Dynaudio pmn manual Rear wall cancellation

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ACOUSTICS - BACKGROUND INFO

Rear wall cancellation

When the monitor is set up at some distance in front of a wall, reflections from the wall may occur and influence the perceived frequency response. This could result in comb filtering if all frequencies produced by the monitor were radiated in all directions. But the monitors are typically only omni-directional at low frequencies.

The result of the reflection is a single or few dips in the frequency response perceived in front of the monitor.

This frequency is cancelled because of the oppositely phased reflection

The frequency response may look like this: one cancellation at the frequency that has a wave length of four times the distance to the rear wall.

The dip - or cancellation frequency - is dependent on the distance to the wall. If the distance is 1 m, the first dip frequency will occur at a frequency with a wavelength of 4 m.

l = c / f where

l = wavelength [m] (or ft.)

c = speed of sound [m/sec] (or ft./sec.) f = frequency [Hz]

Hence

4 = 344 / f f = 86 Hz

A closer position will result in a cancellation at a higher frequency. This is then limited by the frequency where the monitor becomes directional and does rot radiate sound to the rear.

A farther position will result in cancellation at a lower frequency. This is limited by the distance being so long, that the reflected sound is attenuated due to the long extra path travel.

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Contents AirUSrev111.qxd 16-12-2004 1414 AirUSrev111.qxd 16-12-2004 1414 Voltage Line plug according to standard Important Safety InstructionsQuick Setup Reference AirUSrev111.qxd 16-12-2004 1415 Page c Table of Contents This Manual IntroductionBreak Product ConceptCommon Features Remote ControlMaster Unit Slave & Sub UnitsMaster Unit Analog I/O Rear Panel Description MasterSlave/Sub Optional Digital I/O cardMain Display Operational OverviewGeneral Setup Procedure AIR Display & Setting UPSetting up Introduction Stereo Setup SetupsStereo Setup with mono Subs Stereo Setup with stereo SubsAnalog Setup Digital SetupThis illustration shows how to connect a 5.1 digital setup This illustration shows how to connect a 5.1 analog setupThis illustration shows how to connect a 5.3 Analog setup This illustration shows how to connect a 5.3 Digital setupDig/6 Master This illustration shows how to connect a 6.1 Analog setupOther Chained Setups Stereo Setup With Chains on L & RDigital 192 kHz Digital Setup Overview When the Monitors are ConnectedParameter Description Press Enter to access the Select ModeBasic operation in all menus Main DisplaySetup Setup MenuSet Monitor Task External ClockLFE channel note Presets In GeneralRecall StorePlacing the Monitors Other situations Close to wall / WallOn the bridge / Console Checking by ear when listening to the signals In phase Phase checkingEvaluation Checking the placingNext EqualizingCurves Calibrating Main MonitorsInterchannel calibration Acoustic level calibrationPlacing the Subwoofer Evaluation Low frequency sweepsTo Calibrate Checking summing phase cancellationControlling standing waves Checking the CrosspointPolarity PhaseLFE Gain Reverberation time AcousticsGood acoustics Sabines formula Diffusers AbsorbersMembrane absorbers Absorbtion or diffusion ? Resonance absorbersStanding Waves Background Info AcousticsAxial Tangential Radial Room modesHow does the standing waves influence the sound field? How to prohibit standing wavesAcoustics Background Info Comb Filtering Dip frequencies Or +Rear wall cancellation Subwoofer Subwoofer Background InfoLFE Channel Subwoofer & LFE Channel Background InfoCross-overs Low Pass LFE GainCinema set-up Delaying Monitors LINE-UP & CalibrationAcoustic summation of audio signals Calibration of 5.1 in an ITU-775 arrangement How to measure the sound pressure?LINE-UP & Calibration Background Info Introduction Remote Control FeaturesAIR Remote Volume potentiometer Preset 1/3 and 2/4 keysREF Level 1-3 keys Shift keyNavigating AIR Soft AIR SoftTools MainNetwork Preset ListSystem Setup Chained monitors Calibrate AIR BaseMiscellaneous Reset ProceduresGlobal Parameters Local ParametersTC Link Standard Cat-5 cables CablesAES/EBU Standard cables Serial to Cat-5 cableAIR 20 & AIR 25 Master and Slave AIR 6 & AIR 15 Master and SlaveGeneral for all Products AIR Base-1 & AIR Base-2Room & Distance AIR Remote AIR Remote specsError messages etc Delay in System & Error Messages ETCAIR Certificate of ConformityCertificate Of Conformity # Name Preset List

pmn specifications

Dynaudio, a company renowned for its high-fidelity audio products, has made significant strides in the field of professional monitoring through its PPM (Professional Precision Monitoring) series. Among the standout models in this series is the Dynaudio PMN (Professional Monitoring Nearfield), which has garnered attention for its outstanding sound quality, precise technical performance, and sophisticated design.

One of the key features of the Dynaudio PMN monitors is their advanced driver technology. Equipped with proprietary drivers, the PMN series employs custom-designed woofers and tweeters that deliver an incredibly accurate frequency response. The woofers utilize a lightweight diaphragm, ensuring that low frequencies are produced with power while maintaining clarity. The tweeters, known for their soft dome design, excel in reproducing high frequencies with exquisite detail and minimal distortion, making the listening experience both immersive and enjoyable.

In terms of design, the PMN monitors boast a sleek and modern aesthetic that fits seamlessly into any studio environment. The cabinet construction employs advanced materials and techniques that minimize resonance, thus reducing unwanted coloration in sound. The unique curved shape of the cabinets is not only visually appealing but also supports optimal acoustic performance by enhancing sound dispersion.

Another notable characteristic of the Dynaudio PMN is its versatility. The monitors are equipped with multiple inputs, allowing for seamless integration into various set-ups, whether in a professional studio or a home listening environment. This flexibility is further complemented by adjustable bass and treble controls, empowering users to tailor the sound profile to their specific requirements.

Dynaudio has also incorporated advanced technologies such as room correction in certain PMN models, which enables precise calibration according to the acoustics of the room. This feature ensures that audio professionals can rely on consistent and accurate sound reproduction regardless of their monitoring environment.

Overall, the Dynaudio PMN series represents a blend of pioneering audio technology, meticulous craftsmanship, and user-focused design. For professionals seeking precise monitoring solutions for music production, film scoring, or any audio-related projects, the Dynaudio PMN monitors provide an exceptional listening experience that stands the test of time. With their stellar performance and innovative features, these monitors have become a top choice for sound engineers, musicians, and audio enthusiasts alike.
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