Rivera RockCrusher Power Attenuator The RockCrusher is invaluable & unbeatably versatile because you can place it between your amp & speaker cab as a power attenuator, or use it in place of your speaker cabinet as a load box while sending its balanced XLR or unbalanced  line out to another amp as a slave, or even send its output to a mixer for recording or live performance. In addition to providing superior tone, impedance matching is critical for your tube amp's health & longevity. Rivera gave the RockCrusher an 8/16-ohm selector switch so you can use either value to accurately match your cabinets & amplifiers. Tthe RockCrusher is easy to use both on-stage & in the studio. For bypass on the fly, which lets you use the amp with a speaker cabinet when full output level is desired, Rivera included a front-panel full bypass switch that removes the load entirely. When low speaker volume is desired, there is a Studio position of the Attenuator Level Selector that enables the Studio Level control to adjust from low to quiet output--perfect for home, project, & studio recording. Balanced XLR & unbalanced " phone jacks with a convenient front-panel level control allow interfacing with practically any audio equipment. Two Speaker jacks allow easy connection with up to two speaker enclosures. Bullet-proof construction, a standard feature of Rivera equipment, is also engineered into the Rock Crusher: Within the 16-gauge welded steel chassis of the RockCrusher, heavy-duty & rugged industrial-grade components are used throughout & designed to give you years of reliable, cool-running service. In addition, both sides of the RockCrusher chassis facilitate mounting rack ears or other brackets for professional road case installation.