When using compression and EQ together on the same source, which one should I put first? You should try it both ways and pick which sounds better to you, but here is the basic philosophy: Compressor’s try to turn down louder signals, right? So boosting frequencies before a compressor, will inevitably cause the compressor to react more easily, because the signal will have become louder going into the compressor. For example, boosting 60 Hz on a kick drum and then compressing it will likely just cause the compressor to react much more. You may like the sound of this, and it might be exactly what you’re looking for – if so then that’s great. However by compressing the signal first, you can even out the dynamics of the sound first, and then you can sculpt the sound with EQ afterwards without affecting the dynamics of the signal. I generally cut frequencies that are not part of the overall timbre of sound I am looking for and then will either use compression as a leveling device or perhaps more of an effect that changes the envelope of the sound. YMMV.