General
Model	VLA-120C
Output power	120 W RMS
Maximum output power	180 W
Frequency response	50 Hz – 18.000 Hz (-3 dB)
MIC noise level	>70 dB
LINE noise level	>80 dB
Total harmonic distortion	<1 % at 1 kHz
Inputs MIC/LINE 1–3	Symmetrical -50 dBu / -10 dBu, 5 kΩ
LINE inputs 4–5	unsymm. -10 dBu, 15 kΩ
TEL paging input	electrical symmetrical, -10 dBu, 10 kΩ
Remote control MIC input	asymmetrical, -50 dBu, 5 kΩ
AMP-IN input	0 dBu, 10 kΩ, unsymmetrical
REC-OUT output	0 dBu, 3 kΩ, unsymmetrical
PRE-OUT output	0 dBu, 100 Ω, unsymmetrical
Speaker outputs	100 V / 70 V / 4 Ω
Loudness control	In steps (100 V – 8.9 V) on 5 zones + All-Call
Gain and priority control	On MIC 1–3
Height and depth adjustment	On inputs 1–5
Phantom power	Switchable
Gong	2- or 4-tone, front-adjustable
Siren	constant or rising-falling, adjustable from front
TEL-Paging	With priority, adjustable
Current supply	230 V AC / 24 V DC (emergency power)
Power consumption	350 W
Type of fuse	1/8–0.8 A, Rated: 1.8 A
Slot for media module

The VLA-120C from RCS Audio-Systems is a professional amplifier and control unit for voice and paging systems. It serves as a central unit in sound systems requiring targeted control of up to five speaker circuits as well as a central All-Call mode, in which all zones are activated simultaneously. The unit is designed for use in schools, public institutions, industrial and event areas, where flexible and reliable communication is required. Each of the five speaker lines can be individually switched and volume-controlled in steps, enabling precise zoning.

Applications

The VLA-120C is suitable for applications requiring central control of multiple sound zones. It is commonly used in schools, hospitals, administrative buildings, or industrial production facilities, where targeted announcements, alarms, or information transmissions must be delivered across different areas. The ability to activate an All-Call makes it particularly suitable for emergency situations or general announcements. Compatibility with digital speaking stations such as the VLM-105 and VLM-205 enables remote control of speaker circuits, allowing the system to be operated from remote locations.

Functions and Equipment in Detail

The device features three MIC/LINE combo inputs equipped with switchable phantom power. These inputs support both microphones and line signals and offer gain and priority control to manage signal quality and input priority. Two additional LINE inputs expand connection options. A TEL-Paging input with priority function allows integration with telephone systems, enabling external calls to be directly connected to the sound system. The remote MIC socket allows connection of external microphones via an unbalanced cable.

Technology Explained Simply

The amplifier delivers an output power of 120 W RMS (up to 180 W maximum) and covers a frequency range of 50 Hz to 18,000 Hz, ensuring clear voice reproduction and sufficient audio quality. The total harmonic distortion is less than 1 % at 1 kHz, indicating high signal purity. The speaker outputs support voltage types 100 V, 70 V, and 4 Ω, with output voltage adjustable in steps from 100 V down to 8.9 V across five zones and an All-Call mode. This allows flexible adaptation to different speaker systems. The inputs are equipped with various impedances and levels to support a wide range of signal sources. The REC-OUT and PRE-OUT outputs provide connection options for recording devices or additional amplifiers.

Compatibility and Accessories

The VLA-120C is specifically designed for use with VARIO-LINE speaking stations VLM-100A, VLM-105, and VLM-205. The VLM-105 enables digital remote control of speaker circuits, while the VLM-205 additionally supports control of the Digital Text Module DM-10. Compatible digital microphone speaking stations for remote control of 5-speaker lines and All-Call are also available. A slot for a media module allows integration of CD players or other media sources. Power supply is via 230 V AC, with support for 24 V DC backup power to ensure functionality during power outages.

Mounting and Installation

The amplifier is housed in a 3-HE enclosure with dimensions 483 x 133 x 352 mm. It is designed for installation in standard 19-inch racks. Installation requires connecting the speaker circuits to the corresponding outputs, connecting inputs to microphones, line sources, or telephone systems, and providing power supply. Operation is performed via the front panel, where volume control, Gong and siren settings, and priority functions are adjusted. An automatic DC fan provides cooling, with fan speed regulated according to load.

Operational Advantages

The VLA-120C offers high operational reliability through integrated protection circuits against overload, overheating, and overcurrent. The adjustable Gong and siren functions allow generation of warning or signal tones, which can be configured as 2- or 4-tone Gong or as constant or rising/falling siren, depending on requirements. The TEL-Paging function with priority ensures that important messages can be transmitted even when other signals are active. The combination of flexible inputs, central control, and backup power capability makes the amplifier a robust solution for professional sound systems.

Scope of Delivery

The scope of delivery includes the VLA-120C amplifier, a power cable, and the operating instructions.