Radio Design Labs STM-2
Adjustable Microphone to Line Preamplifier

OUR PART #  STM2


Radio Design Labs' STM-2 is a quality low-noise microphone preamplifier designed for use in commercial sound, broadcast, and recording. The STM-2 is very flexible, with gain adjustment from off to +65 dB, two balanced or unbalanced outputs, and available phantom supply input! Its ultra-low distortion and low-noise performance make it the best choice, even when larger preamps could be used! The single-ended supply input range is from 12 to 33 Vdc! Each output drives high or low impedance loads.

NOTE: Radio Design Labs' PS-24AS power supply is NOT included but is required in order to power this product.  Please see the "Accessories" tab or click here for more information on the PS-24AS power supply.

RDL STM-2 Features:

  • Low-Noise Mic Preamp
  • Adjustable Output Level
  • High or Low Impedance Mic Inputs
  • Mic Input to 2 Line Outputs
  • Two Balanced or Unbalanced Outputs
  • Phantom Capability
  • RF-Filtered Inputs

RDL STM-2 Specifications:

  • Input: 500 O balanced; 5 kO unbalanced
  • Phantom: 24 Vdc; IEC 61938: 2013, Filtered
  • Outputs (2): +4 dBu 150 O balanced; -10 dBv unbalanced
  • Frequency Response: 50 Hz to 30 kHz (± 1.5 dB)
  • Gain: Adjustable 35 to 65 dB
  • THD+N: < 0.05% (50 dB Gain)
  • CMRR: >50 dB (50 Hz to 20 kHz)
  • Residual Noise: < -70 dB (below +4 dBu 150 O source @ 50 dB gain)
  • Headroom:
    • > 20 dB (24 Vdc supply)
    • > 14 dB (12 Vdc supply)
  • Phantom Power Input: 24 to 33 Vdc @ 10 mA maximum
  • Power Requirement: GROUND-REFERENCED, 24 to 33 Vdc @ 25 mA
  • Ambient Operating Environment: 0°C to 55°C
  • Dimensions (HxWxD): 0.7" x 3" x 1.6" (1.7 x 7.6 x 3.9 cm)
  • Package Type: Cardboard Box
  • Package Dimensions: 2" x 2" x 4"
  • Shipping Weight: 0.195 lbs.
  • WEEE weight: 0.145 lbs.
  • Tariff code: 8518.40.2000
Radio Design Labs STR-19A Rackmount System for 12 Stick-On Units
Radio Design Labs STR-19A Rackmount System for 12 Stick-On Units
Radio Design Labs' STR-19A Racking System holds up to 12 STICK-ONs in a 19" rack and only occupies two rack spaces.
Radio Design Labs PS-24AS 24 VDC 500mA Switching Power Supply, North American Model
Radio Design Labs PS-24AS 24 VDC 500mA Switching Power Supply, North American Model
Radio Design Labs' PS-24AS is a 24 VDC/500 mA switching power supply with a North American AC plug. Compatible with various RDL products.Radio Design Labs PS-24AS Specifications: Input: 100 to 240 VAC Output: 24 Vdc, 500 mA (UL, ...
Radio Design Labs ST-RRB1 Mounting Bracket for STICK-ON Modules
Radio Design Labs ST-RRB1 Mounting Bracket for STICK-ON Modules
Radio Design Labs' ST-RRB1 mounting kit contains a bracket to attach a STICK-ON module to a rear rack rail or to any flat surface. The module slides into the holder and snaps into position. The module may easily be removed.
Radio Design Labs DRA-35S  Din Rail Adaptor for STICK-ON
Radio Design Labs DRA-35S Din Rail Adaptor for STICK-ON
The DRA-35S is a 35 mm DIN rail mounting bracket that provides positive mounting for any RDL STICK-ON® module. The oblique mounting angle of the DRA-35S allows an installer to mount several STICK-ON modules to a single DIN rail. Access to ...

Usually ships in 7-14 business days.
Need it sooner? Call us!
Radio Design Labs MB1-RDL Mounting Kit for STICK-ON, TX, or Rack-Up module
Radio Design Labs MB1-RDL Mounting Kit for STICK-ON, TX, or Rack-Up module
Two mounting brackets mounts a STICK-ON, TX, or Rack-Up module to a flat surface.
Radio Design Labs STR-19B Rackmount Kit for 10 Stick-On Units
Radio Design Labs STR-19B Rackmount Kit for 10 Stick-On Units
Radio Design Labs' STR-19B Racking System holds up to 10 STICK-ON unitss in a 19 inch rack and only occupies two rack spaces. The STR-19B holds STICK-ONs at an angle allowing for control adjustment from either the edge of a STICK-ON, or ...

