The Keeley 4 Knob Compressor and the Pigtronix Philosopher’s Tone represent two entirely different “philosophies” if you will, on what a compression pedal should do. The Keeley is all about subtlety and nuance. While playing soft, the Keeley gives you room to add the subtle nuance that makes guitar playing great without squashing your signal to death. It’s not until you really dig in… and dig in hard, that you start to hear the “ceiling” of Keeley’s compression. You might not even really appreciate the pedal until you turn it off and realize how much it was improving your tone. I shall label this approach the “good compressions should be seen and not heard (too much),” approach.
The Pigtronix takes the exact opposite approach. I shall call it the “look at me, I’m a compression pedal,” approach. The Philosopher’s Tone compresses hard. Whether you’re playing soft or hard, the squash is always there. This isn’t necessarily bad. If you are looking for the “effect” of compression, then this is your pedal. Pigtronix throws in a few extras to sweeten the pot, like a “grit” knob that adds some fuzz to your signal, and it beats the Keeley in the looks department with its Zen sunrise casing.
So which is better? Well, that depends on what you’re looking for in a pedal. I’m of the camp that a good compression should mostly stay out of my way so I’m in the Keeley school of thought. There are times however, when you really want a squashed sound and that’s where the Philosopher’s tone will do what the Keeley won’t. – Matt C.