The STM-1 is a low-cost quality microphone preamplifier 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 50 dB gain to bring any mic-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 Vdc. Operation from 12 Vdc is possible with a 6 dB reduction in headroom. For intercom applications, the input will operate directly from a speaker.
RDL STM-1 Features
- High or low impedance input mic preamp
- Fixed 50 dB gain for consistency
- Balanced or unbalanced output
- Phantom capability
- RF-filtered inputs and outputs
- Excellent performance
- STICK-ON® convenience
- STM-1 microphone preamplifier1
- Input500 Ω balanced; 5 kΩ unbalanced
- Phantom24 Vdc; IEC 61938: 2013, Filtered
- Outputs (2)+4 dBu 150 Ω balanced; -10 dBv unbalanced
- Frequency Response50 Hz to 30 kHz (± 1.5 dB)
- Gain50dB nominal
- THD+N<0.05%
- CMRR>50 dB (50 Hz to 20 kHz)
- Residual Noise< -70 dB (below +4 dBu; 150 Ω source @ 50 dB gain)
- Headroom> 20 dB (24 Vdc supply); > 14 dB (12 Vdc supply)
- Phantom Power Input24 Vdc @ 10 mA max.
- Power RequirementGROUND-REFERENCED, 24 Vdc @ 25 mA