This newer offering from Roland/Boss looks familiar taking on the same die-cast chassis, the company's conventional foot switch, and screw for quick battery removal. It has that same tough, rugged feel that Boss pedals are known for.
There are four controls providing fairly flexible control and a real nice 12-LED gain reduction meter.
The Ratio knob adjusts the amount of compression that is applied to the input signal. All the way to the left is effectively 1:1 or no compression. The effect becomes greater as you turn the knob clockwise. I'm not sure what the full range is but it seemed fairly wide though I would not select this pedal as a peal limiter. Sweet spot for me was between 10:00 and noon.
The Threshold knob adjusts the signal at which the compression begins to take effect. Turning the knob left (counter-clockwise) means the effect activates at a lower signal level. Sometimes the threshold control on a compressor can be tricky to dial in. Not so here. In fact, the threshold knob works fluidly across the whole range and in coordination with the gain reduction LED meter it is very easy to understand just what the compressor is doing. Nice!
The Release knob adjusts the timing at which the device stops compressing after it is triggered. Turning the knob more counter clockwise shortens the release time making individual notes more prominent. Rotating more clockwise produces a smoother more connected sound. Sweet spot for me was straight up at noon providing a nice balance of sustained notes when I wanted it and enough articulation to play faster and fluid lines. Maxing out the Release knob provides plenty of sustain and has a real nice feel.
The Level knob adjusts the output level of the pedal. There is plenty of gain on tap and I found unity to be somewhere around 11:00.
There are definite similarities between the BC-1X and the MXR M87/M76, Empress, Keeley Compressor Pro, and even the new Becos CompIQ Mini Pro. Each of these compressors feature pleasing gain reduction meters which is a real nice feature in small pedal board capable devices. There are also similarities in in the general feel and tone of these pedals too. Like the others mentioned, the BC-1X fits in to the more neutral, transparent camp of compressors.
There are some distinct differences though. Most notably the fact that the BC-1X is a multi-band compressor meaning the instrument signal gets split into two or more frequency ranges using a crossover. Each band's signal has its own compression engine and then the device mixes the signals back together. You can read more about multi-band compression at Ovnilab. Boss calls this MDP for "Multi-Dimensional Processing" and it is a digital process in this pedal. It is unknown how many different bands are used in the BC-1x. The objective though is that bass' low-frequency content is more "energetic" than higher frequencies and multi-band compressors can help reduce the unnecessary triggering of compression be being less sensitive to low notes. There is no control over the crossover points though. The magic is baked in to the digital algorithms inside.
How does it work in real world use?
Well, it definitely has a bright articulate sound that is quite transparent and smooth.
There's a fair amount of interactivity between the Ratio, Release, and Threshold knobs so I found I needed to spend a fair amount of time getting to know the pedal. It isn't really a "tone magic" device which to me often means more of a baked in EQ effect. The Boss BC-1X does what you would expect but I would say adds some nice subtle sheen or polish to the tone. The low end response is solid and I would describe it more as tightening than big or fat. To my ear, there is maybe some enhancing of the mids which is where the magic is for bass guitar anyway. I never felt like notes were choked anywhere up and down the finger board. From highs down to the low B of my 5 strings the BC-1X did what I expected it to do keeping notes even, and uncolored. I also never felt like the BC-1X erroneously handled big spikes in sound. It was more than capable of accommodating subtle easy finger style to heavy handed finger style.
This could easily be an always on compressor for me because it is never in the way but just makes everything better.
Compared to the MXR M87/76 I don't think the ratio range extends as high but the MXR only offers 4 present ratio settings. Compared to the Empress and MXR the BC-1X lacks control of Input signal and attack though the attack range of the MXR is quite fast anyway and is limited in that regard. The Empress also has only three preset ratio settings. The Empress also provides the ability to blend in some dry uncompressed signal which may or not be a desirable feature for you. The tiny Becos has a more limited gain reduction meter range but offers control over hard/soft knee and has the ability to blend dry signal. The Becos offers only a fast or slow release setting activated via switch. The Keeley Compressor Pro offers control of Threshold, Ratio, Attack, Release, and works well as a Limiter. It also offers selection of hard or soft knee and has a single color gain reduction meter. The Keeley and Empress are considerably more expensive though and bigger. The Boss BC-1X is the only multi-band compressor of this bunch. All of these are in a similar tone space though.
There's also the multi-band EBS Multi Comp which is capable of adding more color but it lacks the variety of controls of the others listed here and also only has a single LED for gain reduction metering.
Then there is the FEA DB-CL dual band compressor limiter with wide range of control for each band but it is much more expensive, more complicated to use, and bigger. It too uses a system of single LED's for gain reduction metering.
I'd prefer to have control over the attack qualities of the Boss B-1X. That's probably the single biggest weakness of this pedal in my opinion. That being said, the magic inside was pleasing enough for me and I was content to do without a separate attack knob. I don't know if a higher ratio also triggers a faster attack? Possibly, but even at higher ratios I felt like I still had enough initial attack [bite] to satisfy. I think this would be a great compressor for bassists who frequently play with a pick or slap style. It has that bright articulate response that sound satisfy those playing styles. Don't think processed or unnatural though. While this isn't a "tube tone" compressor, it has enough warmth to satisfy but has a punchy quality.
If you are looking for a rugged pedal with great LED metering that is easy to use and provide nice tightening of your tone the Boss BC-1X Bass Comp is a great option. Plug it in, start with Output at 11:00 and the other three knobs straight up at noon. You'll be met with nice smooth, unobtrusive natural compression. Then tweak as desired.
The row of 12 LED's is very responsive. Internally, the pedal is boosted to 18 volts (use only 9 volt power supply). I had no issue with headroom with any of my basses including a high output G&L L2500. The screw at the rear of the foot switch makes for fast battery changes. The Check indicator LED shows whether the effect is on or off, and also doubles as a battery check indicator.