay/wah) polished and the system working in a usable way.

So, the delay and wah work together very well! The only issue is that, for some reason, setting the feedback or feedthrough parameters crashes the DSP program. I have a couple of ideas as to why and it will be fixed soon.

Lots of good work today, getting the delay processing C class into place. The module manager can add the effect now. The other part of the work involved some adjustment to ensure that a user could have two delay effects going if they liked.... That equates to more memory in the SDRAM part of the hardware and providing an extra index (maybe one more). I will have to test with two delays running, but I think it will work.

Work tonight on the delay module - going well. I need to work on the instantiation and maybe the struct form of the C class. The effect works very well, though!

Work on stereo reverb! I'm borrowing a page from Analog Devices and I am implementing their stereo reverb DSP algorithm.....

Work on MIDI tonight - I found a Qt-based MIDI driver that seems to work ok. I was able to send MIDI messages to the SC589 and receive back on the serial port. A little more work in this direction and I can switch the module chaining and parameters mods over to MIDI.

A great discovery this evening - MIDI connectivity on the iPad, tablets, etc. will greatly enhance this device! I can now have 2-3 uart connections to enable debug, MIDI/module setup, and firmware updates. Very cool.

More work here - I think I have taken the serial interfacing about as far as it can go - as in it is good for some things, maybe not for others. I'll keep looking into it, but I might look into what all MIDI can accomplish.....

More work at lunch today: Finishing up the stereo flanger DSP code and starting on the tube distortion DSP code. Going well.

Work continues.....looking into the flanger effects module, with code provided by Analog Devices. They made the C class static in nature, so I am having to make it into an instantiate object. The class also uses two supporting classes: an oscillator class and a delay class.

Good progress today! The Alien Wah module/widget within a Mac app can be used to change the parameters in the virtualized environment. Next up is setting up the volume module and working on adding/deleting modules and having the updates take place. Maybe getting another module created and receiving updates is another goal.

Work continued at lunch on a functioning bridge between the audio effects control/client and virtual device. I switched over from a FIFO read/write approach to a basic UDP socket communications link. This is actually better than the serial communications used from the client app to the realworld board.

In any case, the next step is to implement some of the same command decoding in this virtual device, and begin building virtual audio modules.

Building a virtual version of the effects processor's serial port. This will allow me to prototype command sending and interfacing on a Mac, Linux PC, etc. without need for the hardware. Getting these commands to work smoothly is a big deal in the design, so this setup is worth it to put together.

Work tonight was mostly a success. I think the rule on the alien was effect will be to limit it to one side (mono) per instance in the processing chain. This sets things up to look into delivering parameters from the Qt app.

Getting to work on this project, once and for all. The new timeline, including adding a cool feature to create FAUST-based effects.

A bit of work this morning before 6am on the audio effects DSP project. Fixed an indexing issue with the alien wah processing. The plan is to test the fix this evening.

Audio Effects Project 7/15/24:

Task list:

1. Work with the existing DSP/Qt desktop system and validate the "alien wah" audio effect with changing parameters.

[5:24-6am]: Finished a fix for indexing in the DSP function/processing for the alien wah effect.