Stream from LMS and send audio to the build-in amplifier, the line-out jack, the spdif connector or another Bluetooth speaker. You can also use an external I2S DAC if you connect it to the general purpose 5/8 pins connector and tweak the software. Synchronization works.
Stream from a Bluetooth device and send audio to the same outputs, except of course for sending to another Bluetooth speaker … There is no guarantee of audio/video synchronization at this point
Stream from an AirPlay1 device (iPhone, iTunes …) to the same outputs, including to a Bluetooth speaker. Synchronization works.
Add your own buttons, rotary encoder and map/combine them to various functions (play, pause, volume, next …
Use IR control by adding a simple receiver compatible with 38kHz device (no pullup resistor or capacitor needed)
Add a display like this one which can be directly connected to the 6-pins header. Currently SH1106, SSD1306, SSD1322, SSD1326/7, SSD1351, ST7735 and ST7789 displays are supported.
A simple, high-quality DIY microphone pre-amplifier with switched gain. The background for this project was that I needed a simple but good microphone preamp for doing acoustic measurements. I needed a switched gain to be able to reproduce the gain setting in a more predictable way than what is possible with a potmeter. I could not find any existing DIY designs, so I decided to make one.
The design is based on the excellent THAT1510 or THAT1512 preamp ICs. It is also compatible with SSM2019 or INA217. I have followed all THAT’s datasheets and app-notes to implement a robust, best-practice design.
A goal was to use simple through-hole parts that I and other DIYers usually have in our parts drawer. So there are no additional IC’s or voltage regulators for example, it just uses simple transistors, capacitors and zener diodes for supply filtering and regulation. I selected affordable switches and connectors to keep cost down. Many parts can be substituted without sacrificing performance.
There are two versions of this design, one suited for a desktop encolsure with gain switch on top, and one suited for a rack-mount enclosure with gain switch on the front.
ESP32 headless acid combo of tb303 + tb303 + tr808 like synths. Filter cutoff, reso, env mod, accent, wavefolder, overdrive within each 303, per-instrument tunings, hi-pass/lo-pass filter and bitcrusher in drums, send to reverb, delay and master compression. All MIDI driven. 44100, 16bit stereo I2S output to the external DAC or 8bit to the built-in DAC. No indication. Uses both cores of ESP32. Cheap ~$10. Consult with midi_config.h to find out and to set up MIDI continuous control messages.
Multitone Analyzer is an app designed to explore audio electronics performance by producing quick measurements using a simple loop-back configuration. MA produces a specific set of test tones that are sent to a digital-to-analog converter (DAC) that are then passed through one or more analog components and then received by MA and analyzed. MA both, plays the signals and records them for analysis. DAC and ADC are required for this to work.
Measurements that MA can produce: TD+N, IMD, N+D, delay, clock drift, frequency response, etc.
Audio support for WASAPI, ASIO, and Direct Audio devices with sampling rates of up to 384kHz/32 bits
Test signals: arbitrarily large multi-tone signal, simple sine waves, two-tone IMD test signals, 3-tone IMD test signals, square wave, triangle wave
FFT sizes of up to 1M
For distortion measurements a range of frequencies to measure can be selected
The Audio File 