The TC Electronic RH450 amp can run any combination of up to 3 units. This bass amp head's features include an input that accepts passive or active instruments, 4 semi-parametric tone controls with light rings around each knob that make your settings visible even on dark stages, and with tone centers that can be adjusted. Other features include an integrated tuner that is precise and extremely easy to use. 3 user-memory locations let you store your favorite setups. A TubeTone circuit affects both the preamp and the output for realistic tube-amp character. SpectraComp technology provides multi-band compression that is even across all strings. I/O is comprehensive and includes an AES/EBU connection. Presets, Mute, and Tuner can be selected remotely with the RC4 floor controller sold separately..