The Keeley Seafoam Plus Chorus expands on the lush, organic tone of the original with reconceived circuitry and two new modes for an even wider swath of functionality. Starting off with the Seafoam mode, you get big, warm BBD vintage-style chorus that fills a room with ease. Taking it even further, the Plus offers three-way switching with new Dual Chorus and ADT modes perfect not only for guitar, but bass and keys as well.