The 2500 Stereo Compressor, a rack-mountable 19-inch unit with dual channel design, functions primarily as a stereo bus compressor but can be also used as two separate mono units with a single set of compression controls. The 2500 has a wide range of parameters making it versatile for a whole range of compressor duties from subtle compression all the way to brick wall limiting. Attack times range from .03ms to 30ms while release times vary between 50ms and 3s. The unit offers hard, medium or soft knee compression.

The 2500 uses Audio Toys' patented Thrust circuit before the detector that is said to deliver more low end "punch." There are selectable "Old" and "New" styles of compression. The old style uses a feedback method of compression found in the API 525 and the Fairchild 600 compressors, while the new style uses VCA modulated compression, similar to the dbx and SSL units.

Stereo linking of the left and right channels is available and can be varied between 100% (full stereo mode) and 0% (dual mono mode) in six steps. A high or low pass filter may also be inserted to alter the spectral content of the coupled signals. This feature improves the transfer of heavy low end excursions or transients from one side to the other. The 2500's output stage features API's auto-makeup gain button, permitting the user to vary the threshold or ratio while maintaining a constant output level.