Lars Lentz Audio™

I use the Purple Audio MC-77 FET compressor plugin from Plugin Alliance to control and enhance my drums and other instruments, and here is how I set it up and use it.

FET Compressors

The Purple Audio MC-77 is a FET-type compressor, so below is a bit about FET compressors in general and why you may want to use them.

What Are FET Compressors Typically Used For?

Audio producers use FET (Field Effect Transistor) compressors as they process powerful and dynamic audio sources. These compressors remain popular for the following applications:

• Drums and Percussion: Their fast attack and release times make them ideal for taming transients and adding punch to drums, snares, and other percussive elements.
• Electric Guitars: The use of FET compressors adds both energy and sustain to audio tracks which makes them suitable for electric guitar productions especially in rock and heavier genres.
• Vocals: They are often used on vocals that need to cut through a dense mix, providing both control and character.
• Parallel Compression: Due to their aggressive and colorful sound, FET compressors are commonly chosen for parallel processing to add vibe and excitement to tracks.

Defining Characteristics of FET Compressors

• Fast Attack and Release: FET compressors are known for their lightning-fast response, which allows them to catch and control sharp transients effectively.
• Color and Character: Unlike some other compressor types, FET compressors impart a noticeable “color” or “vibe” to the audio, often described as bright, punchy, and energetic.
• Emulation of Tube Sound: The transistor circuits in these compressors emulate the warmth and saturation of classic tube compressors but deliver a modern aggressive tone.
• Aggressiveness: The design of FET compressors maintains original transient signals, so sounds appear more upfront in the mix and gain additional punch.
• Versatility: Their clean, fast, and flexible dynamic control makes them suitable for buss compression while they excel on aggressive sources.

FET compressors are valued for their speed, punch, and character-enhancing capabilities in audio production. Music producers use these compressors for drums, guitars and vocals to enhance their output while mixing energy and excitement into the track. Their defining traits are fast response, colorful sound, and the ability to maintain transients, making them a staple in both classic and modern music production workflows

Purple Audio MC-77 Plugin

This is a plugin version of the Purple Audio MC-77 hardware compressor which is a recreation of the 1176 E from UREI.

I use it mainly for individual instrument compression and character enhancement, so I put this on my drum bus, drum instrument channel(s), or another instrument like a synth or bass.

Drum Bus Setup

Below, I will describe my primary use and setup process, which is on a complete drum kit for compression and character.

To understand how to start using the compressor properly, I read the hardware manual (below), which has a starting point and suggestions for the steps needed to begin use.

Section 8 of the manual gives the operating instructions and a great starting point which I adapted into the plugin as my starting point.

Here are the starting point settings shown in the plugin version:

Below is a video of setting the compressor for a drum kit to achieve a fuller sound with more character.

Note how I followed the basic steps:

1. All knobs (in the purple area) are at mid positions to start.
2. GR is depressed to be able to see the gain reduction.
3. Adjust the input knob to get some gain reduction (this is up to you to decide how much).
4. IO button and OUT are then not depressed to be able to see the output.
5. Adjust the output knob to stay around 0 dB on the VU meter.
6. Adjust the attack counter-clockwise/anti-clockwise (slower) and the release clockwise (faster) to get a sound with more character.
   • The attack is 20 microseconds at position 7 and 800 microseconds at position 1.
   • The release is 50 milliseconds at position 7 and 1.1 seconds at position 1.
7. Try pushing in different ratios – either single buttons or multiple buttons by depressing the hold button prior. With all buttons in and the attack

To go further toward enhancing the sound, you can then experiment with linking the input and output and adjusting the input upwards (output will similarly decrease). This drives the unit harder while maintaining the same output levels as previously set. Below is what it looked like after I adjusted the input and output.

Note that the VU meters seem to be calibrated to 0VU=-14dB rms. I checked this using VUMT by Klanghelm.

The manual for the plugin does not have the setup instructions like the hardware manual does, but the plugin manual describes a lot of extra features available in the plugin that are not in the hardware. These are mainly on the bottom panel. I do not use these and leave the settings as shown below.

Here is the manual for the plugin:

You can also change the compression ratio by choosing either 4, 8, 12, or 20:1 ratios via the push buttons. Depressing the hold button will allow multiple button selections and can be quite interesting to experiment with. The “all in” setting was popular in the hardware version and gives quite the compressed sound.

Controlling Transients

You can easily have excessive transients when completing the setup like I describe above, but if this is the case, there’s a very easy fix for that. And, it will sound very transparent and natural. I often know I have excessive transients by the yellow lamp lighting on the meter of the MC 77.

Simply adjust the attack and release to calm the transients.

Above is one of my settings for a particular drum track. You can see I have the attack turned upward (6.1) and the release at about midway (4.7). Doing this took my transient issue away yet still maintained a suitably punchy drum bus.