The sE Electronics RF PRO is a portable acoustic treatment device which is ideal for recording in a home studio. With multi-layered technology it absorbs sound across all frequencies. The RF Pro consists of nine layers of sE's patented multi-layer technology, and is constructed by hand in sE's very own factory. Different materials are better at absorbing and diffusing particular portions of the frequency spectrum. Foam, for example, is great for highs, but does absolutely nothing for lows. On its own, foam will just make your tracks sound dull, causing you to EQ the highs back in, which adds noise to your recordings. The trick is to balance the absorption evenly across ALL frequencies, and that requires multiple layers of material.