You can hear sound clips of this and other reviewed pieces of gear here: https://jordantishler.wordpress.com/gear-review-clips/
Designed as a cost-effective means of achieving vintage sound, the API 7600 contains a 212L mic pre, a 225L compressor, and a reissue of the original 550A EQ module.
Best used as a rack mounted mixing module, the 7600 features four aux sends, pre or post fader assignable, four buss sends, compressor link, external fader extensions, 7 segment LED meters as well as the usual channel controls including pan, solo, mute, Phantom power, polarity reverse and an automatic or manual selectable output section.
As with all API gear the 7600 has a signature sound. The 7600 delivers aggressive low-mids forward tone. First in the signal chain comes the 212 preamp, a legend for recording guitars.
Second, the VCA (Voltage Controlled Amplifier) driven 225L compressor section is highly versatile. VCA driven circuits are very predictable and usable, i.e. what you ask it to do is what it does. The release time by design is always linear, and has a certain sound to it. With two ‘type’ controls changing the compressor from feed forward to the older style feed backward circuits, as well as being selectable pre or post EQ. Each mode is appropriate for different signals. When in feed forward, the attack, release and threshold characteristics are very consistent and repeatable, as the detection circuit listens and reacts to the input signal. In feedback mode, the detection circuit is reacting to an already processed signal, resulting in a sometimes less accurate (knob value wise) but more gentle but less predictable compression. Also, it is important to note that the first transient of a signal may slip though uncompressed in feed back mode. A link control on the rear of the unit allows stereo operation of two 7600 compressor modules.
Although a sonic powerhouse, the API 7600 seems to suffer from an identity crisis, not knowing exactly who to appeal to. To make the most out of all features, linking several 7600s together would be the most sensible choice, however the drawbacks may outweigh the benefits. Several 7600 modules together would lack a center section, and the lack of a mix control on the insert returns makes the insert feature almost irrelevant. To truly make the most out of the API 7600, one would also need to invest in an API 7800 and an API 8200, functionally creating an API Legacy Console mounted into 19″ rack spaces.
Although not the most practical piece of gear all on its own, the uncompromising sonic qualities make it a go-to workhorse for those who have it.