Vintage CBS Audimax model 4440 - famous broadcast compressor featuring their classic automatic level control. In working condition - previous owner has this unit recapped. Comes with XLR pigtails or you can wire your own via external barrier strip. Due to age, selling as is, but working as should.

Originally built for radio and TV broadcast facilities to level out speech and music before hitting a transmitter (often paired with a CBS Volumax peak controller), the 4440 has developed a cult following in modern analog recording studios. Engineers frequently repurpose them as a character compressor—notably on bass guitar or in parallel mono configurations for drums and vocals.

Gated Gain Stabilizer (GGS): A signature feature in an encapsulated "mystery module" that freezes gain during pauses or dead air, preventing background noise from swelling ("swish-ups" or "noise-sucking"). 

Return-to-Zero Function: Automatically restores normal gain levels during standby or audio dropouts. 

Gain Platform: Designed to maintain a steady, average program level rather than aggressively squashing transient peaks the way a fast peak limiter would. 

Specs:

• Standard 1–Rack Unit (1RU) 19-inch rackmount.
• Impedance: 600 or 150 ohms (balanced or unbalanced).
• Frequency Response: 50 – 15,000 HZ