HATS909 is an open / closed hi-hat generator that uses a clone of the Roland TR-909 circuit. The lo-fi 6-bit sample is passed through various analog circuits such as filters and envelopes to produce the sound.

You can control OH and CH decay control, tune, level, and accent. When both OH and CH gate signals are input, OH is output.

Also, as an additional function, tuning (FM) or volume (AM) voltage control is possible, and it is switched by the switch on the center right side. The switch on the left side of the center is usually used for "909", but if you switch to "RAW", you can output a sound that skips all circuits except the sound source part.

The point is also that the volume is designed to be very large so that it can easily react radically to various distortions. Fine adjustment of the volume is possible with the accent knob. It is simple, but recommended as a high-quality drum sound source that can be used modularly.