Avalon Acoustics AVALON INDRA User manual

SERIAL NUMBERS:________________
HANDCRAFTED BY:
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INDRA
R
DESIGNED BY NEIL PATEL FOR AVALON ACOUSTICS
This product is certified to meet the requirements of the European Union (EU)
Electromagnetic Compatibility (EMC) Directive (89/336/EEC). Because the permanent
magnets attached to the loudspeaker drivers produce magnetic fields, it is
recommended that the product not be positioned in very close proximity to computer
monitors or television sets.

Table of Contents
1 Introduction ............................................................................................................................4
2 Unpacking Instructions..........................................................................................................5
Introduction...........................................................................................................5
Contents ................................................................................................................5
2.1 Opening the Crate ....................................................................................................6
2.2 Installing the Grilles.....................................................................................................7
Orientation of the Felt Anti-Diffraction Mask ..................................................7
2.3 Replacing Grille Pins ...................................................................................................7
3 Wiring Instructions ..................................................................................................................10
Introduction...........................................................................................................10
Connecting the Speaker to the Amplifier .......................................................10
4 Break-in Period.......................................................................................................................11
5 Maximizing Performance......................................................................................................12
Break-in ..................................................................................................................12
Grille Assemblies ...................................................................................................12
Speaker Placement and Symmetry .................................................................12
Toe-In......................................................................................................................13
Apex™ Couplers ..................................................................................................13
First Reflection Points ...........................................................................................14
Corner Treatment.................................................................................................14
6 Care of Your Loudspeakers ..................................................................................................15
Cabinet (Hardwood Finish) ................................................................................15
Grille Assembly......................................................................................................15
Drivers .....................................................................................................................15
7 Warranty..................................................................................................................................16
In the Event of a Problem ...................................................................................16
Warranty Statement ............................................................................................17
8 Room Acoustics and Speaker Position ...............................................................................19
Introduction...........................................................................................................19
An Optical Analogy.............................................................................................20
Basic Room Acoustics .........................................................................................20
8.1 Standing Waves..........................................................................................................21
8.2 Flutter Echo ..................................................................................................................22
8.3 Early Reflections..........................................................................................................23
Avoiding Early Reflections ..................................................................................24
8.4 Bass reinforcement.....................................................................................................26
8.5 Summary of Recommendations .............................................................................30
Flutter Echo and Standing Waves ....................................................................30
Speaker Placement.............................................................................................31
Early Reflections ...................................................................................................31
8.6 A Listening Room Example .......................................................................................32

9 Accuracy of Bass Reproduction.......................................................................................... 33
Introduction .......................................................................................................... 33
9.1 Sensitivity to Time-Related Information.................................................................. 34
"Fast Bass" .............................................................................................................. 34
9.2 Rationale ..................................................................................................................... 35
Anechoic vs. In-Room Frequency Response ................................................. 35
9.3 Measurements of Audio Equipment ...................................................................... 36
A Correlation with Amplifier Measurements................................................... 36
Loudspeaker Measurements............................................................................. 37
Designing for Accurate Bass Reproduction ................................................... 38
Frequency Response Effects ............................................................................. 39
Listening for Size Distortions ................................................................................ 39
Transient Response Effects ................................................................................. 40
9.4 Conclusion .................................................................................................................. 41
10 Features ................................................................................................................................ 42
11 Specifications ...................................................................................................................... 43
12 Notes..................................................................................................................................... 44

