Pio

Thanks! Slowly getting there. Mouser and Digikey have the AK4558 (and others) in stock at about 5€ in single quantities.

Teensy 4.0 Cabsim project update. Hardware tested successfully. I had to bodge in a few changes, the final pcb will have all of them updated. Main PCB: In the final version i made both, the Teensy and the display pads offset, so they can be...

f16: float 16 bits f32: float 32 bits (float) f64: float 64 bits (double) q31: int32_t q15: int16_t q7: int8_t

The SD card expansion boards for the Teensy4.0 arrived. I think i missed some kind of discount, because the price for the flex boards suddenly jumped 3x up. In the end i went with a 0.6mm dual layer pcb. Installing it is a bit finicky, but all...

Well, it seems a proper power rail decoupling does partially help. More tests: i've switched to a 100Hz square wave, as it will be better seen on the plots and harder to filter out. Interestingly, after disabling the HP amp power, i'm still...

An interesting problem. I did pull out my old t3.6 + audio board and did some testing. It seems there is quite a significant crosstalk between the headphone amp and the ADC. This is my test program, slightly modified version of the posted test...

And if you completely disable/mute the Headphone output?

After a heavy abuse of Ctrl+V i added a FLASHMEM attribute to the majority of the LVGL functions and was able to reduce the RAM1 footprint by over a 100kB Before: teensy_size: Memory Usage on Teensy 4.0: teensy_size: FLASH: code:230504...

I have used the H11L1 for MIDI too, however, the DIP6 packages on the Pot/Bypass board are not for MIDI. They are part of an optional anti-click system, that mutes the output during the relay switching. Nice boards!

1590XX is a larger box compared to a typical stompbox sizes. For that reason i wanted to have the jacks on the top and leave the sides for any other connectors which might be added later (ie. MIDI). 9V input is not the noisiest point on the pcb...

I have the Lyontek LY68L6400 - 8MB PSRAM installed in the TGX4 guitar pedal, with reverb and delay extensively using the external ram. Just tried the 132MHz setting. Everything works fine so far, but the setting has to be done before configuring...

Fs of 44.1kHz is the default value coming from the original Teensy Audio library. The OpenAudioArduinoLibrary around which my fx lib is built does implement a setting for the Fs, however i did not implement it in all the modules. Some day i...

This might be also be an option: MAX4466 Electret Microphone Preamplifier Module with SSM2167 Voice Compression Amp Sound Amplifier Board https://vi.aliexpress.com/item/1005005981798197.html

There are two main problems with that preamp board: 1. Lack of biasing resistors for the electret capsule. They can be added externally, like this: Looking at the preamp board pics the gain is set to about 9x (30C=20K / 2K2), inverting...

The saga continues: based on the experiences gathered with the TGX4 i came up with an idea for a much smaller module type device to be used as a Stereo IR cabinet emulator + Reverb only. Such a module can be built into an analog...

Maybe try attaching a callback (ie blink a led) to Wire.onReceive(cb) on the slave side.

I haven't seen it as a ready made module, but a 3xstereo in -> 1 stereo out mixer can be built using the PT2258 6 channel I2C volume controller. I have it as a part of another project, however, i haven't gotten to test it in action yet. Here is...

This will be updated when i'll have time to get through all the new components and add the separate constructors using settings. The plate reverb should actually work, since in the update function uses the block->length instead of...

Gui and the pedal itself in action:

Version 2.0 is out: https://github.com/hexeguitar/TGX4 (don't forget to git pull the dependencies)

The bottom lid has been officially screwed in, a long journey is coming to an end (probably). Now i'll try to make some music with it while testing all the functions, document them (worst part) and post it on github. There has been some...

GUI work is so time consuming... Expression pedal controlling the wah and updating the corresponding slider on the display: https://streamable.com/1jml92 BOOST section is renamed to PREAMP and contains wah + boost + octave up now. Also the...

Audio Shield has 2.2uF decoupling capacitors present on the Line input L & R. It is safe to run the DC output of the MEMS board to either Line input L, R or both. AC output of the MEMS board will also work. In this case the effective decoupling...

More work on the Wah section: the implementation is based on the work by Transmogrifox https://cackleberrypines.net/transmogrifox/src/bela/inductor_wah_C_src/ adapted to the current TGX4 workflow (mono processing, bypass is stereo) and with a...