RDL STPA18
ST-PA18

OUR PART #  STPA18


Radio Design Labs' ST-PA18 features a balanced line level input that may be connected unbalanced. The gain control range will accommodate standard unbalanced levels as well as professional balanced levels. The module bridges the input signal. LOOP OUT terminals permit a balanced input to be fed to additional amplifier modules making the ST-PA18 an ideal component in distributed audio system design.

NOTE: Radio Design Labs' PS-24KS 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-24KS power supply.

The LOOP OUT may also be used to feed a subwoofer amplifier (see RDL ST-CX2S Subwoofer Filter). The ST-PA18 output will drive an 8 ohm speaker or multiple speakers connected to present an 8 ohm load to the amplifier and it is capable of driving 4 O loads. A red COMP LED is provided to indicate the threshold of the integral compressor. Audio levels that could cause the amplified output to clip are compressed according to two dynamic time constants. Normal audio level signals remain unaffected by the compressor thereby preserving audio dynamics and preventing the compressor from increasing feedback potential when the amplifier is used for paging.

The compressor is designed to remain aurally transparent while maintaining clean, unclipped amplified audio for input overloads of up to 20 dB. The ST-PA18 produces average audio levels and audio clarity normally expected of amplifiers delivering much higher output power. The ST-PA18 operates from an external 24 VDC 1A power supply, sold separately. A POWER LED illuminates when the module is powered. The module provides thermal and output short-circuit protection.

Radio Design Labs ST-PA18 Features:

  • 18 Watts RMS Audio Power Amplifier
  • Output for 8 ohm Speaker
  • Maximized Audio Level at Full Power Output
  • Superior Audio Quality at High Output Levels
  • Line Level Balanced or Unbalanced Input
  • LOOP OUT to Feed Additional Amplifiers
  • Integral Audio Compressor to Control Clipping
  • High Overall Audio Operating Level
  • LED to Indicate Audio Compression

Radio Design Labs ST-PA18 Specifications:

  • Input: Line level (+4 dBu bal; -10 dBV unbal)
  • Input Impedance: 20 kohm balanced bridging; 10 kohm unbal
  • Gain Adjustment: Single turn
  • Minimum Input Levels: -16 dBu* balanced; -18 dBV* unbalanced
  • Maximum Input Levels: +25 dBu balanced; +22 dBV unbalanced
  • Frequency Response: 20 Hz to 20 kHz (+/- 2 dB)*
  • THD+N: < 1%*
    *Measured at compressor threshold level equaling 12 W RMS output power
  • Noise: < -75 dB (below 18 W RMS)
  • Compressor: Threshold 3 dB below rated output, automatic adjusting attack and release
  • CMRR: > 45 dB (50 Hz to 120 Hz)
  • Output Power: 18 W RMS into 8 O
  • Output Circuit: Class D
  • Ambient Operating Environment: 0° C to 30° C Max; 20° C Recommended
  • Indicators(2):
    • Red LED: LED indicates compressor activity
    • Green LED: PowerON
  • Power Requirement: 24 Vdc @ 1000 mA, Ground referenced
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Radio Design Labs' STR-19A Racking System holds up to 12 STICK-ONs in a 19" rack and only occupies two rack spaces.
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RDL PS24KS  24V @ 1000mA Power Supply

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Typical Performance: Input: 100 to 240 VAC Output: 24 Vdc, 1 A (UL, CSA) Dimensions: 1.80" x 3.51" x 1.55" (4.6  x 8.9 x 3.9 cm) Efficiency: ENERGY STAR Level IV
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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.
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RDL DRA-35S  Din Rail Adaptor for STICK-ON

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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 ...
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Two mounting brackets mounts a STICK-ON, TX, or Rack-Up module to a flat surface.
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RDL STR19B STR-19B

RDL STR19B STR-19B

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 ...
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Please call for availability.
RDL SR4 SR-4

RDL SR4 SR-4

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. ...
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Usually ships in 6-10 business days.
RDL SR10 SR-10

RDL SR10 SR-10

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 ...
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Usually ships in 4 business days.
RDL SR12A SR-12A

RDL SR12A SR-12A

Radio Design Labs' SR-12A chassis can be mounted in a rack or on a backboard to provide mounting of 12 STICK-ONs.
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Usually ships in 6-10 business days.
RDL SMK12 Smk 12 Mounting Strip for STICK-ON Units

RDL SMK12 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.
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Usually ships in 6-10 business days.
RDL DTB-RDL Dtb Rdl Detachable Terminal Block

RDL DTB-RDL Dtb Rdl Detachable Terminal Block

Use DTB's to quickly detach and reattach wiring harness to STICK-ON units.
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Usually ships in 4 business days.

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