MXR M87 Bass Compressor Settings Help

[bongomania]

FWIW I am pretty sure John is correct on all counts there.

 

[JohnDavisNYC]

Compressor nerd high-4:1! (weak joke)

 

[Bubba Ghanoosh]

Compressor nerd high-4:1! (weak joke)

Hahaha!
Thanks, John and bongo!

For the record, here is Dunlop's reply to my email:

Yes, the Ratio adjusts the threshold thus adjusting the amount of gain reduction. The Input only adjusts the input gain into the circuit.
Cheers,
Derek

Derek Jones
Technical Support Manager
Dunlop Manufacturing, Inc.
​

 

[Razzmatazz]

...this means that the unit eases into compression before the threshold is actually reached, and then reaches the full compression ratio when the signal reached the actual threshold. this makes sense...

This is making sense indeed! Thanks a lot! All clear now!

 

[bongomania]

Compressor nerd high-4:1! (weak joke)

...groan...

For the record, here is Dunlop's reply to my email:

Yes, the Ratio adjusts the threshold thus adjusting the amount of gain reduction. The Input only adjusts the input gain into the circuit.​

...As though changing the input gain had no relation to the amount of compression...

 

[MostlyBass]

I also have this pedal and it took me a lot of experimentation. I also change settings depending on the volume, room, etc. At first I was a little 'iffy' about it... But now I'm a total compression convert and even bought the custom comp for my guitar.... And there's nothing wrong with changing settings based on your mood.. Sometimes I want to have a more Sheehan sound and crank it up.. other times, a little goes a long way...

Experiment, use your ears, and have fun!

 

[TheBass]

You misunderstand my post. At higher ratios, the threshold is effectively raised, so you see less gain reduction on the meter, but relative to the threshold, the gain reduction itself is actually greater, although the total g/r may be less....

This is partly why meters are great and why they suck.

For instance, slap a real 1176 on a snare drum, and at a 4:1 ratio, you will get g/r at a relatively low input gain. However, it will sound rather squishy, because it is beginning to compress at a lower threshold, but because it is a low ratio, you will still have a rather large dynamic range. Switch the 1176 to 20:1 and the needle may not move because the threshold is higher. This is for a few reasons. One reason I didn't mention is that with a high ratio and a low threshold, it is difficult to achieve small amounts of gain reduction without having the input very low and the makeup gain cranked. This is noisy and sucks for all applications.

Basically the short answer is that there is less apparent gain reduction at higher ratios for gain structure reasons, and also it's important to keep in mind that higher ratios are not necessarily intended for more gain reduction.

John

I guess this is what MXR calls "CHT Constant Headroom Technology" ?

 

[blacklariat09]

I picked one up... I have the input high (2:30) and output at unity... release at about noon and attack at about 2 o' clock.

I play a lot of 8:1 and some 12:1.

I play a little hard and have an active bass though. My goal was to pull up my high notes and also to fill out the softer finger playing in solos that I do. This seems to do it well and knock down the heavy lows in my bass and pull up the light highs.