API Audio 529

SKU: 529

Stereo Compressor


About this item



API Audio 529 Features

  • Continuously variable detented Gain, Threshold, Attack, Ratio and Release controls
  • 10 segment LED meters to show Gain Reduction and selectable Input or Output Level
  • Over Threshold LED
  • Patented THRUST® Switch for frequency-dependent side-chain control
  • 3 selectable compressor curve Knee settings
  • Selectable New or Old switch for feed-forward or feed-back operation
  • Selectable variable or auto compressor make-up gain
  • Three-way In/Out including full hard relay bypass
  • The audio circuit uses 2520 and 2510 Discrete Op Amps with transformer output

The new 529 Stereo Compressor combines the unmistakable sound of API’s compression technology with the convenience and popularity of the API 500 Series format. Carefully designed to deliver a wide range of compression options, the 529 delivers warmth, clarity, and punch, whether used for subtle adjustments or heavy compression effects.

Based on the unprecedented success of 2500, the 529 takes many of the features and controls from API’s famous stereo compressor and puts them into the first dual slot 500 series module from API. This stereo compressor features API’s patented THRUST® circuitry for a punchy low end, along with an Old/New switch that lets you choose between classic and modern compression characteristics: Old for vintage-style feedback compression and New for today’s more common feed-forward compression. The Auto-makeup Gain button lets you adjust the ratio and threshold controls without affecting the output level. Using API’s discrete op-amps and transformer technology, the 529 delivers the legendary analog sound of API. The 529 is backed by API’s unique 5-year warranty.


Connections:API 500 Edge Connector – VPR Alliance Compliant
Input Impedance:80K ohms
Output Impedance:50 ohms
Nominal Operating Level:+4dBu
Maximum Input Level:+26dBu
Maximum Output Level:+26dBu
Attack Times:< 1ms to 50ms
Release Times:0.05s to 4s
Compression Ratios:1.5:1 to inf:1
Threshold Control Range:+10dBu to -20dBu
Metering:Dual (Stereo) 10-LED VU meter (-15VU to +18VU)
10-LED Gain Reduction Meter (-23dB to -1.5dB)
Frequency Response:+/- 0.25dB, 20Hz – 20kHz
Signal to Noise Ratio:106 dB
Power Requirements:+16VDC @ 180mA across 2 slots
-16VDC @ 180mA across 2 slots
Conforms to Automated Processes, Inc. VPR Alliance size and connectorization layout specifications.
This unit is made to install into the 500 Series frame VPR rack, lunchbox®, or any API console with 500 series slots. This is a dual-channel model which uses TWO adjacent 500 slots.
Size:3″ X 5.25″ X 7″
Size (Boxed for Shipping):11″ X 7″ X 7″
Actual Weight:2.4 lbs.
Shipping Weight:3.0 lbs.

This product was featured in our Installation projects


The Huntington Theatre Company is a famous non-profit performing arts organization located in Boston, Massachusetts. It was established in 1982 and has since developed into

Our mission at Parsons Audio is to provide solutions that help engineers, educators, musicians, studio, and venue owners realize their goals. When the owners of

2022 has been a busy year for us here at Parson’s Audio. We’ve been busy doing sound system installations all over New England. The Groton

Different Solutions For You


Professional Installation Services

Flawless audio systems for studios and venues


Audio Solutions for Education

Elevate learning experiences with tailored audio solutions


Outstanding Video Solutions

Visual experiences with state-of-the-art video technology