Overview
The STM-3 is a quality low-noise microphone preamplifier designed for use in surveillance, commercial sound, broadcast, and recording where higher than normal gain is required. The STM-3 is very flexible, with gain adjustment from 45 to 75 dB, two balanced or unbalanced outputs, and available phantom supply input. Its low-distortion and low-noise performance make it the best choice, even when larger preamps could be used. The STM 3 supply input is single ended and operates from 24 Vdc. Operation from 12 Vdc is possible with a 6 dB reduction in headroom. Each output drives high or low impedance loads.
Features:
- Low-Noise, High-Gain, Mic Preamp
- Adjustable Output Levels
- High or Low Impedance Mic Inputs
- Mic Input to Line Outputs
- Two Balanced or Unbalanced Outputs
- Phantom Capability
- RF-Filtered Inputs
Specifications
Input:
500 Ω balanced; 5 kΩ unbalanced
Phantom:
24 Vdc; IEC 61938: 2013, Filtered
Output (2):
+4 dBu 150 Ω balanced; -10 dBV unbalanced
Frequency Response:
50 Hz to 30 kHz (± 1.5 dB)
Gain:
Adjustable 45 to 75 dB
THD+N:
< 0.05% (50 dB gain)
CMRR:
> 50 dB (50 Hz to 20 kHz)
Residual Noise:
< -70 dB (below +4 dBu, 150 Ω source)
Headroom:
> 20 dB (24 Vdc supply); 14 dB (12 Vdc supply)
Phantom Power Input:
24 Vdc @ 10 mA maximum
Ambient Operating Environment:
0° C to 55° C
Power Requirement:
GROUND-REFERENCED, 24 Vdc @ 25 mA
Dimensions:
Height: 0.7 in. (1.7 cm); Width: 3 in. (7.6 cm); Depth 1.6 in. (3.9 cm)
Package Type:
Cardboard Box
Package Dimensions:
2 x 2 x 4 in.
Shipping Weight:
0.195 lbs.
WEEE weight:
0.145 lbs.
Tariff code:
8543.70.9960
RDL Three-Year Limited Warranty
Installation of these products by the Purchaser shall constitute Purchaser’s acknowledgement and acceptance of the terms and
conditions for sale and of this warranty, and shall constitute the Purchaser’s determination of the suitability of this product for the
Purchaser’s intended application. Radio Design Labs, Inc., also referred to as RDL®, warrants to the Purchaser that products
manufactured by RDL are free from defects in material and workmanship. This warranty applies to the period of three years from the date
of shipment, except for component parts or products purchased from other sources and supplied by RDL. Such component parts or
products bear only the warranty of the manufacturer thereof in effect at the time of shipment to the Purchaser. RDL will, without charge,
and after written notice has been received and acknowledged by RDL, repair an RDL product if proved to be defective according to the
usage of the trade, when such equipment is received by RDL at the location it designates with shipment costs prepaid by the Purchaser.
RDL shall not be liable for any expense whether for repairs, replacements, material, service, or otherwise, incurred by the Purchaser or
modifications made by the Purchaser to the product. No equipment shall be deemed defective if it shall fail to operate in a normal or
proper manner due to exposure to excessive moisture in the atmosphere, excessive temperature extremes, improper environmental
cleanliness, or any other environment not consistent with the principles of good engineering practice. In no event shall RDL have any
liability for consequential damage or expense directly or indirectly arising from the use of the products, or any inability to use it either
separately or in combination with other equipment or materials, or from any other cause, whether used in accordance with instructions or
not. This warranty is void if equipment is altered in any way by other than RDL. RDL products are NOT intended for use in life support
appliances, devices, or systems. Use of RDL products in such applications is done solely at the liability of the reseller/installer and/or end
user. RDL reserves the right to change design parameters and specifications at any time without notice. The performance measurements
reflect the products at the time of printing. This warranty is in lieu of all others, either expressed or implied. No representative is authorized
to assume for RDL any other liability in connection with RDL products.