Usually ships in 7-14 business days.
Need it sooner? Call us!
Radio Design Labs SR-4 Mounting Frame for Stick/TX
Radio Design Labs SR-4 Mounting Frame for Stick/TX
Radio Design Labs' SR-4 is a universal module chassis that can mount to a backboard, wall or nearly any other support. It provides mounting for 4 STICK-ON power amplifiers or 7 standard STICK-ON modules. TX ™ modules may also be mounted. ...

Usually ships in 7-14 business days.
Need it sooner? Call us!
Radio Design Labs SR-12A STICK-ON Series 19"W Mounting Rack for up to12 Modules
Radio Design Labs SR-12A STICK-ON Series 19"W Mounting Rack for up to12 Modules
Radio Design Labs' SR-12A chassis can be mounted in a rack or on a backboard to provide mounting of 12 STICK-ONs.

Usually ships in 7-14 business days.
Need it sooner? Call us!
Radio Design Labs SR-10 Stick-On Mounting Rack for 10 Units
Radio Design Labs SR-10 Stick-On Mounting Rack for 10 Units
Radio Design Labs' STR-10 Racking System holds up to 10 STICK-ON units.  It holds STICK-ONs at an angle allowing for control adjustment from either the edge of a STICK-ON, or the top (depending on where the adjustment is located on ...

Usually ships in 7-14 business days.
Need it sooner? Call us!
Radio Design Labs Smk 12 Mounting Strip for STICK-ON Units
Radio Design Labs Smk 12 Mounting Strip for STICK-ON Units
The SMK-12 allows removable surface (up to 6 units) or edge (typically 12, max. 16) mounting of STICK-ON units. They can be fastened to its surface using screws or adhesive foam pads.

Usually ships in 7-14 business days.
Need it sooner? Call us!
Radio Design Labs Dtb Rdl Detachable Terminal Block
Radio Design Labs Dtb Rdl Detachable Terminal Block
Use DTB's to quickly detach and reattach wiring harness to STICK-ON units.

Usually ships in 7-14 business days.
Need it sooner? Call us!

Click to download

Radio Design Labs STM-2
Adjustable Microphone to Line Preamplifier

OUR PART #  STM2

Product Information:

Radio Design Labs' STM-2 is a quality low-noise microphone preamplifier designed for use in commercial sound, broadcast, and recording. The STM-2 is very flexible, with gain adjustment from off to +65 dB, two balanced or unbalanced outputs, and available phantom supply input! Its ultra-low distortion and low-noise performance make it the best choice, even when larger preamps could be used! The single-ended supply input range is from 12 to 33 Vdc! Each output drives high or low impedance loads.

NOTE: Radio Design Labs' PS-24AS power supply is NOT included but is required in order to power this product.  Please see the "Accessories" tab or click here for more information on the PS-24AS power supply.

RDL STM-2 Features:

  • Low-Noise Mic Preamp
  • Adjustable Output Level
  • High or Low Impedance Mic Inputs
  • Mic Input to 2 Line Outputs
  • Two Balanced or Unbalanced Outputs
  • Phantom Capability
  • RF-Filtered Inputs

RDL STM-2 Specifications:

