Formula Sound AVC2

Description

The AVC2 fulfills the need to control fixed or installed sound systems as opposed to temporary or mobile systems. The reasons for installing this equipment would be to address:-

Health and Safety issues in colleges or training environments, or in professional working environments,
e.g. in recording or broadcast studios to control the monitoring system. (We have supplied units to several radio stations for this application.)

Noise pollution situations
e.g. entertainment venues which are located near residential property. This is by far the largest use of this product.

Main Features

• Automatic Volume Control
• Bar-Graph Level Meter
• Anti-Tamper Relay Fitted for System Security
• Optional Remote Warning Indicator Available

Product Features

• There is no reduction in the dynamic range of the system under normal operating conditions
• The AVC2 has no external controls for the operator to worry about which also means that tampering is minimised. A bar graph meter informs he operator how much level the unit is holding.
• An anti-tamper relay is fitted which can be connected to an external switch to improve system security.
• The unit has provision to connect to an external time switch (not supplied) to switch between two output levels.
• An external remote warning indicator may be connected to warn the operator that the operating level is 3dB away from the threshold at which the AVC2 will start to control level.

Product Specifications

• Max input level: +22dBu: clip indicates at +20dBu
• Input impedance: 20k balanced (electronically), 10k unbalanced.
• Noise: –90dBu 20Hz-20kHz 0dB attenuation
• Distortion (THD): <0.01%, 0dB output, 0dB attenuation. <0.015%, 0dB output, 12dB attenuation. <0.05%, 0db output 30dB attenuation
• Threshold ranges: –2 to +5dBu, or –8 to –14dBu
• Attenuator range: 3-30dB
• Power: 220–240V AC (cable supplied)
• Dimensions: 482(w) x 200(d) x 44(h) mm

The problem with sound systems is not the equipment, but the operators. We cannot take away the knobs and controls which they need to do their job. What we can do is control the maximum level at which the system will play irrespective of what they do. The AVC2 is an Automatic Volume Control unit and as the name suggests behaves just like someone leaning over the operator''s shoulder and turning the volume down each time he tries to turn it up above what is allowed.

The more the operator tries to increase the volume the more the AVC2 will decrease it, so the system will barely change in perceived volume level. Eventually the operator will run out of controls to turn up. If the AVC2 is driven to maximum the output level will be reduced by more than the increase in input level. The system will probably now sound distorted and generally not very nice but the volume will be at a lower than normal level. Turning down the volume will allow the system to return back to normal operating level. (Maturity, we are told, is knowing that you can turn a volume control down as well as up)

It should be noted that this unit is not a compressor and will not significantly change the dynamic range of the music. This is because it is fairly slow in its action and therefore has a response time of a few seconds depending on musical content. There are no user controls on the AVC2 to be tampered with, only a bar graph meter showing how much control the AVC2 is exercising.

The AVC2 works by controlling the signal level before it gets to the loudspeakers. As this signal level is directly proportional to the noise the loudspeakers produce we do not need a measuring microphone for the system to work.

This explains the AVC2 in basic simple terms. More detailed technical information is available in the brochure. Although the AVC2 will control any sound system and do so in a way that won''t embarrass or upset anyone it can only perform satisfactorily if it is installed and calibrated correctly in the venue. It is not practical to use the AVC2 in a mobile situation or where visiting artistes, bands, DJs, etc. bring their own equipment. The reasons are many, such as the problems of interfacing this equipment to visiting sound systems in the time available before a performance; where to connect it; having the correct connectors available; having the time to calibrate the equipment in the venue; having technical staff available to do the work