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Union Tube & Transistor Lab Compressor Review

It doesn't get much simpler than this. Just two knobs. One for volume/makeup gain (the left knob) and amount of compression (the right knob).

The Union Tube & Transistor Lab is an optical circuit with relatively fast attack and slow release timing. I must admit that fixed attack and releasing timing sometimes turns me off and so I approached this compressor with some hesitation. Would it ultimately just squish too much no matter how I adjust? Would I lose all of my transient attack?

And then there is the name "Tube & Transistor". It's not really a tube or transistor type pedal. Would it exhibit tubey goodness anyway?

Ok, yes the circuit is set to grab pretty quickly. But if you are the type that prefers slow attack (allowing more initial transient through) don't rule this one out. At lower compression levels, somehow the Lab compressor manages to not feel to grabby. In fact, it feels very nice playing quick rhythmic patterns as well as slow, smooth, and even patterns. It's as if the compressor adapts to your playing style. Quite nice actually.

It's got this special gooey sound going on. It definitely smooths and evens out your playing but in an inconspicuous way.

At lower compression levels it is definitely doing something to fatten or make your sound "bigger" but not in a highly colored sort of way.

At higher compression settings it totally squashes your signal but not with a lot of dip and swell. If you are in to the squashed thing it feels pretty natural.

My preferred setting was with the compression knob between 9:00 and 11:00 for obvious compression but still very organic and natural. I wouldn't say the Lab is highly transparent, but it isn't highly colored either.

I noticed no loss of highs or lows and it is very quiet. Not quite Markbass Compressore or FEA quiet, but very quiet.

Speaking of the Markbass Compressore, I'd recommend the Union Tube & Tranistor Lab compressor to those that like the Markbass but want something considerably smaller. There are definite similarities in sound and feel between the two. Of course the Lab lacks the range of dynamic controls but you might not need them anyway. I'm a fan of the Markbass and I'm not sure the Lab compressor would bump the Markbass Compressore off my board permanently but it has already for a couple of gigs. With its top mounted power and input/output jacks and smaller size the Lab compressor is much more pedalboard friendly.

The Lab sounds very, very good. I've used it in various settings and it sounds great everywhere. Direct in an FOH scenario and in front of an amp and cab. Makes my IEM's sound killer.

I really like the multicolor LED. It illuminates green indicating power to the pedal. But the LED transitions from green to yellow to red as more gain reduction takes place. It is similar to how the LED of the Diamond works, but better in my opinion. The LED on the Lab seems to intensify as energy is built up so it isn't strobing between green, yellow and red. As your playing ramps, so does the LED. Pretty neat.

The pedal is quite lightweight. The circuit board inside takes up a small percentage of the enclosure. It appears well made and the enclosure itself feels quality.

Foot switch is true bypass. Power requirements are 9V @40mA.

Well, there's not much else to say. The LED monitoring works well. It's built well. It sounds fantastic. It would not be the best choice for those wanting total control of your compressor. You won't get that here. But for those wanting big tone with ease of use, with just two knobs, it doesn't get more simple.

Retail price is $300.


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