Compressor box

I used the Spectrum Analyzer app on iOS with the Fast Fourier transform analysis. The samples were taken with the phone microphone aimed at the compressor from about four feet away. Note the significant decibel readings as well as the frequency drop off.
This isn't a completed project at this point but the greater parts of it are done. I still will be adding a floor with dampening lining, casters, handles on the lid and sides, and hinges to the lid.
Having built this unit there are a few improvements I would make in a new build. Use 1" MDF, more space on all sides, use a more dense sound absorption behind the egg crate to absorb more of the lower frequencies, possibly similar baffles on intake and exhaust sides.