Legacy Whisper XD User manual

Owners Manual For The
Whisper XD
Loudspeaker System

2
Registration
Owners Record 3
The Cabinetry Our Commitment 4
Setup
Speaker Placement 5
Hooking Up Cables 6-7
Amplification 8-10
Speaker Connections 11-12
Installer Calibration Instructions 13
Whisper Wave Launch Processor 14
Technology
Designer’s Notes 15-16
Specifications 17
Table of Contents
Page

3
The serial number is located on the rear of the unit. Record this
number in the space provided below. Refer to this when calling your
dealer regarding this product.
Model: Whisper XD
Serial No: _________________________
Date of purchase: ___________________
Thank you for selecting a Legacy Loudspeaker System. These hand-
crafted instruments will provide you with many years of listening en-
joyment.
Owners Record

4
Handcrafted
Beneath the surface of Whisper XD’s elegant exterior lies rigid MDF
construction. Interlocking joinery maximizes the strength of the cabinet
parts. Polyester fiberfill is selected for internal damping. A sharp rap on
the enclosure will leave you with little more than bruised knuckles.
Each cabinet is impeccably finished on all exposed surfaces with select
veneers. The exquisite finish is hand-rubbed several times to assure a
patina at home with the most elegant decor.
Our Commitment
A great deal of forethought, love and satisfaction is instilled in each piece
of Legacy workmanship. We take pride in getting to know many of our
customers on a first name basis.
Your purchase of this product is backed by the renowned “Legacy
Satisfaction Guarantee”.
The Cabinetry / Our Commitment

5
Positioning Whisper for good performance is quite a bit easier than for most speakers. Remember
that whisper is actually an acoustic gun with a highly controlled directivity pattern. Corner place-
ments are actually quite workable though not necessarily optimal. Whisper will not become
“boomy” like a conventional system and it will not interact strongly with the sidewalls of your room.
Simple Guidelines
1. You may position the Whisper speakers farther apart than most other speakers. This will help to
acoustically shadow the head properly and maintain better channel separation. Experiment with
what works best in your room. As a starting point you might also try the following:
Ideal Speaker spread = (0.8 to 1.2) X Distance from speaker plane to listener position
2. Toe the speakers in more than with other speakers. In most circumstances crossing speaker axes
just in front of the listener’s head works best. This will broaden your sweet spot horizontally. If dis-
persing into an L shaped seating arrangement you might find the best results by aiming the left
speaker at the right most seating position, and the right speaker at the left most seating position.
3. Hearing the most ambience in the recording and the least reflection from your room favors a lis-
tener position that is no farther from the plane of the speakers than two thirds the geometric width
of your room. More simply, if the room is 16 feet wide then the sitting no farther than 12 feet will
allow you to hear more of the recording and less of your room.
Speaker Placement

6
The ideal conductor would have negligible resistance, inductance
and capacitance. The table below shows how a few actual speaker
cables measure up.
Cable Ωs ft pF ft µH ft
12 ga. 0.0033 24 0.21
14 ga. 0.0048 17 0.13
16 ga. 0.0079 16 0.18
18 ga. 0.0128 28 0.21
Capacitance is considered insignificant in each cable because its ef-
fect is well out of the audio bandwidth; inductance can be de-
creased (at the expense of increased capacitance) by keeping the
conductor pair closely spaced.
How long would a cable have to be before inductance effects would
impinge on the audio spectrum? Approximately 300 feet of 12 gauge
would be required to establish a corner frequency of 20 kHz with an
8 Ohm loudspeaker. As you see, inductance is not a problem for
most of us.
Hooking Up Cables

7
What about phase shift due to frequency dependent travel times down the speaker
cable? Measurements show that 100 Hz waves will be delayed about 20 billionths of a
second behind 10 kHz waves when traveling to the end of a 10 foot speaker cable.
Since the cilia of the ear requires 25,000 times longer than this just to transmit phase
information, phase shifting is obviously not the primary concern when considering
speaker cables.
What about resistance? Finally we are getting somewhere. Resistance is the control-
ling factor of the amplifier loudspeaker interface. Excessive resistance can cause ma-
jor shifts of speaker crossover frequencies. The lower the impedance of the loud-
speaker, the greater the effects of series resistance. A 20 foot run of 18 gauge cable
can cause up to 10% deviations of crossover center frequencies. That same 20 feet
can un-damp your damping factor and reduce your systems’ output by one half deci-
bel.
In summary, there are no perfect cables. The best way to approximate the ideal
would be to keep loudspeaker leads as short as is practical.
Hooking Up Cables

8
Ideally the loudspeaker would be among the first components selected when assembling a play-
back system. This would allow the user to choose an amplifier capable of delivering adequate
amounts of current into the frequency dependent load presented by the loudspeaker. However,
when upgrading a system, audiophiles may find themselves matching their new loudspeakers to
their existing amplification. For this reason, extensive measures have been taken to ensure that
each Legacy speaker system represents a smooth, non-reactive load to virtually any amplifier.
Often there is much confusion regarding amplification and loudness levels. It should be under-
stood that the role of the amplifier goes beyond that of driving loudspeakers to a given sound
pressure level. The amplifier should be able to CONTROL the loudspeakers across the entire mu-
sic spectrum. This means that parameters such as damping factor (values greater than 60 are
acceptable) and dynamic headroom should not be overlooked when comparing amplifiers.
Amplification

9
How much power will your new speakers need? That ultimately depends on
your listening environment and musical tastes. As little as five watts per
channel should drive them to a level satisfactory for background music. A
typical 45 watt per channel receiver may fill a room with the compressed
mid-band energy of “heavy metal,” but seem to lack weight or control with
classical recordings. Some audiophiles feel that 200 watts per channel is the
bare minimum to avoid audible clipping distortion when reproducing music
at “live” playback levels. Your Legacy speakers are designed to take advan-
tage of “high-powered” amplifiers, so don’t be afraid to put them through
their paces.
How much is too much power? Rarely is a drive unit damaged by large
doses of music power. More often than not the villain is amplifier clipping
distortion. Even through decades of refinement, loudspeakers are still noto-
riously inefficient transducers, requiring huge amounts of power to recreate
the impact of the live performance. Typically less that 1% of electrical
power is converted into acoustic output. (For example, an omnidirectional
transducer with an anechoic sensitivity of 90 dB @ 1w 1m has a full space
efficiency of only 0.63%)
Amplification

10
When an amplifier is unable to fulfill your loudspeakers demands, a
damaging harmonic spike may be leaked to the high frequency drivers.
Another important point regarding loudness is that the dB scale is a
logarithmic one. This means that a 150 Watt amplifier will potentially sound
only twice as loud as a 15 Watt amplifier. If all of this discussion of power
and loudness seems a bit abstract, consider the example below.
The average acoustical power developed by a person speaking in a
conversational tone corresponds to a mere 0.00001 Watts. The power that
would be developed by the entire population of the city of New York
speaking at once would barely illuminate a single 100 Watt light bulb.
Amplification