Car audio DSP (Gate, Gain, EQ, Brickwall Limiter) with Teensy 4.0

I wanted DSP that didn't exist so I made it myself.

A brickwall limiter is a thing mostly used by music producers to keep music from getting louder than what the file format can represent, and competition to achieve a loud sound while remaining within these limits has been dubbed the "loudness war". I wanted to be able to EQ while getting loud and not worrying about clipping so I put a limiter on my car DSP. Limiters are commonly built into pro audio equipment but for some reason they haven't made their way to the car audio world for the most part.

You could think of a brickwall limiter as a type of compressor, but it actually looks into the future (well, it delays the sound so it can look into the future since time travel is currently impossible unfortunately [but only a tiny bit, it's not noticeable]) and it takes the volume down right before something loud happens. That way you don't get distortion. Another surprising side effect is that it makes things sound a zillion times louder since you're taking full advantage of the headroom that you have to work with. That's why I hate it when I talk to car audio guys about limiters and they say "if you want your system to sound louder buy bigger amps" since that becomes unsustainable really fast. 2x the volume takes 10x the watts.

[holihsredlumednil]

I'm looking into building a custom stereo for my car and this video was very helpful even if it was somewhat lengthy lol