Radio Design Labs ST-CL2
Compressor/Limiter

OUR PART #  STCL2


Radio Design Labs' ST-CL2 is a high performance compressor/limiter designed to maintain a constant average output level and effective peak control over a wide range of input levels. The input and output are line level and each may be wired balanced or unbalanced. Trimmers provide adjustment for all usual professional and consumer audio input and output levels. Internal detectors feed three timing circuits. The threshold level and slope of each timing circuit are incremented to respond sequentially to signals of varying amplitude and energy levels.

The ST-CL2 features a soft-knee compression threshold and compression ratio which automatically adjust to the program material. Two LED indicators cover the incremental ranges of compression, making setting of the input level quick and easy. Two ST-CL2s may be strapped together for stereo operation by connecting the coupling terminals between the two modules.

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.

Radio Design Labs ST-CL2 Features:

  • Positive Audio Level Protection
  • Smooth Inaudible Gain Reduction
  • Tight Audio Peak Control
  • Very Low Noise Compressor
  • Multi Stage Incremental Gain Reduction
  • Fully Automatic Operation
  • Superb Performance with Minimal Setup
  • RDL® SupplyFlex™ Power Input Configuration

Radio Design Labs ST-CL2 Specifications:

  • Input:  10 kOhm Balanced (may be connected unbalanced)
  • Input Signal Range:  -10 to +4 dBu, adjustable (for 6 dB gainr reduction); +22 dBu maximum
  • Output:  150 Ohm Balanced (may be connected unbalanced)
  • Output Signal Range:  OFF to +8 dBu, adjustable
  • Frequency Response:  10 Hz to 20 kHz (+/- 0.2 dB) over full compression range
  • Noise below +4 dBu output:  < -78 dB (unweighted; +4 dBu input/output)
  • Total Harmonic Distortion:
    • < 0.05% @ 1 kHz below compression threshold
    • < 0.1% @ 1 kHz with 3 dB gain reduction
    • < 0.15% @ 1 kHz with 6 dBgain reduction
  • CMRR:  > 60dB (50 to 100 Hz)
  • AttackTime:
    • Averaging Compressor:  500 ms (+4 dBu input)
    • Fast Compression:  <10 ms (+20 dBu input)
    • Peak Limiting:  Instantaneous
  • Release Time:  Automatically adjusting up to 500 ms
  • Compression Ratio:  Automatically adjusting 1.5:1 to 10:1
  • Peak Limiter:  INF:1
  • Interconnection:  Stereo COUPLE interconnection provided
  • Indicators(2):
    • Yellow LED for NORMAL Compression
    • Red LED for HEAVY Compression
  • Power Requirement:  24 to 33 Vdc @ 50 mA,SupplyFlex
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.
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 ...
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, ...

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

Usually ships in 7-14 business days.
Need it sooner? Call us!
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 ST-CL2
Compressor/Limiter

OUR PART #  STCL2

Product Information:

Radio Design Labs' ST-CL2 is a high performance compressor/limiter designed to maintain a constant average output level and effective peak control over a wide range of input levels. The input and output are line level and each may be wired balanced or unbalanced. Trimmers provide adjustment for all usual professional and consumer audio input and output levels. Internal detectors feed three timing circuits. The threshold level and slope of each timing circuit are incremented to respond sequentially to signals of varying amplitude and energy levels.

The ST-CL2 features a soft-knee compression threshold and compression ratio which automatically adjust to the program material. Two LED indicators cover the incremental ranges of compression, making setting of the input level quick and easy. Two ST-CL2s may be strapped together for stereo operation by connecting the coupling terminals between the two modules.

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.

Radio Design Labs ST-CL2 Features:

  • Positive Audio Level Protection
  • Smooth Inaudible Gain Reduction
  • Tight Audio Peak Control
  • Very Low Noise Compressor
  • Multi Stage Incremental Gain Reduction
  • Fully Automatic Operation
  • Superb Performance with Minimal Setup
  • RDL® SupplyFlex™ Power Input Configuration

Radio Design Labs ST-CL2 Specifications:

  • Input:  10 kOhm Balanced (may be connected unbalanced)
  • Input Signal Range:  -10 to +4 dBu, adjustable (for 6 dB gainr reduction); +22 dBu maximum
  • Output:  150 Ohm Balanced (may be connected unbalanced)
  • Output Signal Range:  OFF to +8 dBu, adjustable
  • Frequency Response:  10 Hz to 20 kHz (+/- 0.2 dB) over full compression range
  • Noise below +4 dBu output:  < -78 dB (unweighted; +4 dBu input/output)
  • Total Harmonic Distortion:
    • < 0.05% @ 1 kHz below compression threshold
    • < 0.1% @ 1 kHz with 3 dB gain reduction
    • < 0.15% @ 1 kHz with 6 dBgain reduction
  • CMRR:  > 60dB (50 to 100 Hz)
  • AttackTime:
    • Averaging Compressor:  500 ms (+4 dBu input)
    • Fast Compression:  <10 ms (+20 dBu input)
    • Peak Limiting:  Instantaneous
  • Release Time:  Automatically adjusting up to 500 ms
  • Compression Ratio:  Automatically adjusting 1.5:1 to 10:1
  • Peak Limiter:  INF:1
  • Interconnection:  Stereo COUPLE interconnection provided
  • Indicators(2):
    • Yellow LED for NORMAL Compression
    • Red LED for HEAVY Compression
  • Power Requirement:  24 to 33 Vdc @ 50 mA,SupplyFlex
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.
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 ...
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, ...

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

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