Class D Tech series  

Our first three loop drivers in the Class D Tech Series, Univox SLS-1,3 and 5, are the most efficient professional loop drivers for phased array systems available. They are substantially smaller and lighter than its predecessors. Their multiple class D stages makes them perfectly adapted to the requirements of modern phased array loop systems. With electronic transformers, efficient class D stage and silent fan free operation, they deliver unsurpassed high audio quality. The advanced and adaptive real time current and temperature protection makes SLS-series virtually indestructible with any load or short-circuit.



For small rooms


For medium sized rooms


For large rooms and auditoriums


The Univox Super Loop System Class D Tech series is based on groundbreaking, fully complementary, multiple class D stages. The high efficiency design has resulted in a series of loop drivers considerably smaller and lighter than their predecessors, with enhanced output power optimized for modern Super Loop (phased array) system design.  The combination of Univox technology, electronic transformers and silent fan free operation delivers unsurpassed loop drivers with a long product life.

Great sound

SLS Class D Tech loop drivers produces an amazingly clear sound and are also equipped with a low frequency masking filter for voice enhancement.


Smaller and lighter

The units are only 1U high. Weight is reduced by using significantly less copper and other metals than other loop drivers.

No fans needed

The electronic transformer gives 93% efficiency, compared to conventional transformers where the waste is 8-9 times higher. No internal fans are needed as there is no power leakage. Cooling is due to efficient design. This also prevents dust accumulation and noise, and it prolongs the products life length.

Environmentally friendly

The reduced use of copper together with the highly efficient and energy saving design, leaves a much smaller carbon footprint than its competitors. The SLS Class D Tech and the PLS-X series are the most environmentally friendly loop amplifiers in the world.

The self-diagnostic system

The self-diagnostics will indicate which systems are operational and which are not. The built-in signal generator can be used to set the output level if a different signal source is not available.

Enhanced metal loss compensation

Since different types of metals and their distances to the loop cable effect the sound, different types of compensation might be needed. The Class D Tech series is equipped with a unique Parametric MLC (Metal Loss Correction) to fine tune for the effects of metal loss.

Dual Action AGC

Univox was the first to include Dual Action AGC (Automatic Gain Control). When sudden and sharp sounds are suppressed, the Dual Action AGC lets the sound return immediately.

Butterworth low pass filter

The Class D Tech amplifiers are equipped with a Butterworth 24dB/octave low pass filter for effective noise-blocking between equipment.

Voice alarm system

The voice alarm system input overrides all other input signals and the 100 V input makes it possible to connect voice alarms from 100 V speakers directly to the amplifier.

Front control panel

All controls are placed on the front panel, which makes the driver easy to adjust, also when mounted in a rack.