Audio Note AZ-3 Owners manual

Music’s Finest Conductor

The Audio Note Absolute Zero AZ-Three Loudspeaker.

INTRODUCTION.

First of all thank you for buying an Audio Note product, I hope that it will reward you
with many years of good quality music and reliable service.

As a company our main aim is to design and manufacture equipment which gives you
the maximum sonic performance for the price and to do this we use many
unconventional solutions and the AZ-Three speaker is no exception to this, so it is
important that you read this brief manual carefully, in order for you to get the best
performance and sound from your new speakers.

The AZ-Three is designed to be used without a front cover or grill, and is therefore not
supplied with one. A cover can be easily made from transparent foam and four dots of
Velcro!

As with all Audio Note speakers, no corners have been cut in terms of component and
driver quality despite the modest price of the AZ-Three, the well tried and tested AN-E
tweeter and woofer feature in the two-way line-up together with a heavy duty crossover
with air core inductors, silver plated speaker terminals and Audio Note AN-D internal
wiring.

All the Absolute Zero models share the following design features,

1.) Rear loaded folded quasi parabolic horn with rear facing mouth.

2.) Floorstanding with built-in spikes.

3.) High efficiency, and more importantly best possible dynamic power transfer
behaviour to maximise acoustic output to power input.

In our quest to deliver a compact high sensitivity speaker with good room interface we
have reinvestigated and re-evaluated all the main principles of horn loaded cabinet
designs, and this knowledge coupled with our expertise in system dispersion and
associated crossover design, has resulted in a speaker system that redefines not only
the quality-price relationship at any level which is important when making basic
comparisons to the competition, but more importantly the AZ Series speakers offer an
emotional quotient of reproduced acoustic performances that is quite in a class of its
own.

The vast majority of directly radiating diaphragm designs have very poorly matched
acoustic impedance resulting in the characteristically low efficiency, in contrast a horn
loaded system where a suitable geometric design of the horn mouth and internal
expansion rate allows the acoustic impedance to be optimised to match that of the
driver across several octaves, resulting not just in higher efficiency but also in better
dynamic power transfer from the amplifier..

This better matching achieves two important benefits, firstly the efficiency is greatly
increased and secondly, the resistive termination presented to the diaphragm reduces
the amplitude of any response anomalies.

The greatest problem of horn loaded systems is physical size. For a simple horn the
lower cut-off frequency is directly proportional to the effective diameter of the mouth
when radiating into free space, for example a cut-off frequency at - 3dB of 50Hz would
require a horn mouth area of 3.8 square meter!!

Clearly unsuitable for most domestic purposes.

The most important consideration must therefore be to first reduce the size requirement
whilst maintaining the low frequency response. To do this the rear of the diaphragm
needs to be loaded by an inductive impedance component. This can be designed by re­configuring the parameters of the horn flare to off-set the increasingly capacitive throat
impedance below the cut-off frequency. This, in combination with a speaker position
that takes advantage of close proximity to room boundaries (wall or corner) reduces the
radiation impedance further. With corner positioning the bass horn mouth area is
effectively increased by a factor of x16 or x8 when placed against a wall, providing a
substantial boost at low frequencies.

In the Audio Note AZ-Three Quasi horn, rear diaphragm radiation is controlled by
critically positioned acoustic impedance matched foam, further aiding low frequency
performance by levelling out the amplitude of standing waves.

ROOM PLACEMENT.

In common with our more conventional ported speakers, the Zero AZ Series speakers
are designed to be placed very close and at an angle to a rear wall or preferably with
the rear horn mouth firing assymetrically into a corner close to the side walls, this
positioning has been chosen because being a horn it improves bass response and low
frequency cut off for reasons already discussed.

It is vitally important to understand that the proximity of the AZ-Three to the rear wall
or corner, if you experience problems with the bass, try moving the speaker closer to
the wall, or try to change the angle of the speaker.

The best performance is achieved by corner placement and if placed in a corner, the
AZ-Three should be angled so that the on-axis line of the drive units crosses about 1 - 2
meters in front of you, with the back corner of each speaker almost touching the side
wall (see diagram 1). Even in a hotel room it is possible to reduce to boom and bass