4
1 Introduction
Congratulations on your purchase of AVALON INDRA, one of the most
technologically advanced high-energy transducers ever created.
INDRA represents the culmination of 20 years of research and development in
the areas of transient response, bandwidth, noise floor and octave-to-octave
energy balance. The result sets a new standard for realistic reproduction of
the complete musical event. More than just transparent and dynamic, INDRA
has the groundbreaking ability to recreate a holographic sound-field
completely free of the loudspeaker cabinet and room boundaries. INDRA will
reveal the most subtle nuance and detail of the musical performance in
three-dimensional space.
Utilizing proprietary crossover technologies and drivers consisting of the
lightest and most inert diaphragm materials of Nomex/Kevlar and ceramic,
INDRA can instantly respond to the most demanding musical passages.
Revolutionary crossover damping networks virtually eliminate driver overhang
and energy storage. Multiple layering and material usage in our legendary
cabinet construction eliminates cabinet resonance allowing for a continuous
musical flow like no other loudspeaker.
All AVALON ACOUSTICS loudspeakers are designed and built to the highest
standards in the audio industry. Hand assembled by dedicated craftsmen
and technicians, each loudspeaker is measured and matched creating
perfect symmetry and coherency. Before leaving the factory each of our
masterpieces are subjected to a demanding array of quality control and
testing procedures to assure flawless and consistent performance.
www.avalonacoustics.com

5
2 Unpacking Instructions
Introduction
Your AVALON ACOUSTICS loudspeakers were shipped in a heavy-duty crate to
ensure their safe arrival. It is recommended to save these crates for possible
future use. Due to the weight of the speakers, it will require two persons to
un-crate them and position them for listening. Please arrange for your dealer
or another able bodied person to assist in this project.
Contents
The shipping crate contain the following items:
two loudspeaker cabinets
two grille assemblies
the owner’s manual
one set of six Apex™ Couplers
an accessory bag
The grille assemblies and owner’s manual are contained in an outer
compartment on the top of the shipping crate. The Apex™ Couplers and
accessory bag are packed together on the bottom of one of the
loudspeaker cabinets.
The accessory bag contains replacement grille pins, a small bottle of furniture
polish, and two lint-free polishing cloths.
IMPORTANT: It is imperative that the Apex™ Couplers are utilized, in order to
insure that the bottoms of the loudspeakers are not blocked. This is especially
important on thick carpeting.

6
2.1 Opening the Crate
The crate features a one-piece top assembly which is fastened to the crate
bottom with screws around the lower perimeter. To unpack, remove the
screws and lift the upper portion of the crate straight up (this will require two
people).
Next, slide each speaker part way off of the crate base so that the plastic
bag can be unfastened from the enclosure bottom. Stand the speaker up
and the bag can be slid off the top. Please refer to Figure 2.1.
Figure 2.1 - To unpack the loudspeakers.
1. Remove screws.
2. Lift case.
3. Slide speaker,
then undo bag.
4. Stand speaker up,
then remove bag.



7
2.2 Installing the Grilles
The grille assemblies are behind a panel on the outside of the speaker crate.
Remove the screws securing the panel, and then carefully pull the grilles
straight out. The grilles are installed with friction fasteners and press into place
on the speaker cabinets. Please see Figure 2.2.
Orientation of the Felt Anti-Diffraction Mask
The grille assembly includes a felt anti-diffraction mask. Should the felt mask
be removed, be sure to note the correct inside-outside orientation when
re-installing it. The tweeter and midrange openings are beveled on the side
that faces the listener (away from the speaker).
Figure 2.2 - To install the grille assemblies.

8
2.3 Replacing Grille Pins
The grille pins installed on the grille assemblies are fragile and can be easily
damaged. Should any of the pins break, you may replace them using the
following procedure.
1. Place the grille assembly face-down on a padded surface (a towel or
carpeting).
2. Remove the damaged grille pin by pulling it straight out with a small pliers
or similar tool. Please refer to figure 2.4. Make sure that the complete pin is
removed and that there are no pin fragments left in the mounting hole.
3. Insert the new grille pin in the grille pin installation tool (see figure 2.5).
Figure 2.4 - Removal of broken grille pin. Check for pin fragments in
the mounting hole.
Figure 2.5 - Insertion of new grille pin into installation tool.

