I've used the MXR Studio Comp for years. Just a few days ago, I picked up a used Empress Bass Comp and the comparison has been interesting.

I set both compressors to 4:1 ratio with a fast attack and fast release. (Note: the attack and release controls are opposite on MXR vs Empress; on MXR, faster is clockwise, counterclockwise on the Empress). I set them for roughly the same amount of compression and matched the output. Mix, SC HP, and "Tone + Colour" are all off on the Empress. Recorded...

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