Mad Professor – Forest Green Compressor REVIEW

The Mad Professor strikes again with the Forest Green Compressor. On the surface a very simple compressor, but with a touch of magic under the hood…

There are so many dedicated bass compressors on the market that it may seem strange to look at one that was created for guitar first. Well, maybe that’s a false premise as some of the most simple and classic compressors – such as the 1176 or LA2A – work wonders on any type of source material. The Forest Green is somewhat similar in the sense that it’s simple to use and more importantly useful for compressing almost any signal.

It should be mentioned that there are two different versions of the Forest Green Compressor – a hand-wired version and a factory-made, mass-produced version. The unit I have in for review is the hand-wired version that reportedly should have a more ‘musical’ character, but since I do not have the mass-produced version to compare with, I will not dig further into any potential differences between the two versions.



mad-professor-forest-green-compressor-hw-control-knobsThree knobs and a toggle switch – that’s about it. The COMPR knob handles all compression parameters in a single twist and turn, while the LEVEL compensates the gain change happening during the compression and the TONE knob can be used for counter adjusting for tonal changes that may be introduced.

The toggle switch flicks between two fundamental modes: COMPRESSOR and SUSTAIN. Obviously, the compressor mode is all about, well, compression of dynamic spikes and peaks, whereas the sustain mode is more about bringing up low dynamics or keep notes ringing for a longer amount of time. While the latter can indeed be useful for fretless bass, for instance, it is the compressor side of the Forest Green that I find the most interesting.



white headphone with rhythm symbol

I have divided the sound clips for this review into three rounds, each focusing on the compressor mode, the sustain mode and the tone knob.


NOTE! Please use headphones or ‘real’ speakers. You simply can’t judge low-end material on laptop, tablet or phone speakers…!

NOTE! If you are on a mobile device, please turn it to landscape mode to see the knob settings of the pedal for each audio clip.




The Forest Green is not the most flexible compressor you’ll ever come across. There are no dedicated controls for ratio, attack or release and no blend option, which seem to become more and more common on effect pedals. No soft knee option and no visual indication of gain reduction or input signal.

But on the other hand, there are literally hundreds of two-knob compressors out there and compared to them, the Forest Green all of a sudden seems quite versatile. The TONE knob is extremely subtle, but once in a band mix it definitely makes a difference and is much more useful on the stage than it suggests when you noodle around with it in the store.



The second I lifted the box out of the post package, I was in for my first surprise. This pedal is HEAVY. As mentioned in the introduction, this is the hand-wired version of the Forest Green Compressor and whil I do not have the mass-produced version, I have a few other Mad Professor pedals from the factory-made series of pedals and they are considerably lighter. That said, I have long come past the point where I simply consider weight to equal quality, and I have never had any issues with the factory-made Mad Professor pedals. Where there may or may not be a difference is probably in the subtle tonal details, but again without having a pedal to compare with, I will avoid speculating in this matter.

As for the design, some quite serious design decisions were made at some point, leaving out all and any of the classic compression parameters. A one-knob solution that simply gives you ‘more’ or ‘less’ – the ‘how’ is out of your hands. But it’s not uncommon and when it works, it’s not an issue – and it works great on the Forest Green.

I have one issue that is common for all Mad Professor pedals (and strangely enough for other pedals coming from Finland such as Darkglass)… The power supply input is located right next to the input jack on the side of the pedal. Not the biggest issue ever, but I do find it annoying whenever I try to assemble or redesign my pedal board. All my short patch cables have 90-degree angled jacks and they just seem to conflict with the power supply connector all the time. OK, rant mode is now off.



Today (2015), you can buy a new hand-wired Forest Green Compressor for approximately $350. That is a lot of money, but for a pedal that does the compression job so well and also doubles as a potential always-on pedal for adding some fundamental tonal mojo, it is definitely worth considering.



Even considering the relatively steep price point, I really like this pedal. Simply because it sounds so good and I find myself using it more and more as an always-on tone shaper, which actually makes me think that I may need one more that I can use as a… compressor!



Sounds great (compressor)

Sounds great (general ‘mojo’)

High build quality



Power supply jack on the side













Leave a Reply

Your email address will not be published. Required fields are marked *