Compressor pedals are perhaps the most overlooked and underrated effects pedal for the guitar. Since they’re not as obvious as say, overdrive, they tend to be forgotten by those building their first pedal collection.
However, in many cases, they should actually be one of the first ones you buy. Why? Read on dear friend, read on.
In this article, we’re going to get deep dive into these pedals, how they work and which are the best compressor pedals available today.
At a Glance: Our Pick of the Best Compressor Pedals for Guitar
- Wampler Mini Ego
- Xotic SP
- Boss CP-1X
- Behringer CS400
- Empress Effects
- MXR M76
- Electro-Harmonix Black Finger
Note: Clicking the above links will take you to further information, current prices and customer reviews on Amazon.
Here’s what we’ll cover, jump straight to an area of interest or for full effect, read from top to bottom.
- What is a Compressor Pedal?
- Compressor Pedal Controls
- Product Round-up & Reviews – Best Compressor Pedal
- So, Which Should I Choose?
What is a Compressor Pedal?
Compressor pedals create sustain without adding distortion or clipping the sound. They also control dynamics for recording or to keep from overdriving sound equipment. They do this by detecting the volume of the signal and controlling how loud or soft a signal gets. If the signal starts to fade, it increases the volume. It also or limits the signal if it’s too loud.
These pedals can also add some volume and can act as a booster, helping to get more tone from a tube amp that doesn’t have enough gain or distortion.
Sustain Without Distortion
Compressors also have the ability to increase the sustain of notes beyond the instrument’s usual capability.
Some have a dedicated sustain knob, whereas some enable sustain via their attack/release knobs. You can alter the attack and release of your compressed sounds to make the notes last longer.
If you find that when you’re performing, some sounds just aren’t cutting through, while some are blasting people’s heads off, then compression will help even out your sound. It will reduce the overall range in volume so that the listening experience for you and your audience will be more stable.
It won’t automatically make you play the right notes of course but will fix inconsistencies in how forcefully you pluck each string in an arpeggio or chord. They can also help you to avoid losing notes in a wall of sound when playing rapidly such as with sweep picking.
Sometimes ‘squashed’ guitar sounds are desirable for genres like country music or for ‘chicken pickin’’ guitar playing. ‘Squashed’ means to have a very even tone and attack, with very few dynamics.
Using the highest notes on your guitar can often lose a lot of volume compared to playing the same lick in the middle. A compressor pedal is able to boost those higher notes so that you can use them just as freely.
Here’s a decent summary of how they sound:
Bad for Expressive Music
For a start, they get a bad rap sometimes for ‘squeezing the life’ out of your playing.
Expressive genres like blues often rely on the dynamics of the player. Most bluesy players use their picking technique to control their volume, which becomes an important part of the music and the performance. Using a compressor will neutralize this, which can, in turn, remove the emotion from the sound. This can also dull your sound as they squeeze your dynamics closer together. This can result in a ‘flatness’ or lack of brightness.
That said, some blues players do use them largely due to the benefits they have on sustain. It depends on how important the dynamic range is to your sound.
Hum And Hiss
If you leave your pedal on, or it doesn’t have true bypass when it’s out of use, this can lead to humming or hissing sounds in your signal. On its own, this doesn’t usually cause too much of a problem on stage but it can add to the hum of other pedals. It’s also something to be absolutely avoided in a recording situation.
Compressor Pedal Controls
Here are the common controls you find on many of these gizmos.
Threshold, sometimes called ‘input level’, is how loud the signal needs to be before the compressor kicks in. In other words, the threshold is the point at which you want your volume to peak. If you set your high threshold to, say, 2db, anything above that will be reduced by the amount you set it to be reduced by. If you set this somewhere that’s not too far away from your lowest volume, this will make all of your notes sound similar in terms of gain, enabling consistency and clarity.
Release (Sustain) Time
Release time is how long it takes to remove the effect once the signal is back below the threshold. Short release time can enable more natural sounding performances, however, sometimes you might need longer release time to achieve smoothness between compressed parts and non-compressed parts.
Tone controls usually increase the high end. Compressing the peaks can often make the guitar’s tone duller as it reduces the higher end frequencies. Lifting the high end compensates for this.
The attack control can come in really handy, as it determines how quickly your compression kicks in. Sometimes, you don’t want it to work straight away, as it will take away from the feeling of the music. Adjusting your attack so that the effect is a little slower acting can be the remedy to what would sound soulless.
The best way to think about Ratio is ‘how much to turn down the volume’. For example, if the ratio is 2:1, for every 2dB the input signal increases, the output increases by 1dB. Musiciansfriend.com have a decent guide that explains all this.
Blend Control / Parallel Mix
Blend or parallel mix controls allow you to combine the compressed signal with the original signal. These controls let you set how much of each signal is coming through so that you can keep some of your original tone while still retaining the benefits of compression.
