ONE PA/VA EN 54-16 EN 54-4

ONE is a complete PA system and voice evacuation, with EN 54-4 battery charger integrated in a single device.

It has an innovative Wall & Rack design that allows it to be mounted on both the wall and the rack, according to the needs of each project.

The ONE system is very easy to install and configure, without the need for external applications, and integrates perfectly with third-party technologies.

Who said small?

ONE stands out for its advantages

Minimalist and compact

The ONE design has been designed to fit like a glove and make optimal use of the available space in any installation, mural or rack.

International certificate

ONE is a certified system according to the international standard EN 54-16 (0370-CPR-3206) and has an integrated battery charger and housing also certified EN 54-4.

Easy installation

The installation, start-up and maintenance of a ONE system is very simple, saving a lot of time and costs.

Maximum functionality

With 2 class D amplifiers and up to 500 W of power, 6 independent audio outputs, DSP equalizer and 6x6 digital audio matrix.

Reliable first

Manufactured in Spain with maximum attention to all details, following strict quality standards and with the support of a large technical support team.

Adapts to any configuration

The ONE system is perfect for basic installations of small and medium format, with great flexibility when integrating with other systems.


Compact on the outside, big on the inside


+6 outputs/zones
Digital 6×6 audio matrix, expandable.

+2 class D amplifiers

With two configurations for 100/70 V lines up to 500 W. Backup amplifier included.

+EN 54-4 certified battery charger

EN 54-4 battery charger with 12 V 18 Ah battery.

+3 audio inputs

3 audio inputs (BGM or mic) + 1 mixed input. Noise gate and control activation.

+Up to 8 microphones

Paging station input up to 8 MPS-8Z multizone microphones or VAP-1 voice alarm panel.

+Pre-recorded messages

Dual message player for pre-recorded messages EVAC + ALERT. Phased evacuation. 10 minutes storage for pre-recorded messages.

+LCD display

Access control by LCD display.

+Wall&Rack design

Wall & Rack design, easy to install. Plug & Set mode for PA/VA EN 54.

+8+2 GPIO ports

8+2 GPIO ports (supervised for integration with Fire Alarm Control Panel).

+Attenuators control 

+4 pre-amp outputs

4 pre-amp outputs for external PA amplifiers connection.

+DSP equalizer

DSP: 3/7-band input/output parametric equalizer, loudness, LDA sound enhancer, independent volume control per each input and output master.

+Loudspeaker lines supervision

Line terminators without return for supervision.

+Failure detection and indication

Failure detection and indication in all emergency functions. USB backup/restore and emergency log.

+Made in Spain

Designed and made in Spain by LDA Audio Tech.

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Microphone ONE-PTT

EN 54-16 certified dynamic microphone with PA/VA functionality.

ONE-LOOP communication module

Expansion module to connect ONE units and perform a united system up to 60 zones.

Battery update and activation card EN54-4 certified for ONE-500.

12V and 17Ah lead-acid battery for LDA ONE-500.

Wall mounting kit for LDA ONE-500.

Fixed mounting for 19” rack.

Rack mounting kit in 3U 19″ rack cabinet for removable ONE-500.


High performance digital paging station with “all-call” button, busy line signal, auto-lock function and event button.

Keyboard expansion unit for the MPS-8Z microphone, it adds 8 extra programmable buttons.

High performance desktop microphone with lighting indicators and different operational modes.

Filtered load impedance to improve the accuracy of loudspeaker line measurement in 70/100 V lines.

Voice alarm panel that offers a remote and supervised control of the NEO’s VA features.

Keyboard expansion unit for the VAP-1 voice alarm panel, it adds 8 programmable buttons.

VAP-1EC Blank Block

Blank block for voice alarm panel VAP-1 that can be used both in rack and installed on the wall.

19″ and 4U cabinet with glass front door and lock, all blank panels and required accessories.

19″ and 6U cabinet with glass front door and lock, all blank panels and required accessories.

Red wall rack for VAP-1 EQ-242057

Wall cabinet for housing a VAP-1 microphone unit and a VAP-8K keyboard extension.

Multisource player RCD-21R

All-in-one multi-source audio player with USB and SD card.

AT Series Attenuators

Attenuators for high impedance public address lines of 70 or 100 V.

Suface mount back box for series AT attenuators

Box for surface mounting of AT series attenuators.

ONE Stand-alone unit system EN54
ONE System Expandable



ONE · PA/VA EN 54-16 EN 54-4 system


Certification EN 54-16 and EN 54-4


Discover all the features of ONE


Configuration, start-up and maintenance of ONE


All the available downloads for ONE products