The benefits of using a bass compressor and how to do it

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The benefits of using a bass compressor and how to do it

Words by Mixdown Staff

Bass compressor pedals and rack units to improve your bass' presence

In the ever-expanding effect pedal family, compression may just be the most misunderstood effect of them all. It’s not the source of thunderous, ground-shaking distortion. Neither is it responsible for producing the rich, shimmering nature of a quality chorus, nor the complex time altering of a feature-packed delay.

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Bass compressor

Yet for the bassist searching high and low for consistently tight tone – a lifelong pursuit for many musicians’ of the four-string variety – the compressor pedal is the under appreciated answer.

Compression explained

In the simplest of terms, a compression pedal controls the dynamic range of your bass by making the loud sounds softer and, conversely, the soft sounds louder. It’s this process of sonic squeezing that tightens the difference between louder bass signal and softer signal, thereby producing a much more consistent level of output.

This is achieved through the use a high-gain preamp and a control circuit, the latter of which informs the preamp gain based on the compressor input.

compressor pedal

MXR M87 Bass Compressor

The importance of this effect to bass tone is twofold. Firstly, it patches over and corrects sloppy precision and any lack of dynamics technique – a safety net for the player still mastering their craft. After which it’s an invaluable tool for nailing a prominent and purposeful place in a live or studio mix.

In both situations it ensures that the bass isn’t lost as a result of significant dynamic shifts and, in turn, can provide a solid dose of low-end punch.

Compressor controls

Most compressor pedals come equipped with controls that you won’t regularly see on other effect pedals. Here’s a breakdown of what to expect, and how to get the most out of each parameter.

compressor pedal

Boss BC-1X Bass Compressor

Ratio defines the rate at which the signal is compressed and is commonly set between 2:1 and 4:1. It works in conjunction with threshold, which dictates the decibel level at which the compressor will be triggered into action. With a low threshold the compressor is going to kick into gear without playing very hard, while a higher threshold will require significant strumming in order to engage the compressor.

If we set threshold to -6dB, then the compressor will only soften signals that are louder than -6dB. At a ratio of 2:1 for every 2dB above the -6dB, the volume will only increase by 1dB.

compressor pedal

Darkglass Electronics SSCOM Super Symmetry Compressor

Attack decides how quickly the compressor will react to your signal. A fast attack ensures that the entire peak is reduced by your chosen ratio, while a slower attack will allow some unadulterated signal to pass through before the compression is engaged. By increasing the attack time and lowering the threshold you can add more punch to your bass tone.

In comparison to attack, release allows you to determine when compression stops once the compressor has been triggered. It’s important here to find the right balance – if the signal is compressed for too long it will lose traction and punch, while if it’s too short it can create unwanted undulation.

A compressor for every occasion

When searching for the right compressor for you the greatest distinction can be made between rackmount units and pedal compressors. With the former usually being of vintage design and of greater quality, and the latter, cheaper, more accessible, and convenient.

Universal Audio Teletronix LA-2A

The rackmount Teletronix LA-2A is a vintage-style tube compressor that utilises an electro-luminescent panel and a couple of photo-sensitive resistors to reduce gain levels. With minimal controls and a fixed 10 microsecond attack it’s renowned for its gradual decay, which after the initial 60 microsecond release, varies from between 1-15 seconds depending on the length and volume of the incoming signal.

A classic rackmount solid-state option is the UREI 1176, equipped with an obscenely fast attack – as low as 20 microseconds – and push-button selectable ratios of 4:1 and 8:1. At times throughout their careers it has even been the compressor of choice for The Rolling Stones and Led Zeppelin.

UREI 1176

For many bass players the most likely option is going to be a stompbox. Here it’s hard to go past the Keeley Compressor Pro (for both guitar and bass), which couples your standard compressor controls with a knee hard/soft switch that controls how sharply compression is applied.

Keeley Compressor Pro

When switched to soft, the compression gradually increases as the input level approaches the threshold, delivering a more understated compression that allows for a greater dynamic range. Alternatively, when switched to hard, the signal undergoes the chosen ratio of compression the instant it crosses the threshold, delivering a more aggressive, pronounced compression.

Beyond Keeley, Aguilar, DigiTech, EBS, Electro- Harmonix, MXR, and Markbass all manufacture compressors aimed specifically at bassists.

Looking for info on the holy grail of compressors. Read more about Fairchild LLC.