True bypass means that when the pedal is switched off / out of use, the input leading directly to the output without any interference from the circuitry. This will keep your tone transparent as it runs through.
Multi-band features allow you to alter which frequencies are affected. This can be really handy for those who want consistent dynamics when they’re playing open strings, but need to exhibit some emotion in the higher frequencies as they solo up the fretboard.
Product Round-up & Reviews – Best Compressor Pedal
Wampler Mini Ego
The Wampler Mini Ego is a small, voltage-controlled effects box which has volume, blend and sustain dials. These allow you to maintain some of your original signal, while still reaping the benefits of compression in terms of dynamic control and increased sustain.
It also has a tone switch and an attack switch. These allow you to quickly boost your high or low-end frequencies and to alter how quickly the compression kicks in.
Although these switches are on/off switches, rather than highly controllable dials, this will suit those who like to keep things as simple as possible.
This stompbox is perfect for the player who doesn’t want to overthink or get too techy and would like something that’s small and sturdy. It’s also a good option for those who want to boost their lower sounds, rather than to reduce higher peaks.
The Mini Ego might be less suited to those who are interested in taming down their higher peaks; pedals with more options regarding ratio and threshold are better for that.
- Extremely small, sturdy and easy to use.
- Contains true bypass.
- Versatile in terms of genre: works equally well from funk to chicken pickin’ to sustained lead lines.
- You can’t power it off batteries.
- The attack and tone controls are very limited.
- The LED is fixed so there’s no visual representation of the compression.
The KongPressor is an optical compressor, which has a naturally slow release that contributes to its smoothness and natural sounding compression.
It also works as a super-clean boost if you turn the ‘squeeze’ dial down, and it has attack and release knobs as well as volume and chime (tone) dials.
There’s a transparent buffered bypass which completely eliminates the effect. That said, it’s the kind of pedal that makes your guitar sound so good, you probably won’t want to switch it off.
It’s perfect for those who want to fatten their clean guitar sounds, and for those who lean towards vintage tones and looks. It’s the smoothest sounding of all the products listed here, so is the obvious choice for those who like to keep a natural sound.
It’s less suited to those who want to use compression as an effect, or who might want to use it to reduce their louder signals.
- Attack and release knobs give you full control over how quickly the compression kicks in and how long it lasts.
- Eye-catching design makes it a welcome addition to any pedalboard.
- Optical maintains the signal’s integrity.
- Although it has a transparent buffered bypass, its lack of true bypass won’t suit those who are committed to this feature.
- The design might not suit everyone’s taste.
- The LED is fixed so there’s no visual representation of the compression.
Like the Wampler Mini Ego, the Xotic SP is a mini, voltage-controlled unit.
It is also extremely simple. There are blend and volume controls, as well as a low-mid-hi switch. It can enrich your clean signals effectively whilst maintaining your natural sound. The low-mid-hi switch is also easy to quickly shift.
It’s super-easy to use, and unlike most mini pedals it can also be powered by a battery as well as an adapter.
It will suit those who want a simple unit to add something to their softer sounds, which doesn’t require much setup. It will be less suitable to those who want a large amount of control over their compression, or to those who are looking to add sustain to their notes. The lack of control over attack and release makes it suited to enhancing clean, soft signals above anything else.
- Extremely small, sturdy and simple.
- Contains true bypass.
- Can be powered by batteries or 9V adapter.
- The simplicity of this stompbox will frustrate tech geeks and those who require more control.
- It is more susceptible to humming than some others on this list.
The BOSS CP-1X is a completely different kind of compressor which uses “multi-dimensional processing” to analyze your guitar’s signal in multiple ways, as you play.
It uses intelligent software to ‘listen’ to your playing and takes into account different strings, neck position and whether you’re playing single notes or chords.
It’s used by legends including David Gilmour, The Edge, and Bonnie Raitt, mainly due to the fantastic effect it has on sustain as well as compression ability.
This pedal has attack, ratio, level, and compression dials, and also LEDs to show the current level of compression at a glance.
It’s perfect for players who want to sound anything like Gilmour et al as well as for players who like to get into the technological side of their guitars’ effects.
It will be less suited to those who like to keep it simple and are looking for a quick-fix clean boost for their country sound. That’s not to say that it doesn’t work extremely well for country music, you’ll just need to take some time over setting it up.
- Extremely attentive technology analyses your notes as you play them.
- You have a high level of control over your attack and ratio via the dials.
- Unlike many other products, this one doesn’t muddy your tone.
- It can be a bit difficult to get your head around to start with.
- It doesn’t contain true bypass.
Behringer’s CS400 is a cheap and cheerful unit, but don’t let that put you off. Although it comes at a fraction of the price of other products in this round-up, the CS400 isn’t short of features. Behringer has made an excellent budget-friendly unit here, providing amazing value for money. Although this pedal may not be the absolute best of the best, it punches far above its weight class.
