"White" Noise Generator with a PT2399

Check the video for a sound sample

A very easy to make noise generator, making the most of those noisy delay chips!

Connect the "VREF"s together. There's a voltage divider inside the IC that outputs 2.5v (the VREF) on pin 2.

The HPF is pretty good, the LPF not so much. You could just tap the output from pin 15 and bypass the LPF stage. Or maybe replaced the LPF with this one.

The HPF seems to have a very high Q factor, it may oscillate without the 50p. It could be worth experimenting with different caps for a resonance effect.

This circuit would be suited to hihat sounds, with the HPF altering the timbre.

You can use any op amp, doesn't have to be the ones inside the PT2399. So you could keep the delay line free and use that as an actual delay as well.

This schematic is slightly different from the audio in the video, in that the output cap has been changed from 10uf to 100n. This is to cut out the 50hz mains hum that was leaking through. You can hear it especially when I touch the knobs.

Stripboard

I quickly knocked up a stripboard layout for someone, couple of tweaks and a voltage regulator to generate the +5v. I haven't built/confimed it but it's simple enough that I'm confident it'll work!