9
4. Carefully pull the grille cloth away from the frame mounting hole. The
mounting hole must be clear of all obstacles during pin installation.
5. Place the exposed end of the grille pin in the open mounting hole. Check
to insure that the grille cloth is not trapped between the pin and frame. Use a
small hammer and gently tap the new grille pin in place. Then, pull the
insertion tool off the new pin and verify that the pin flange is flush with the
surface of the grille. Please refer to Figure 2.6.
WARNING: Grille pin breakage may result if the grille cloth becomes trapped
between the pin and frame during installation.
6. Reposition the grille cloth that was pulled away from the frame mounting
hole in step 4. The cloth should lay flat and wrinkle-free.
Figure 2.6 - Installing grille pin into INDRA grille frame. Note that after
installation, the grille pin flange is flush with the surface of the grille.

10
3 Wiring Instructions
Introduction
The crossover is housed in a sealed, non-accessible chamber in the bottom of
the speaker cabinet, to minimize the effect of vibration on the components.
The INDRA is equipped with high-quality binding post for connecting the
speaker cables. Spade lugs are recommended for all cable terminations.
Connecting the Speaker to the Amplifier
1. Place the speaker in its approximate location, then lay the speaker on its
side, using a soft surface to avoid scratching the finish.
2. Connect the speaker wires to the terminal block on the speaker bottom
(see Figure 3.1). Check to insure the correct polarity (positive lead connected
to the (+) terminal and negative lead connected to the (-) terminal.
Do NOT over-tighten the screws.
Figure 3.1 –Back view of the speakers showing the connections from the
amplifier to the loudspeaker. Check to insure the correct polarity (positive lead
connected to the (+) terminal and negative lead connected to the (-) terminal).

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4 Break-in Period
Your new AVALON ACOUSTICS loudspeakers have an initial break-in period. They
will not perform to their full sonic potential when first installed in your system.
This is partially due to a residual polarization of the dielectric materials used in
the crossover capacitors and internal wiring.1As music is played through the
loudspeakers, the electrical signal will gradually anneal these materials.
Similarly, the suspensions of the drivers will reach their optimal mechanical
properties as the speakers are played. Only after the break-in period will the
full performance of your AVALON ACOUSTICS loudspeakers be realized.
The break-in process will occur naturally as music is played through the
system. To reduce the time required, it is recommended that the system be
played continuously, using either a digital source in the repeat mode or an
FM broadcast signal. The recommended break-in procedure is as follows:
Initial warm-up: three to six hours of quiet music.
Extended break-in: 200 to 300 hours of loud and dynamic source
material (e.g. Tangerine Dream, Optical Race, RCA 2042-2-P).
During the break-in period, the sonic properties of your loudspeakers may
undergo several gradual shifts as the various components break-in at different
rates. It is therefore suggested that the fine-tuning of the system be delayed
until after the break-in period is completed. However, during the final phases
of the break-in period, the sonic image will open up, the sound-stage will gain
specificity, the bass control and impact will increase, and the overall sound
will have a more relaxed, involving presentation.
1A high-voltage test is applied to wiring and capacitors during their manufacture.
This results in a residual polarization of the dielectric materials.

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5 Maximizing Performance
These details are imperative to obtaining optimum results from your AVALON
ACOUSTICS loudspeakers.
Break-in
The break-in period is critical to maximizing sonic performance and should
take place before other adjustments (see the discussion on page 11). The
break-in should begin with three to six hours of quiet music, followed by 200 to
300 hours of loud and dynamic source material.
Grille Assemblies
The grille assemblies, with their felt anti-diffraction masks, are integral elements
of the loudspeakers' design. Unlike many other products, AVALON ACOUSTICS
loudspeakers are designed to be used with the grilles in place while listening,
and removing them will degrade the system's performance. It is extremely
important that the felt anti-diffraction masks make physical contact with the
face of the loudspeakers, as air space between the felt and the speaker face
will adversely affect sound quality.
Speaker Placement and Symmetry
Selecting the proper room position for your AVALON ACOUSTICS loudspeakers
can dramatically improve their performance. The following points highlight
the fundamental concepts in loudspeaker positioning from the in-depth
discussion in Chapter 8, Room Acoustics and Speaker Position (beginning on
page 19):
Left to right room symmetry aids in producing a balanced sound
stage.
Image depth is enhanced when the distance to the rear wall is
increased.
The most even bass response will be attained when the distances to
the side and rear walls are not overly similar.

