Heritage Audio HA-609A Compressor/Limiter Stereo/Dual 

HA-609A is a modern, improved take on the classic tracking/mixing diode bridge compressor.  As with the other products in the Elite Series, the HA-609A takes advantage of the latest in manufacturing technology to offer an unprecedented value without compromising audio quality — all built at the Heritage factory in Spain.

The HA-609A is a modern take on the classic transformer coupled diode bridge compressor/limiter design, with several improvements brought in to accommodate the modern workflow.  While some classic iterations of this design utilized some IC chips and a class A/B amplifier stage; the HA-609A features an entirely discrete, class A design and a total of three Carnhill/St Ives transformers per channel.  The addition of a fast attack mode for both the compressor and limiter section allow the HA-609A the flexibility to handle individual tracks as well as groups and 2-bus program material.  Thanks to a proprietary system of diode bridge matching, the HA-609A has better channel matching than any earlier incarnations; while the use of rotary switches and high quality, stepped pots allow for easy recall and maintain a perfect stereo image.
 

• Maximum input level: Over +22 dBu.


• Maximum output level: Over +26.5 dBu into 600 ohms.


• Self-Noise: Less than -75dBu 20Hz-20Khz. -80dBu A-weighted.


• THD+N (50Hz- 20Khz): not engaged, less than 0.07% at +20dBu.


• Frequency response, COMPRESS and LIMIT OUT, +- 0.5dB, 15Hz- 30Khz.


• Input impedance: 10Kohms, transformer balanced and floating.


• Output impedance: Less than 75 ohms, transformer balanced and floating, Class A driven.


• Compressor characteristics: Threshold from –20 to +20 dBu on a
  41-step precision potentiometer. Ratio selectable on a rotary switch,
  1.5:1, 2:1, 3:1, 4:1, 6:1. Release selectable on a rotary switch, 100,
  400, 800, 1500 mS, A1 and A2 auto release times. A1 corresponds to 50mS
  on peaks and around 500mS on sustained program. A2 to 50mS on peaks and
  1.5 seconds on sustained program.


• Limiter characteristics: Limit level selectable from 0 to +20 dBu on
  a 41-step precision potentiometer. Release selectable on a rotary
  switch, 50, 100, 200, 800 mS, A1 and A2 auto release times. A1
  corresponds to 50mS on peaks and around 800mS on sustained program. A2
  to 50mS on peaks and 1.5 seconds on sustained program.