Extensive compressor reviews and FAQ

This chart is a work in progress. Eventually I will add this type of rating system for all 140+ comps I've reviewed.
Click here for an explanation of the grading system.

back to the top
 

An explanation of the grades:
 
= Excellent, among the best.
= Good, better than average.
= Average (not bad at all, just "middle of the road"; most qualities of most compressors are close to average).
= Poor, worse than average.
= Really bad.
 
Peak limiting = how well and cleanly it stops big signal spikes, to protect your speakers and avoid unwanted clipping.
 
Transparency = how little it alters your tone.
 
Squash or sustain = how much your signal gets mashed or squeezed to produce an audible effect.
 
Noise = a combination of: how much noise it produces on its own; how vulnerable or resistant it is to ambient electromagnetic noise; and how much it amplifies any noise already present in your signal chain.
 
Low frequencies = how well it passes and handles the lows, and how full they sound.
 
Value for the price = the "bang per buck", how much functionality or quality you get for what you pay. More than any other grading quality, this one is relative to other comps in the same price range or offering the same features. For example the DOD Milkbox and the Markbass Compressore will both get "excellent" value grades; the DOD is certainly not as good of a compressor as the Markbass, but considering the DOD costs about $35 used, it's a terrific value. On the flip side, there are some really great-sounding or popular pedals that will get average or poor value grades because their prices are quite high for what you get.
 
back to the top  
Explanation of the more detailed ratings:
 
Versatility = how many different tones or compression qualities it can achieve.
 
Input range = how well it handles different instrument signal levels, from low/quiet to high/loud. This also covers whether the comp has a threshold or input gain control.
 
Ease of use = either it has fewer knobs, or it can mean the controls are intuitive and effective without requiring a college degree in knob-tweaking.
 
Warm/fat/dirty = the flip side of transparency--it means how much the device colors your tone, fattens it, or adds soft distortion.
 
Clean smoothing = whether it can gently massage your signal into shape without messing with your articulation or dynamic feel.
 
High freqs = either how high the frequency range goes, or how good it sounds in the upper end. Be aware that sometimes guitarists disagree with my opinion of the highs, as they often seek a lot higher and brighter tones than I do.
 
Construction = the ruggedness and quality of how it was made, and this includes both the external parts and the internal guts.
 
Bypass quality = how transparent the bypassed signal sounds, and how solid or well-designed is the bypass mechanism. A 3PDT "true bypass" switch, with no other anti-pop circuitry, will just get an "average" rating.
 
Extra functions = either non-compression features such as overdrive or EQ, or unusual compression controls. The grade reflects how useful, well thought out, or good-sounding these features are. Most comps will just have a "-" in this space, since most do not have any extra or uncommon features.
 
Meters/indicators = whether there are any LED lights or "needle" VU meters that indicate how much compression is occurring, and how good or useful that metering is. If it only indicates whether your signal is over the threshold, it will get an "average" grade. Comps that have no indicators (like most pedals) will just have a "-" in the grade box.
 
Power convenience = how easily you can power the device with standard/common inexpensive power supplies. For pedals this means whether it takes a Boss-type barrel plug and center-negative 9VDC. If it can run on a daisy-chain supply and not have any noise/hum interference from other pedals, it will get a better-than-average rating. The only pedals that will get a grade of "the best" are the rare few that can run on multiple different types of power source. For rack units, "the best" is an internal power supply with a detachable IEC-standard power cord.
 
Size/weight: For pedals, an "average" rating is a Hammond BB box (Diamond, Barber, Aphex size), and a "best" rating is a B box (MXR, EBS, Keeley size); "good" is in between them (Boss, Aguilar). "Poor" is bigger than a Hammond BB, up to the Markbass size. "Bad" is anything bigger than the Markbass (Vox, Retrospec). For rack units, "average" is 1RU (1.75 inches) high, and about 9 inches deep. "Poor" is 1RU but deeper than 9", or particularly heavy; while "bad" is anything greater than 1RU in height. "Good" is 1RU and much less than 9" deep; and "best" is 1RU height and only 1/3 or 1/2 rack width.
 
back to the top