Avalon Acoustics Sentinel manual An Optical Analogy, Basic Room Acoustics

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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.

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Contents Musical Masterpieces Page Table of Contents Introduction Listening Position Introduction OverviewLow Noise Floor Coherent Energy Transfer Active Reference System Contents Unpacking InstructionsIntroduction Room Preparation and Verification Crate and Box Placement for Unpacking Room set-up for unpackingOpening the Crates To unpack the crossover cabinetsTo unpack the upper speaker cabinets Opening the Sub Amplifier Crates System Set-up PreparationRemoving Apex‘ Couplers from Set-up Blocks Left / Right Channel Matching Installation of Apex‘ couplers Lower Speaker Cabinet Set-upUpper Speaker Cabinet Set-up Page Page Proper placement of crossover cabinet behind speaker Crossover Cabinet Set-upFelt Anti-Diffraction Mask Orientation of the upper Felt MaskSub Amplifier Set-up Wiring Instructions Do not over-tighten the screwsWiring and Field Interactions Inductive field effectsConnecting Upper Speaker Cabinet to Crossover Do not over-tighten the binding postsConnecting Speaker Cable to the Crossover Connect Speaker Cable to your Amplifier Connecting Subwoofer to the Sub Amplifier Connecting Preamplifier to the Amplifiers Interconnect Y-cable at the preamplifierTwo outputs at the preamplifier Break-in Period Subwoofer Amplifier Design PrincipleRoom Compensation Master Maximizing Performance Separate Left / Right AmplifiersFelt Anti-diffraction Masks Room Treatment and System / Listener Position Toe-InApex‘ Couplers First Reflection Points Corner TreatmentCrossover Cabinet Care of Your Avalon LoudspeakersCabinet DriversWarranty Event of a ProblemWarranty Statement Page Room Acoustics / Speaker Position An Optical Analogy Basic Room AcousticsStanding Waves Flutter Echo Early Reflections Avoiding Early Reflections Angle Angle Y Reflected Sound Direct Sound Low Frequency Reflections Bass reinforcement 100 200 500 Page Summary of Recommendations Flutter Echo and Standing WavesSpeaker Placement Early ReflectionsListening Room Example Listening Position Path Length SymmetryTime Alignment Summary Accuracy of Bass Reproduction Sensitivity to Time-Related Information Fast BassMeasurements of Audio Equipment Correlation with Amplifier MeasurementsLoudspeaker Measurements Designing for Accurate Bass Reproduction Listening Qualities Frequency Response EffectsListening for Size Distortions Transient Response Effects Active Subwoofer System Anechoic Frequency Response vs. In-Room Frequency ResponseActive Control of Bass Energy Features Specifications LoudspeakerSubwoofer Amplifier

Sentinel specifications

Avalon Acoustics Sentinel represents a pinnacle in high-fidelity loudspeakers, designed for audiophiles who demand exceptional sound quality and elegant design. Known for their commitment to meticulous craftsmanship and innovative technology, Avalon Acoustics continues to push the boundaries of acoustic performance with the Sentinel model.

One of the standout features of the Sentinel is its unique three-way design. This configuration allows for precise sound reproduction across the entire audio spectrum, delivering rich bass, articulate midrange, and sparkling highs. The speaker utilizes proprietary drivers that have been engineered to minimize distortion while maximizing dynamic range and sensitivity. This ensures that every note is rendered with clarity and precision, making it ideal for any listening environment.

The cabinet design of the Sentinel is another aspect that underscores Avalon's commitment to excellence. Constructed from carefully selected hardwoods and finished to perfection, the enclosure not only enhances aesthetic appeal but also plays a critical role in acoustic performance. Its solid build effectively reduces resonance and undesirable vibrations, allowing the drivers to perform at their best.

In terms of technology, the Sentinel incorporates advanced crossover networks. These networks are designed to ensure seamless transition between drivers, providing a cohesive soundstage. By using high-quality components, the crossover systems significantly improve the overall performance, ensuring that listeners enjoy a balanced and natural tonal quality.

Moreover, the Sentinel features adjustable bass ports, allowing users to tailor the speaker's performance to fit their specific room acoustics. This flexibility helps to optimize the listening experience, regardless of the environment. The speakers also include easy-to-use bi-wiring and bi-amping capabilities, enabling audiophiles to customize their setup for optimal sound quality.

Finally, the visual appeal of Avalon Acoustics Sentinel cannot be understated. With its sleek lines and contemporary design, it is a statement piece that complements any décor. Available in various finishes, the Sentinel seamlessly blends performance with style, catering to both auditory and aesthetic sensibilities.

In summary, Avalon Acoustics Sentinel stands out as an exceptional loudspeaker that combines advanced technology, exquisite craftsmanship, and customizable features. Its three-way design, high-quality drivers, and adjustable features make it a top contender for those seeking unparalleled sound quality in a luxurious package.
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