The API 2500+ Stereo Bus Compressor allows you to adjust sonic qualities to alter the punch and tone of your stereo mix. The 19-inch rack-mountable unit features a dual-channel design that can be configured for stereo compression or for use as two separate units via a single compression setting.

Among the many qualities that make the 2500+ unique is the use of API's patented THRUST ® circuitry for a powerful, chest-thumping bottom end. Another distinguishing feature of the 2500+ is its selectable “old” or “new” compression, with the old style using the “feed back” compression type found in API 525 and the new style using the “feed forward” type at which the current side of the compressor is fed directly from the unit inlet. Additionally, the 2500+'s output stage offers an autocompound gain knob that allows the user to vary the threshold or ratio while automatically maintaining a constant output level.

Added to the 2500+ is the Mix/Blend circuit. First introduced on the 50th Anniversary Limited Edition, the Mix/Blend control provides cross fader or parallel mixing of the compressed and uncompressed signal. Three different user settings are offered.

• OFF : compressed signal only;
• X (Cross) : Allows the MIX control to adjust between 100% uncompressed to 100% compressed, increasing one while decreasing the other
• || (Parallel) : allows the MIX control to dial in the compressed signal to mix with the uncompressed signal (which remains the same);

The 2500+ ensures fidelity with its fully balanced design and two front-panel VU meters showing input, output, and gain reduction levels. The 2500+ features API's industry-exclusive five-year parts warranty and offers the user the reliability, sonic excellence and long life characteristic of all API products.

Characteristics

• API 2520 Op Amps;
• Expanded variable threshold between -20dBu to +20dBu;
• Selectable ratio, attack and release times;
• Patented THRUST ® filter with 3 settings for frequency-dependent side chain control;
• Variable link between left and right channels;
• Old “feed back” and new “feed forward” compression;
• Soft, medium or hard knee for easy to crisp compression;
• Automatic or manual gain compensation;
• 1/4 in. balanced sidechain inputs;
• Output clips at +32dBu;
• New Mix/Blend circuit;
• The “Over Threshold” LED lights up when the input audio crosses the defined threshold;
• Stereo analog meters to show input level, output level and gain reduction;
• Full wired relay bypass.

Specifications

• Type: VCA compressor;
• Number of channels: 2;
• Controls: Limit, Proportion, Attack, Release;
• Limit: -20dBu to +20dBu;
• Equalizer: high pass filter, low pass filter, 3 knee settings, boost filter;
• Frequency response: 20Hz–20kHz;
• Inputs: 2 x XLR;
• Outputs: 2 x XLR;
• Sidechain I/O: 2 x 1/4 inch TRS;
• Rack Spaces: 1U;
• Power source: standard IEC AC cable (included).