There are attack and sustain dials which give you controllability over how much compression you use, and there’s a level knob which you can use to enable a volume boost or to keep things even. There’s also a tone control so that you can boost any high-end sounds which get lost.
It will suit the guitarist on a budget who wants to tidy up their dynamic range on stage. Although it isn’t as sturdy or as silent as some other pedals, it does the trick. Pedals which cost eight times as much will perform at a similar level at moderate settings, although you will begin to notice the difference as you turn everything closer to the max.
It will be less suited to those who are going to be on the road a lot, as it’s made from plastic and won’t fair well to getting tossed about.
- Extremely budget friendly
- Works as sustain or volume boost
- Tone control lets you highlight different frequencies
- It’s not that robust
- No true bypass and no sidechaining
- Can cause undesirable noise
The Empress Effects is an analog, FET (field effect transistor) effects machine, which works wonders for your tone. It is a sturdy unit with 5 dials, two toggle switches, and a foot switch.
There are input and output controls, as well as attack, release and mix controls. These allow you to decide how much of your original guitar goes in, how quickly it’s compressed and released and how much comes out.
It has true bypass, so when it’s not in use it isn’t affecting anything, and there’s an option for parallel compression here which will suit those who want to keep their natural tone. It’s also the only one in the list to have a side chain, which allows other instruments or effects to affect the sound.
It will suit those who want ultimate controllability over the effect/process and it’s perhaps the most well suited to recording from this list. It’s also the most suited to those who are looking to reduce, rather than increase volumes, thanks to the input knob which works as a threshold. It offers a lot of features you wouldn’t expect to find outside of a studio.
This will be less suited to those who want a simple, starter pedal. It’s also not going to be one for people on a budget.
- High controllability with multiple knobs and a sidechain option
- The input knob works as a threshold which makes it easy to set the peak volume
- There are handy LEDs to show you what’s going on
- It’s expensive
- No battery power options
- There are no knobs to control the sidechain exclusively
As with most elements of audio engineering and music production, the level of sophistication and quality that can be achieved in a studio is on a very different level to what you’ll typically be able to reproduce live without having a costly and carefully controlled environment.
The MXR M76 is a valiant attempt at making sure you can tap into this wherever you are. If you’re going to be playing in small venues without huge budgets to spend on sound systems, this pedal is one that you’ll be glad you have. In terms of what it offers, you have all the standard controls along with separated input and output levels. You also get excellent visual monitoring and a broad range of ratios.
- Each note is clear thanks to the Constant Headroom Technology
- Individual input and output levels give you fine tune control
- Very clear visual monitoring with a ten-part LED setup
- No sidechain options
- Expensive, but fair for the quality
- No 2:1 ratio option
Electro-Harmonix Black Finger
This is one of the few genuine tube compressors out there, giving a very distinctive character without spoiling the tone you’ve been painstakingly perfecting. There are a lot of different sounds you can get from this thing, plus this doubles up as a bass guitar compressor, although the actual controls are fairly limited.
- Effective with bass or guitar
- No unwanted noise
- Simple to use, but very flexible
- Repairs can be expensive if one of the tubes breaks
- Needs a specific type of power cable only supplied by Electro-Harmonix
So, Which Should I Choose?
As you can see, there are a wide variety of products out there to suit all kinds of players.
The Empress Effects pedal is the premium choice and gives you ‘studio quality’. There are a fantastic amount of controls on this model, and its sidechain option gives you the option of feeding additional instruments into the pedal to influence the sound. The sound quality of the Empress Effects is excellent too, having minimal tone coloration and true bypass.
On the other hand, if all you need is something cheap and cheerful to help you clean up your sound a little and don’t want to break the bank, the Behringer CS400 is your best bet. The MXR M76 is also relatively simple, although it offers more hands-on experience with exceedingly good sound quality.
If you cannot stand the way modern compressors sound and want to get the real sound of a tube one, the Black Finger is king. Unlike most tube units, it can use up to 300 volts, the two optical compression methods give very different attacks, plus it doubles up as a bass guitar compressor.
The BOSS CP-1X is the one with the best sustain and is favored by no other than Dave Gilmour.
If you’re after something small and simple, with an impressive boost, the Wampler Mini Ego is the obvious choice. The Xotic SP is similar and is also the easiest to use out of all these products.
The Orange Kongpressor is the best for vintage tones and is the one that’s most suited to leaving on throughout a gig, to enhance your overall sound.
Whichever compressor you decide is right for you, we hope that this guide has helped you and that you have fun squashing your sounds!
Ged is Founder and Editor-in-chief at Zing Instruments. He’s a guitarist for London based gypsy jazz band ‘Django Mango’ and a lover of all things music. When he’s not ripping up and down the fretboard, he’s tinkering with his ’79 Campervan.