RDL STM-1 Microphone Preamplifier

The STM-1 is a low-cost, high-quality miniature wall and surface mount microphone preamplifier from RDL, designed for use in commercial sound and broadcast applications. The compact size makes it ideal where a larger or heavier preamp cannot be used.

The high-performance circuit provides a fixed 50dB gain to bring any microphone-level signal up to the line-level range of nearly any line input. The STM-1 supply input is single ended and operates from 24 to 33VDC. Operation from 12VDC is possible with a 6dB reduction in headroom. For intercom applications, the input will operate directly from a speaker.