Genius! Thank you for sharing this! Two follow-up questions if you don't mind (and I can move this over to a private message since I am getting off topic if you'd like): Since this extends past the original box, does this affect the overall sound quality of speakers (diffraction from baffle edges)? Can fabric like this be used to also cover any port holes (for a clean look)? Or is that generally advised to avoid? Thanks again!
The grills do effect sound quality from diffraction and some HF loss but only to a minor degree. They can cover port holes provided there is airspace between the port and the grill fabric. If you put the material right up against the port you will loose quite a bit of bass output due to restriction. Though this also depends on the type of speaker, for subs with very high airflow from the ports it's not the best idea to cover them at all.