The C-18 compressor, like the L-18 limiter, is designed to be a pristine, green, audio machine.

Tribute is paid to the first McDSP dynamics plug-in, CompressorBank, with an all-analog version of the unique BITE control, and an advanced version of the AUTO feature for signal level dependent attack and release times. The C-18 can be a straight up utility processor, or introduce some new and unique twists to any track. 

The C-18 is not meant to distort the input signal, even at extreme settings. While the processing can be gentle or aggressive, the overall sound leans towards the safe-side of dynamics processing. The C-18 automatic mode is also the first of its kind for an APB compressor. The control signal, in addition to controlling all aspects of dynamic range compression, also manages the compression ballistics automatically when the AUTO button is engaged.
  • All analog compression and saturation stages

  • All analog implementation of McDSP’s BITE compression mode

  • Signal dependent auto attack and release option

  • Sample accurate automation of analog processing

  • Included with APB hardware purchase
  • AAX Native, AU, VST3
Analog Saturation
The C-18 compressor plug-in performs all the dynamic range processing in the analog domain, including gain post compression (often called ‘make-up gain’). Before the analog signal is converted back to the digital domain, it is passed through a custom saturation circuit. This is useful for two reasons, the first and perhaps most obvious is the opportunity to get some analog saturation sounds!!! The second use of such a circuit is that gain levels are ‘monitored’ by the saturation circuit. Any large spikes in level will not make their way back into the mix. Instead such signals are squashed by an all analog saturation process.
The Bi-Directional Transient Enhancement mode of the C-18 creates a modified version the C-18 compression response. When the BITE mode is engaged, selected signal transients pass through the compressor relatively unaffected. The BITE mode is useful for getting more punch, pow, or bite out of a track. Because the C-18 dynamic range processing occurs in the analog domain, so does this modified compression response. Interesting results can be achieved when using the BITE mode and enough output gain to cause the signal to hit the custom saturation circuit of the C-18.
Overall compression response is controlled by the Attack and Release controls in the C-18 compressor. A good alternative to manual setting of these controls can be explored using the automatic attack and release mode enabled by the AUTO button. This mode will use signal levels to calculate attack and release times, and can produce a result perhaps more useful than user selected values.
Signal level at which compression action begins.
Automatic attack and release values are used, based on a separate detection algorithm.
The C-18 Compressor includes 3-way VU meter that can show signal level input (IN), signal level reduction caused by the limiter (GR), and signal level output (OUT).
Side Chain
Compression action can be triggered by the input channel (SC button off) or a side chain channel (SC button on). The signal triggering compression action is commonly referred to as the key input.
Compressor output (LISTEN button off) or compressor key input (LISTEN button on) may be monitored at any time. If monitoring compressor key input, it will be the audio channel selected by the Side Chain control (SC button).
Bi-directional transient enhancement. Allows selected signal spikes (transients) to pass through the compressor.

An important aspect of any APB plug-in is that the plug-in is primarily a controller. The APB plug-in takes the input audio signal, combines it with a control signal, and sends both along a Thunderbolt connection to an APB unit for processing. The control signal sets up the analog components to do the selected algorithm with all the parameter values, and the audio signal is converted to the analog domain. The analog version of the audio signal is processed in the analog domain, and then converted back to the digital domain.

By operating the APB hardware from an APB plug-in in this way, all user controllable parameters are recallable and can be saved as presets. Furthermore, because the control signal is married to the input audio signal, parameters can be updating during playback with sample accurate automation.
Sound Examples
Acoustic Drums
Drum Room
Bass Guitar
Electric Guitar
Full Mix
Male Vocal
List of all APB dealers.
Frequently asked questions about the APB.