sr555We have 1 SRS Labs SR555 manual available for free PDF download: Operation Manual . SRS Labs SR555 Operation Manual (10 pages) Current Preamplifier. Brand: SRS Labs | Category:The SR555 is a low-noise, hh-bandwidth, fixed-gain current (trans-impedance) amplifier desned to work with SRS lockin amplifiers. Current amplifiers provide gain close to the experimental detector, allowing the user to minimize input