Symphony S4 Full Range Class D Amplifier The new & improved Symphony amplifiers are packed with even more power density than the highly renowned originals! The S4 is rated for a total of 880w of clean RMS output!Efficient design only requires the use of 4 gauge power and ground cables.New Custom tooled Symphony heatsink optimized for uncompromising heat dissipation while keeping form factor at an all time low.Built in 18db/Slope crossover network grants precise adjustment of your system's needs and features LPF/HPF & Bandpass and allowsthe user to control the frequency points up to 8khz!2ch/4ch selector switch (No RCA splitters will ever be needed)All Symphony models utilize heavy copper traces in the Korean built boards, as well as top quality components used throughout. Input signal transfers cleanly to the board via the Tiffany style RCA input jacks.S4 Rated Power output @ 13.8v (RMS):2ohm: 220w x44ohm: 140w x4Bridged 4ohm: 440w x2S4 Dimensions: 8.5"L x 7.6"W x 2.5"H80a to 100a fuse for the power input suggestedFree shipping in the continental USA.