13
Toe-In
Adjusting the toe-in angle of the speakers is useful in tailoring the sound to
best match the characteristics of your system and listening room.
When the speakers are facing straight forward, they tend to create a large,
expansive sound-stage, painted with broad brush strokes. As they are rotated
toward the listening position, the image becomes more compact, with
increased focus, creating a greater sense of intimacy. Pointing the speakers
inward is also helpful in situations where strong reflections from the side walls
are a problem.
Start with the loudspeakers facing straight forward, and play either a mono
source, or a stereo source with a distinct center image, through both
channels. Carefully rotate the loudspeakers inward in small increments to
bring the image in precise center focus (small adjustments can be made with
the speaker on Apex™ couplers). Toe-in adjustment is rather delicate, and
experimentation is necessary to achieve the proper angle for your listening
situation. The optimum angle is usually between three and ten degrees
inward.
Apex™ Couplers
Supplied with your AVALON ACOUSTICS loudspeakers are six Apex™ couplers,
used to couple the speakers to the floor, thereby minimizing time-smearing
resonance effects. The result is an increase in focus and solidity of the sonic
images.
On hardwood floors, you may protect the floor from the pointed spike using a
large coin, such as a quarter. However, the coupling effect of the Apex™
couplers will be reduced.
Once you have located the proper position and toe-in angle for your AVALON
ACOUSTICS loudspeakers, place the couplers under the speaker bases. It is
easiest to install the couplers with the assistance of a friend. Lean the speaker
forward first, and position two couplers pointing downward, one under each
rear corner. Then lean the speaker backward and place one Apex™ coupler
under the front center of the base.
IMPORTANT: It is imperative that the Apex™ Couplers are utilized, in order to
insure that the bottoms of the loudspeakers are not blocked. This is especially
important on thick carpeting.

14
First Reflection Points
Since the ear/brain system tends to integrate the sounds arriving within a 10
millisecond time window, it is important to control the early reflections arriving
from the sidewalls to the listening position. A hard-surfaced wall can produce
a strong frequency-dependent reflection that can interfere with the
reproduced sound-stage, as well as change the perceived tonal balance of
the system. Therefore, damping these first reflection points is strongly
recommended. Please refer to Section 8.3, Early Reflections, beginning on
page 23, for further information.
Corner Treatment
It is important to control the first reflections of low frequency sound, which
normally occur at the corners behind the loudspeakers. These reflections can
cause significant distortions in phase and amplitude, resulting in muddy bass
definition and smeared bass transients. Placing DAADS (more information
available at www.acusticaaplicata.com ) at the room corners can
significantly control these bass colorations and restore the quickness of bass
transients.

15
6 Care of Your Loudspeakers
Cabinet (Hardwood Finish)
AVALON ACOUSTICS’ hardwood finished loudspeakers are supplied with a
special polish and two lint-free polishing cloths, in order to properly care for
the high quality furniture lacquer. The following polishing instructions should be
observed:
IMPORTANT: Use the supplied furniture polish ONLY. Do NOT use cleaners that
contain ammonia, strong solvents, or abrasive materials. Use of these
materials can degrade, scratch, or even DESTROY the finish.
1. Apply the supplied polish to one of the clean, lint-free polishing cloths (or
use cotton cloth that is clean and lint-free), and carefully wipe it on the
cabinet. Be careful NOT to apply the polish to the loudspeaker drivers.
WARNING: Do NOT apply polish to the loudspeaker drivers.
2. Wipe off the excess polish until the desired luster is achieved.
Grille Assembly
The grille assembly may be removed from the cabinet and gently vacuumed
to remove dust. If the felt insert is removed, please note the inside-outside
orientation when re-installing it. The hole for the tweeter is beveled on the side
toward the listener, to provide optimal dispersion characteristics.
Drivers
The drivers require no regular maintenance. Do not attempt to clean the
tweeter dome, as they are easily damaged. If desired, you may remove dust
from the woofer cone by using a small, soft dusting brush.
WARNING: The drivers in this transducer are coupled in a more intricate
manner; SEVERE DAMAGE may result from the removal of these drivers. All
service must be performed by an authorized representative of AVALON
ACOUSTICS.

