The HDL 20-A is powered by a 1400W peak power digital amplifier, split 200W for the HF and 500W for the LF. A new generation DSP handles all the processing within the cabinet and allows adjustment of Cluster size and HF projection. The DSP also includes presets for indoor/outdoor usage and highly curved arrays. All these setting are accessed by the buttons on the rear of the cabinets.

The easy to access controls on the back of the speaker allow a number of simple optimisations to be carried out at the flick of a switch: two possible HF settings, four possible cluster configurations; a special EQ setting for high curved configurations and an Indoor Correction EQ.



MAIN XLR INPUT (BAL/UNBAL). The system accept female XLR input connectors and line level signals from a mixing console or other signal source.

LINK XLR OUTPUT. The output XLR male connector provides a loop trough for speakers daisy chaining.


Volume knob

Controls the volume of the power amplifier. The control ranges from - (maximum attenuation) to the MAX level (maximum output).


Status indicators

POWER INDICATOR. Power on indicator. When the power cord is connected and the power switch is turned on this indicator lights green.

SIGNAL INDICATOR. The signal indicator lights green if there is signal present on the main XLR input.

LIMITER INDICATOR. The amplifier has a built in limiter circuit to prevent clipping of the amplifiers or overdriving the transducers. When the peak clipping circuit is active the LED blinks orange. It is okay if the limit LED blinks occasionally. If the LED blinks frequently or lights continuously, turn down the signal level. The amplifier has a built in RMS limiter. If the RMS limiter is active the LED lights red. The RMS limiter has the purpose to prevent damages the transducers. The speaker shall never be used with the limit indicator red, continuous operation with the RMS protection active can cause damages to the speaker.

link and active leds

HF Switch

HF. The switch gives the possibility to set high frequencies correction depending on target distance (air absorption correction):

- NEAR (used for pole mount applications or near field)
- FAR (for farthest field).

link and active leds

Cluster Switch

The combination of the 2 switches gives 4 possibilities of mid low frequencies correction depending on cluster size.

- 2-3 modules (used for pole mount applications ground stacking)
- 4-6 modules (small flown systems)
- 7-9 modules (medium flown systems)
- 10-16 modules (maximum flown configuration).

link and active leds


The switch gives the extra possibility to boost mid frequencies depending on a high curving cluster configuration of few pieces.
- OFF (not active correction)
- ON (for high curving arrays of few pieces HDL20A).

link and active leds


The switch gives the extra possibility to set low frequencies correction depending on a indoor/outdoor use, in order to compensate room reverberation on lows.
- OFF (not active correction)
- ON (correction for reverberant indoor rooms).

link and active leds


RCF D LINE uses a POWERCON locking 3-pole AC mains. Always use the specific power cord provided in the package.

Use this receptacle to link one or more units. Always make sure that the maximum current requirement does not exceed the maximum admitted POWERCON current. In case of doubt call the closest RCF SERVICE CENTRE.

The power switch turns the AC power ON and OFF. Make sure that the VOLUME is set to - when you turn on the speaker.


In order to assist with the set up procedures for the HDL 20-A line array system, RCF has developed a complete prediction software package.

The software enables a complete two dimensional simulation of the behaviour of the HDL 20-A modules and also suggest the correct subwoofer combination.

The system curvature angles and the sound projection data are computed with maximum sound pressure levels for the given design.

The software will allow simulations up to a maximum of sixteen HDL 20-A systems.

The rigging menu provides data for weight, centre of gravity and length of the array configuration. Rigging points and rigging hardware configurations are also computed.