The silver LA4 Rackmount Line Amplifier with Remote Control from Benchmark is a line-level preamplifier designed to sit between a reference-quality D/A converter and a reference-quality power amplifier. It offers relay gain control, relay input selection, and relay muting, and incorporates premium gold-contact relays. The gain control has 256 steps in 0.5 dB increments. Relay closures are precisely timed to deliver smooth volume changes. The LA4 incorporates a total of 40 precision relays and two independent 256-step attenuators, one for the left channel and one for the right channel.
The rear-panel I/O includes two balanced stereo XLR inputs, two unbalanced stereo RCA inputs, XLR and RCA stereo outputs, and a mono XLR output. Volume adjustments are executed via the 256-step balanced relay gain control, which uses increments of 0.5 dB. The integrated touchscreen allows convenient access to common functions such as input selection, dim, mute, and more.