16
7 Warranty
Your AVALON ACOUSTICS loudspeakers are warranted to the original, registered
purchaser against defects in workmanship and materials for a period of three
years from the date of first purchase, provided that the enclosed registration
card is returned to the factory within seven days of the purchase date. If the
registration card is not returned within the seven day period, this warranty is
null and void, and you will not be notified of future updates. In the unlikely
event that you did not receive the registration card with your loudspeakers,
please contact the factory immediately so that we may send you a
replacement card. The warranty period is in effect from the date that the
product leaves the factory. This warranty is non-transferable to subsequent
purchasers within the original three year period. A complete statement of
warranty is given below. Please take the time to fill out and return the
enclosed warranty registration card.
In the Event of a Problem
In the unlikely event of a problem with your AVALON ACOUSTICS loudspeakers,
the component most susceptible to failure is one of the driver units. If driver
replacement is required, have your dealer contact AVALON ACOUSTICS. The
performance curves of the drivers in each pair of loudspeakers are kept on
file at the factory. This enables AVALON ACOUSTICS to supply an exact
replacement unit, ensuring continued operation at the highest level of
performance. The defective driver must then be returned to the factory for
inspection to determine the status of the warranty claim. This on-site
replacement of the driver units eliminates the time and expense of shipping
the entire speaker to the factory for repair. All warranty claims must be made
through an authorized AVALON MULTICHANNEL SYSTEMS/AVALON ACOUSTICS dealer
or distributor.

17
Warranty Statement
1. AVALON ACOUSTICS warrants the materials, workmanship, and proper
functioning of this product for a period of three years to the original registered
purchaser, provided that the completed registration card is returned to
AVALON ACOUSTICS within seven days of the date of purchase. If the registration
card is not returned to the factory within the seven day period, this warranty is
null and void. If any defects are found in the materials or workmanship of this
AVALON ACOUSTICS product, or if the product ceases to properly function within
the appropriate warranty period from the date of first purchase, the unit will
be repaired or replaced by AVALON ACOUSTICS or its authorized agent after
receiving authorization from the factory or dealer. This warranty is not
transferable.
Unauthorized dismantling of this product will render this warranty void.
2. Purchaser must obtain an RMA number by contacting dealer/distributor
and return the product, packaged in the original shipping carton, freight
prepaid. Shipping address will be provided at the time the RMA number is
issued. No returns will be accepted without prior authorization.
3. AVALON ACOUSTICS reserves the right to inspect any products which are the
subject of warranty claim prior to repair or replacement. Final determination
of warranty coverage lies solely with AVALON ACOUSTICS and only products
which are determined to be covered under this warranty shall be repaired or
replaced by AVALON ACOUSTICS. The customer will be informed of any delays
and AVALON ACOUSTICS will provide replacement as quickly as possible.
Out-of-warranty claims will be billed for labor, materials, return freight, and
insurance as required. Any product for which a warranty claim is accepted
will be returned to the purchaser and cost of return shipping and insurance
will be factory prepaid within the boundaries of the USA. Units to be shipped
outside of the USA will be shipped freight collect only. This warranty gives
specific legal rights. The purchaser also has implied warranty rights, and may
also have other rights which vary from state to state.
4. This warranty is extended to the original registered purchaser for value.
5. AVALON ACOUSTICS strives to manufacture the very finest possible equipment,
and therefore reserves the right to make changes in design and
improvements upon its products, without necessarily assuming an obligation
to retrofit such changes upon its previously manufactured models.

