The Compressor MKII makes a few important changes to our classic compressor.  It uses the same JFET circuitry but here is a list of things that changed.  Do these changes justify a new purchase if you have the old compressor?  I don't know, that's up to you cause the original compressor still works great!  

1. Redesigned smaller enclosure with top mount jacks

2. A tilt eq style tone knob

3. High pass filter built into the side chain that can be toggled off or engaged at 120Hz or 240Hz

4. The ability to power on bypassed or engaged 

5. 1/8" TRS send/return for the sidechain insert

6.  Separate gain reduction and input monitoring