MXR M87 Bass Compressor Problems

I decided I wanted to change away from from my TC Spectracomp compressor, to one that had the usual selection of control knobs physically on the pedal.
I also liked the idea of knowing a bit more about what was going on with the compression, so I wanted a pedal with a row of LEDs showing how much compression is being applied.
That really narrowed things down to the Boss BC-1X and the MXR M87 compressors.
Having watched A/B tests individually and against each other, to me they seemed pretty evenly matched.
I don’t particularly like the style of Boss pedals, so I bought the M87.
Well I tried it last night and it was aweful. I could not get it to work right.
On my passive Fender Jazz bass, I had to max out the input level on the M87 to get any compression to register on the display, so in effect I had no control over the input threshold.
On my active Ibanez, it worked best with the active output on the bass max’d out, though I could turn it down a little and still get some compression to register on the display and turn the input knob on the M87 down a bit. But not usable.
Seems I’m not alone with this issue, the build quality of the M87 seems variable and some people have reported you need a very high input for anything to happen. Ovnilab reports this too, though they didn’t find it themselves. Various other problems reported like units failing suddenly and never working after that.
A compressor with no control over the input dynamic range is a bit too ironic for me, so it’s going back and I’m going to get the Boss BC-1X and live with a green housebrick on my pedal board, but if it works I don’t care!
If anyone else has had problems with the M87 I’d be curious to hear thanks.

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Could check out the Darkglass SuperSymmetry or HyperLuminal too :slight_smile:

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Thanks @howard. Will take a look. Cheers.

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I love my Boss BC-1x, but I also love my SAN JUNE GB-cp.
you might want to check that one out if you want the range of controls similar to what is on the MXR M87. I find you can dial it in somewhat easier then the Boss, and it sounds a lot more like a limiting type compressor.
But the Boss rocks as well, but you can get two San June’s for the price of one Boss,
Also, you stated you hate the look of the Boss. the San June is pretty attractive.

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That Dark Glass looks cool too. And they make great stuff.

As it turns out, I may be getting ANOTHER compressor in a trade.
This one looks really interesting, it is a Compressor and a drive.

it is the VFE White Horse, an early Hand Painted one.

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Wow! So many cool boutique pedals. Look forward to hearing about this one.

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That SanJune GB-CP Optical Compressor looks interesting. I’m tempted to get one but they’re hard to find.

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You might really like optical compressors. They tend to be smoother and more mellow in their compression.

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What makes the difference?

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Ah, come on now, you said your GAS was mystical gone, as if you took some Beano or something? :rofl: :rofl: :rofl:

Well, if you must, there are more then 10 available here

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Yeah, but coming here and reading threads like this is like walking into a smoky bar when you’re trying to quit smoking.

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It’s the way they work. Optical compressors are really simple; the input signal amplitude drives a light to be brighter the higher it gets, and the compression level is set by a photoreceptor the light is shining on. It leads to a really smooth, natural sounding limiting in most of them I have heard.

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Here is a clip from an article explaining all the types of compression, it is a pretty in depth article, and goes more towards studio type compression then pedal compression, but still gets the points across.

What are they used on?
An OPTO compressor is good at taking care of macro-dynamics. If you have a song that starts quiet and ends loud a VCA compressor will do nothing at the beginning and will smash the signal at the end (depending on your settings of course). An OPTO compressor will smooth things out and will have a more consistent level throughout the song. When you want to tighten up your mix a little bit without losing transients, use an OPTO compressor on your mixbus , but be careful of pumping which will boost the low end content. To prevent this from happening you can use a high-pass filter in side-chain mode. It also works really well on bass , guitars , and vocals . But then again it depends on the performance, if the performance has lots of transients you might be better of using a different type of compression or perhaps a combination of two.

If interested you can put into a search field on any search engine “Optical compression vs FET vs regular”
and there are all sorts of websites with good in depth write ups about this subject.

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I’ll keep that idea of an optical compressor in mind for the future. For now, I’ll just keep my 2 knob MXR DynaComp.

GAS crisis averted

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Honestly the DynaComp is a fine little compressor and might be all you ever need. It’s the most used compression circuit in the world.

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Whew!!!. Beano to the rescue!!!

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Yeah, whew…

Oh look, someone on here has a DOD FX25B Envelope Filter for sale!

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