LL2C-4 CHANNEL OPTICAL AUDIO LIMITER – SOUND LIMITER FOR PREMISES

Price range: €971.95 through €1,294.02 IVA esclusa

LL2C-4 is a professional 4-channel optical audio limiter designed to control sound levels while preserving the highest audio signal quality.

Thanks to its fully analog circuitry and the control system based on a resistive optocoupler, the limiter provides smooth, progressive and almost imperceptible limiting, preserving the natural character of the audio program.

Unlike many traditional limiters based on VCA or digital processing, LL2C-4 uses a fully analog signal control system, ensuring a more musical and transparent response even when the limiter is active.

The modern electronic design, the use of selected low-noise components, and the careful quality control of the assembly process provide the LL2C-4 limiter with high reliability, stability and excellent audio performance, making it suitable for professional applications where multiple audio channels must be managed independently.

Description

The LL2C-4 audio limiter has been designed to provide high audio quality, operational safety and long-term stability of the settings, preventing any tampering after calibration.

The device features four independent audio channels, each with dedicated adjustments for:

  • input level

  • output level

  • limiting threshold

All adjustments are located inside the unit and are performed via internal trimmers, preventing accidental or intentional changes after installation.

All audio connections through connectors are also made inside the unit, increasing installation security and preventing unauthorized modifications or bypass of the limiter.

If the unit is switched off using the power switch located on the rear panel, the audio signal is completely interrupted, ensuring that no bypass of the limiter is possible.

The level control is achieved through an analog resistive optocoupler, without the use of VCA circuits.
This technical solution provides a more natural, progressive and musical limiting behavior, minimizing audible artifacts in the audio signal.

Installed in a standard 19″ rack enclosure, the LL2C-4 limiter is particularly suitable for audio systems where it is necessary to control multiple audio lines or zones independently while maintaining excellent sound quality.

Its smooth and progressive limiting response makes it ideal both for protecting audio systems and for sound level limitation in venues subject to noise regulations.

AVAILABLE VERSIONS

The LL2C-4 optical audio limiter is available in several configurations to meet different installation and sound level management requirements.

All versions share the same analog optical limiting circuit of the LL2C-4 base model and maintain the same professional audio quality, while differing in the way the limiting thresholds are managed.

Version 1 – LL2C-4 Standard (base model)

This is the standard version of the LL2C-4 audio limiter.

The unit features one limiting threshold per channel, adjustable via internal trimmers during system installation and calibration.

Input level, output level and threshold adjustments are located inside the unit to prevent tampering.

This configuration is ideal for installations where a fixed maximum sound level is required on four independent audio channels.

Version 2 – LL2C-4 with key-controlled threshold selection

This version allows the configuration of three different limiting thresholds for each channel.

The thresholds can be selected through a mechanical key switch located on the front panel, allowing the venue manager to choose between different pre-configured sound levels set by the installer.

This solution is particularly useful where it is necessary to manage:

  • daytime sound level

  • nighttime sound level

  • temporary higher level for authorized acoustic exemptions

The three thresholds are calibrated during system setup and can then be selected using the front panel key switch.

Version 3 – LL2C-4 with web controller management

This version includes a web-based controller with Wi-Fi access, allowing remote configuration and management of the limiting levels.

The system allows:

  • automatic management of day and night sound levels

  • configuration of temporary exemptions

  • scheduling of permitted levels using a web calendar

  • generation of a history log of all changes and operations

Two user profiles are available:

Administrator profile
managed by the installer, with full configuration and programming access.

User profile
intended for the venue manager, allowing data viewing and authorized level control.

This solution is particularly suitable for installations requiring automated sound level management and traceability of adjustments.

Version 4 – LL2C-4 with web controller and key switch

This version combines the web controller management with the mechanical key switch on the front panel.

The limiter can therefore be managed:

  • via web programming

  • or via manual key selection

providing maximum flexibility in installations where both remote management and local manual control are required.

 

  • four-channel audio limiter

  • four audio inputs and four outputs

  • balanced inputs and outputs

  • connections in via p.5

  • connections out via XLR 

  • audio connections made inside the unit

  • input, output and threshold adjustment via internal trimmers

  • level control using analog resistive optocoupler

  • no VCA circuits

  • circuitry using low-noise operational amplifiers

  • independent clipping and limiting indicators for each channel

  • frequency response (-3 dB): 20 Hz – 20 kHz

  • internal connections and adjustments

  • 19″ rack enclosure

Dimensions (W × D × H):
48 × 36.5 × 3.9 cm

Weight:
approx. 3.5 kg

Additional information

Weight 5 kg
Dimensions 65 × 50 × 25 cm
tipologia

LL2C Standard, LL2C Key Control, LL2C Web Control, LL2C Web + Key Control

The LL2C-4 audio limiter can be used in all installations where it is necessary to control sound levels on multiple audio channels while maintaining a warm, natural and well-defined sound.

Thanks to its analog optical limiting technology, the device reduces signal levels in a transparent and progressive way, avoiding sudden and unpleasant volume changes.

It is particularly suitable for:

  • sound level limitation in public venues subject to noise regulations

  • protection and safeguarding of audio systems

  • professional installations with multiple audio zones or independent lines

  • audio systems for bars, restaurants, clubs, event venues and public spaces

  • applications where it is necessary to control several channels while maintaining high audio quality

The analog optical limiting system ensures natural sound reproduction even during frequent limiter intervention.