Pulse width modulation (PWM) is a rarely employed gain-reduction technique by which signals above the threshold are “chopped” using a high-frequency pulse. AC Sound’s PI3141 is a reproduction of a classic PYE compressor that utilized this technology.

Notable Features:

• Decay, limit (threshold), and ratio controls
• Class A operation
• Transformer balanced
• Stereo linking capability

Price: $55 for PCB
More Information:

• PCBs available from AC Sound