  • Input: 500 O balanced; 5 kO unbalanced
  • Phantom: 24 Vdc; IEC 61938: 2013, Filtered
  • Outputs (2): +4 dBu 150 O balanced; -10 dBv unbalanced
  • Frequency Response: 50 Hz to 30 kHz (± 1.5 dB)
  • Gain: Adjustable 35 to 65 dB
  • THD+N: < 0.05% (50 dB Gain)
  • CMRR: >50 dB (50 Hz to 20 kHz)
  • Residual Noise: < -70 dB (below +4 dBu 150 O source @ 50 dB gain)
  • Headroom:
    • > 20 dB (24 Vdc supply)
    • > 14 dB (12 Vdc supply)
  • Phantom Power Input: 24 to 33 Vdc @ 10 mA maximum
  • Power Requirement: GROUND-REFERENCED, 24 to 33 Vdc @ 25 mA
  • Ambient Operating Environment: 0°C to 55°C
  • Dimensions (HxWxD): 0.7" x 3" x 1.6" (1.7 x 7.6 x 3.9 cm)
  • Package Type: Cardboard Box
  • Package Dimensions: 2" x 2" x 4"
  • Shipping Weight: 0.195 lbs.
  • WEEE weight: 0.145 lbs.
  • Tariff code: 8518.40.2000
Radio Design Labs STR-19A Rackmount System for 12 Stick-On Units
Radio Design Labs STR-19A Rackmount System for 12 Stick-On Units
Radio Design Labs' STR-19A Racking System holds up to 12 STICK-ONs in a 19" rack and only occupies two rack spaces.
Radio Design Labs PS-24AS 24 VDC 500mA Switching Power Supply, North American Model
Radio Design Labs PS-24AS 24 VDC 500mA Switching Power Supply, North American Model
Radio Design Labs' PS-24AS is a 24 VDC/500 mA switching power supply with a North American AC plug. Compatible with various RDL products.Radio Design Labs PS-24AS Specifications: Input: 100 to 240 VAC Output: 24 Vdc, 500 mA (UL, ...
Radio Design Labs ST-RRB1 Mounting Bracket for STICK-ON Modules
Radio Design Labs ST-RRB1 Mounting Bracket for STICK-ON Modules
Radio Design Labs' ST-RRB1 mounting kit contains a bracket to attach a STICK-ON module to a rear rack rail or to any flat surface. The module slides into the holder and snaps into position. The module may easily be removed.
Radio Design Labs DRA-35S  Din Rail Adaptor for STICK-ON
Radio Design Labs DRA-35S Din Rail Adaptor for STICK-ON
The DRA-35S is a 35 mm DIN rail mounting bracket that provides positive mounting for any RDL STICK-ON® module. The oblique mounting angle of the DRA-35S allows an installer to mount several STICK-ON modules to a single DIN rail. Access to ...

Usually ships in 7-14 business days.
Need it sooner? Call us!
Radio Design Labs MB1-RDL Mounting Kit for STICK-ON, TX, or Rack-Up module
Radio Design Labs MB1-RDL Mounting Kit for STICK-ON, TX, or Rack-Up module
Two mounting brackets mounts a STICK-ON, TX, or Rack-Up module to a flat surface.
Radio Design Labs STR-19B Rackmount Kit for 10 Stick-On Units
Radio Design Labs STR-19B Rackmount Kit for 10 Stick-On Units
Radio Design Labs' STR-19B Racking System holds up to 10 STICK-ON unitss in a 19 inch rack and only occupies two rack spaces. The STR-19B holds STICK-ONs at an angle allowing for control adjustment from either the edge of a STICK-ON, or ...

Usually ships in 7-14 business days.
Need it sooner? Call us!
Radio Design Labs SR-4 Mounting Frame for Stick/TX
Radio Design Labs SR-4 Mounting Frame for Stick/TX
Radio Design Labs' SR-4 is a universal module chassis that can mount to a backboard, wall or nearly any other support. It provides mounting for 4 STICK-ON power amplifiers or 7 standard STICK-ON modules. TX ™ modules may also be mounted. ...

Usually ships in 7-14 business days.
Need it sooner? Call us!
Radio Design Labs SR-12A STICK-ON Series 19"W Mounting Rack for up to12 Modules
Radio Design Labs SR-12A STICK-ON Series 19"W Mounting Rack for up to12 Modules
Radio Design Labs' SR-12A chassis can be mounted in a rack or on a backboard to provide mounting of 12 STICK-ONs.

Usually ships in 7-14 business days.
Need it sooner? Call us!
Radio Design Labs SR-10 Stick-On Mounting Rack for 10 Units
Radio Design Labs SR-10 Stick-On Mounting Rack for 10 Units
Radio Design Labs' STR-10 Racking System holds up to 10 STICK-ON units.  It holds STICK-ONs at an angle allowing for control adjustment from either the edge of a STICK-ON, or the top (depending on where the adjustment is located on ...

Usually ships in 7-14 business days.
Need it sooner? Call us!
Radio Design Labs Smk 12 Mounting Strip for STICK-ON Units
Radio Design Labs Smk 12 Mounting Strip for STICK-ON Units
The SMK-12 allows removable surface (up to 6 units) or edge (typically 12, max. 16) mounting of STICK-ON units. They can be fastened to its surface using screws or adhesive foam pads.

Usually ships in 7-14 business days.
Need it sooner? Call us!
Radio Design Labs Dtb Rdl Detachable Terminal Block
Radio Design Labs Dtb Rdl Detachable Terminal Block
Use DTB's to quickly detach and reattach wiring harness to STICK-ON units.

Usually ships in 7-14 business days.
Need it sooner? Call us!

Click to download

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