3-inch Studiofoam Wedges are suitable for rooms with higher SPLs (Sound Pressure Levels) or more low frequencies such as drum or voiceover booths. Twice as absorbent as 2" at 125Hz, 3" Studiofoam Wedges can even do many of the same things 4" can do (especially when used with LENRD or Venus Bass Traps) and can provide a well-controlled, more accurate sound in any size room, so if you step up from 2" to 3" you will benefit from the extra low-end sound absorption 3" acoustic Studiofoam Wedges offer.