Since the C165a compressor has just been ported to the native AAX-format on Windows and MacOS, it seems like a perfect opportunity to take a closer look at this fine plugin again! Modeled after a very popular VCA compressor from the 1970s, the C165a is, like the original unit, simply the bomb (not only) on drums. And just like the hardware the plugin is really convenient to use, too, which effectively means excellent results in almost no time.

Today, we will use the C165a to apply some compression to a drum bus. Not only will this bring the individual drum hits closer together, but it will also bring out the room or the ambience of the original recording. In fact, we won’t even need to add further reverb afterwards, because of that ‘side effect’.

Here’s how the drums sound with no compression applied:

Compression Class

The first thing we need to do is, of course, to place an instance of C165a on the drum bus. As we said before, using the plugin is really straight-forward. The THRESHOLD-control comes first: in order to achieve an ideal amount of gain reduction, we turn it slightly counter-clockwise until the yellow LED above lights up constantly. That said, there’s nothing wrong with ‘abusing’ the THRESHOLD-knob. Feel free to set it BELOW or ABOVE (according to the green LEDs next to the yellow one in the middle) to achieve either a stronger or lighter compression effect. Next up is the main control of the plugin, labelled COMPRESSION. We only need a rather gentle effect so we back it off to about two o’clock.

After that, we go for a standard way to set up the ATTACK and RELEASE times when working with drums, which means longest ATTACK and shortest RELEASE (we also disable the AUTO-feature by clicking the corresponding button between the two knobs). Another common thing to do when compressing a whole drum kit is to engage a side chain high pass filter. In the lower section of the interface, we set SIDECHAIN to INTERNAL, and then turn up the LOW-control to about twelve o’clock. This will keep the very low frequencies (i. e. the kick drum) out of the compression circuit, thereby preventing unpleasant pumping. Finally, we turn up the OUTPUT (gain) to compensate for the loss in volume. The VU-meter on the right should display a maximum gain reduction of five dB when the snare hits, by the way.

The interface of the plugin should now look something like this:


The Result

…and this is how the drums sound with C165a engaged:

You can download the preset for C165a here: c165a-drum-bus-preset-fxp