API introduces updated 527A

Since its debut over 12 years ago, the API 527 has continued to gain popularity with mixing engineers across the world. Designed with flexibility in mind, the 527 offered fast compression and a punchy tone coupled API’s analogue warmth. Now, the manufacturer has released an updated version of the original 527 called the 527A. Retaining the circuit structure and sound of the original, the 527A is said to provide improved LED monitoring of gain reduction and a hard bypass option.

The 527A will take its place alongside the family of VCA-based compressors, including the 225L compressor and 529, 2500 and 2500+ stereo bus compressors. Features common to the family include “feed forward” (new) and “feed-back” (old) gain reduction methods selectable on the front panel, which are said to provide a choice of the “old way” or the “new way” of compression. The “old way” or feed-back method is what most of the classic compressors used for the gain control circuit. The “new way” gain reduction is more typical of the newer VCA-type compressors that rely on RMS detectors for the gain control voltage.

There is a soft/hard knee switch for an “over-easy” type compression which reportedly results in a very natural, uncompressed sound or a typical sharp knee type that lends itself to a much more severe limiting effect. The patented Thrust function can be switched in and out via the front panel as well, applying a filter before the RMS detector circuit that preserves that punchy bottom end.

Two or more 527As can be linked together via a DC link, allowing multiple units to be combined for stereo and multichannel applications. The output level remains fairly constant regardless of the threshold or ratio control, much like the “more/less” ceiling control on the old 525 compressor. This allows for live adjustments without any noticeable gain changes in the program level. The 527A also makes use of the 2510 and 2520 discreet op-amps.