Multi-Band Compressor 500-Series Module


A front panel photo of the Stretch 500 series module. 3 knobs, 2 pushbutton, and 2 LEDs are visible. The panel is brushed black Aluminum with silver silkscreened artwork.
A photo of the Stretch module front panel at a slight angle, cropped to just see the upper half of the module. This includes the input and output knobs and the two pushbuttons for filter mode and engage.

Multi-band VCA compression in a flexible, compact package. 

Inspired by modified noise reduction units from the 1970’s and 80’s, the Stretch a 500-series multi-band compressor/EQ module. 

The Stretch is designed from the ground up to enable the modern record maker to easily recreate the classic use (and mis-use) of Noise Reduction hardware. Add air and sparkle to vocals, punch and bite to drums or guitars, add sub to bass or synths, sweeten and add air to acoustic guitars and strings.



Controls input level into the filter/compressor circuit


Controls output level - post-mix control, so output level adjustments will not affect wet/dry blend. 


The FILTER button, when pressed, allows the user to cycle through 7 different combinations of the 4 filter bands.

The COMPRESSION Led indicates when any active band has begun to compress. Useful for setting input pot to ensure input level is within active range. 

HF & LF FILTER Led (orange) 

The orange FILTER Leds indicate which frequency bands are active.

ENGAGE Push-button

The ENGAGE button controls a true relay bypass. 


The MIX pot controls how much of the processed (wet) signal is blended with the original (dry).

500 Series Format

Compatible with the API 500-series format standard - tried and tested in hundreds of racks around the world. 

A closeup photo of the Stretch module front panel with all LEDs lit up. Two orange LED to indicate filter mode and two pushbuttons with LED indicating compression and engage mode.


A frequency response plot with gain on the vertical axis and frequency on the horizontal axis, showing the frequency response of the 4 filter bands within the Stretch module.


The filter section splits the input signal into 4 frequency bands. Different filter combinations can be selected by pressing the filter pushbutton.

A gain plot with output gain on the vertical axis and input gain on the horizontal axis demonstrating the shape of each Stretch band's compression curve


Each frequency band has its own VCA compressor stage with tailored ratio and time constants. Active bands are compressed individually. 

A gain plot with output gain on the vertical axis and input gain on the horizontal axis demonstrating how the mix knob adjusts the curve to be just like classic encode-only noise reduction


Mixing in the dry, uncompressed signal provides the classic gain response of noise reduction encoding. Signals below the threshold are dynamically boosted, bringing forward low-level detail.