Avalon Acoustics Sentinel Manuel D’Utilisation

6 Subwoofer Amplifier

Design Principle

The Sentinel subwoofer amplifier provides essential support for the lowest

octaves of the musical spectrum. As a fundamental component of the

Sentinel Reference System, the subwoofer amplifier has been specifically

designed to match the superlative speed and coherence of the Sentinel's

upper frequency response.

The 2400 watt subwoofer amplifier is a push-pull bridged design with fully

balanced circuitry. The amplifier utilizes a massive (2 KVA) toroidal transformer

and a storage capacity totaling over 70000 uF, with 10 high voltage/current

Bi-Polar output devices per channel and discrete high voltage/current

voltage regulation. The amplifier has a built-in electronic crossover that is

tuned specifically to the subwoofer driver array and box alignment. The result

is full-bandwidth low frequency output that has perfect phase coherence

down to 16 Hz.

Room Compensation

Loudspeaker positioning within a room dramatically influences sound

reproduction quality. In particular, the distances to the room boundaries

define a complex system of wave nodes and antinodes that can play havoc

with low frequency response and phase characteristics. For example, the

reflection from each room boundary (floor, side walls, front and rear walls,

and ceiling) creates antinodes when the sound wavelength is about four

times the distance to that boundary. The overall effect of these reflections is

acoustic room loading, more commonly known as "room boom."

The Sentinel subwoofer amplifier has a sophisticated electronic network that

allows for in-room tuning and adjustment that can compensate for this

loading effect. We strongly recommend the application of room treatment

(See Section 7, Maximizing Performance) before attempting any

compensations using the subwoofer amplifier. Once your system and room

have been properly set-up and treated, the following procedure can assist

you in fine-tuning your system.