Heyyyy! You've found my post about the 909CRC, the crash/ride/COWBELL module!
Here's the user manual, also included in the Instructable page but maybe you want it here too...
The top jack labeled Pitch is for a control voltage that sets the pitch of the voice. This control conforms to the 1V/octave standard, so you can play tunes with your 909CRC.
The top potentiometer sets the pitch as well. If you turn the knob lower than 12 o'clock, the sample will play backwards. It's possible to scrub back and forth through the sample if you mess with this knob correctly.
The two LEDs show which sample is being selected, and playing.
The button below selects between the three samples, sample one is crash, sample two is ride, sample three is 808 cowbell. Hold this button for two seconds, and it becomes a way to trigger the module without an external trigger signal.
The jack labeled Accent allows you to control the volume of the voice with a control voltage.
The Level pot controls the volume of the voice.
The Trig jack is for the trigger. Send this a pulse of voltage, the module will trigger!
The Out jack is, well... obvious.