18
6. The above warranty is the sole warranty given by AVALON ACOUSTICS, and is
in lieu of all other warranties. All implied warranties, including warranties of
merchantability or fitness for any particular purpose shall be strictly limited in
duration to three years from the date of shipment from the factory, and upon
the expiration of the warranty period (three years), AVALON ACOUSTICS shall
have no further obligation of any kind whether express or implied, including
but not limited to merchantability. Further, AVALON ACOUSTICS shall in no event
be obligated for any incidental or consequential damages as a result of any
defect or any warranty claim, whether express or implied. Some states do not
allow exclusion or limitation of incidental or consequential damages or
limitations on how long implied warranties last, so the above limitations and
exclusions may not apply to you.
7. AVALON ACOUSTICS does not authorize any third party, including any dealer
or sales representative to assume any liability for AVALON ACOUSTICS, or make
any warranty for AVALON ACOUSTICS. The unit must not have been altered or
improperly serviced or repaired. The serial number on the unit must not have
been altered or removed.
8. Warranty registration cards must be completed and mailed to AVALON
ACOUSTICS within seven days of date of purchase; otherwise, this warranty is
null and void. AVALON ACOUSTICS may, at its option, require from the purchaser
valid proof of purchase (dated copy or photocopy of dealer's original
invoice).
9. If this product is used in a commercial or industrial application, then special
warranty exclusions may apply. Contact your dealer or AVALON ACOUSTICS for
commercial warranty policies.

19
8 Room Acoustics and Speaker Position
Introduction
The listening room forms the final link of the playback system, as important as
any other component in the chain. Just as an otherwise superb system is
handicapped by an inferior pre-amplifier (for example), so can a
well-matched system be hindered by poor room acoustics. It is not necessary
to listen to your system in a specially-designed sound chamber in order to
enjoy it. In fact, a dedicated listening room usually requires additional sound
treatment, due to a lack of other items in the room that can help provide
good acoustics. However, a degree of attention to set-up can greatly
increase your listening satisfaction, no matter what your listening situation.
Listening in a properly set-up room can be a startling experience. Due to the
limitations of the two-channel format and the listening environment, the
illusion of actually being transported to the recording site cannot usually be
achieved. However, an uncanny sense of realism can be created. Perhaps it
is best described as if the front half of your listening room has been removed,
so that it now opens out into the recording site.
To optimize your equipment set-up and the listening-room acoustics requires a
basic understanding of the principles which affect the propagation of sound
in the room. Also, we will discuss the way in which our brain interprets spatial
cues, and how the room acoustics can affect our sonic perceptions.

20
An Optical Analogy
Let us use a visual analogy to aid our understanding of acoustics. Imagine
that you are in a room that is lit only by a candle in its center. There is
(approximately) a uniform amount of light cast in all directions. If a large
mirror is held closely to candle, one half of the room becomes darkened,
while the other half receives twice as much light. This is because there are
effectively two candles now illuminating that half of the room, the real
candle, and the virtual (or reflected) candle. The energy that had been sent
to both sides of the room has now been concentrated in one side only.
If we repeat the same experiment using a large piece of black cloth instead
of a mirror, the results will be somewhat different. The side of the room behind
the cloth is darkened, just as before, but the level of light on the side of the
candle remains unchanged. This is because the light is absorbed by the cloth,
rather than being reflected back into the room.
Thus we can see that the energy can either be absorbed or reflected. A
similar situation occurs with sound waves, although we must account for the
much greater wavelengths of audible frequencies. Of course no material is a
perfect absorber or an absolute reflector. Furthermore, the sonic absorption
coefficient of a given material usually varies with frequency.
Basic Room Acoustics
The great majority of all listening rooms are rectangular, with parallel surfaces.
The walls and ceiling are typically hard surfaces, which are acoustically
reflective. These large areas are the predominating factors in the overall room
acoustics, although the other items in the room (furnishings, carpeting, wall
hangings, doorways, etc.) will also play a role. Without going into excessive
detail, there are four primary areas of potential concern:
1. Standing waves.
2. Flutter echo.
3. Early reflections.
4. Bass reinforcement.
The first three items are problems which should be reduced or eliminated. The
last item, bass reinforcement, needs to be matched to the entire system for
proper tonal balance.