Dynaudio pmn manual Delaying Monitors LINE-UP & Calibration, Acoustic summation of audio signals

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DELAYING MONITORS

LINE-UP & CALIBRATION

ITU 775

When using a 5.x set-up with monitors arranged on a circle line (as with ITU 775) the distance from the listener to each of the main monitors is the same.

In case of limited space the three front monitors can be arranged on a straight line. To compensate the center monitor being closer to the listener than the left and right monitor, the center signal can be delayed. To obtain coincident arrival of the sound from all front monitors the delay ranges normally between 0 and 3ms. dependent on the off-set needed.

The speed of sound is approximately 340 m/s or 1130 ft./s.

Approximately 1 ms. of delay will be used per 1 ft. or 30cm, when the monitor has to be "moved" backwards.

Cinema set-up

In the set-up for the cinema the front monitors are always arranged on a straight line. In this case the audience is placed closer to the surround monitors than the front monitor. In order to retain the directional information towards the screen the surround monitors are delayed. Normally the Haas-effect is taken into account. In the listening position the sound from the surround monitors will arrive about 15-20ms after the sound from the front monitors. The delay times involved with cinema processing for the surround channel is dependent on the size of the mixing facility, the cinema, or the home theatre/living room.

The procedure is to calculate the difference in distance between front monitors and the closest surround monitor. Then the time difference is calculated. To this is added 15- 20ms.

Example: From a listening position there are 20 meters to the front monitors and 5 meters to the surround monitors. The difference is (20-15) 15 meters.

The time is 15/340 sec, which equals .044 sec or 44ms. To this is added 15ms. The result is that the surround signal has to be delayed 59ms (or the closest possible).

Acoustic summation of audio signals

The total sound level in the acoustic summation of two sound sources, for example of two monitor monitors, depends upon both the signal and the acoustics. The sound sources can be correlated or uncorrelated.

The listening position (or measurement position) can be either in the direct sound field or in the diffuse sound field. In the direct sound field, there is only one sound direction. This direct field exists either in the open, in a reflection-free room or close to the monitors. The diffuse sound field occurs in a room when you are so far away from the monitors that the portion of direct sound is less than the sum of all the reflections. The distance from the monitors where the direct sound field and the diffuse sound field are equally large is called the critical distance. In a control room, it can typically be 1-3 meters. The near field in front of the monitors can be regarded as a direct field.

Based on all monitors in phase, the sum of the sound pressure from two monitors each playing at the same level is 3 dB, unless the signals are correlated (they are identical) and the sum is measured in the direct field. In this situation the resulting sound pressure level is 6dB higher than the level of the individual monitors.

Acoustic calibration of multi-channel systems Calibration of the acoustic sound levels has been a requirement for many years when working with sound for film, although it has not been particularly common in other branches of the sound industry. However, with the widespread use of multi-channel formats for all forms of music and film presentation in the home, it has turned out to be beneficial to also have the acoustic levels under control here.

It is important to differentiate between production for the cinema and production for 5.1 channel reproduction in the home based upon ITU 775.

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Contents AirUSrev111.qxd 16-12-2004 1414 AirUSrev111.qxd 16-12-2004 1414 Important Safety Instructions Voltage Line plug according to standardQuick Setup Reference AirUSrev111.qxd 16-12-2004 1415 Page c Table of Contents Introduction This ManualBreak Product ConceptRemote Control Common FeaturesMaster Unit Slave & Sub UnitsRear Panel Description Master Master Unit Analog I/OSlave/Sub Optional Digital I/O cardOperational Overview Main DisplayGeneral Setup Procedure AIR Display & Setting UPSetting up Introduction Setups Stereo SetupStereo Setup with mono Subs Stereo Setup with stereo SubsDigital Setup Analog 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 Digital setup This illustration shows how to connect a 5.3 Analog setupThis illustration shows how to connect a 6.1 Analog setup Dig/6 MasterStereo Setup With Chains on L & R Other Chained SetupsDigital 192 kHz Digital Setup When the Monitors are Connected OverviewPress Enter to access the Select Mode Parameter DescriptionBasic operation in all menus Main DisplaySetup Menu SetupSet Monitor Task External ClockPresets In General LFE channel noteRecall StorePlacing the Monitors Other situations Close to wall / WallOn the bridge / Console Phase checking Checking by ear when listening to the signals In phaseEvaluation Checking the placingEqualizing NextCalibrating Main Monitors CurvesInterchannel calibration Acoustic level calibrationPlacing the Subwoofer Low frequency sweeps EvaluationChecking summing phase cancellation To CalibrateControlling standing waves Checking the CrosspointPolarity PhaseLFE Gain Reverberation time AcousticsGood acoustics Sabines formula Absorbers DiffusersMembrane absorbers Absorbtion or diffusion ? Resonance absorbersBackground Info Acoustics Standing WavesRoom modes Axial Tangential RadialHow to prohibit standing waves How does the standing waves influence the sound field?Acoustics Background Info Comb Filtering Or + Dip frequenciesRear wall cancellation Subwoofer Background Info SubwooferSubwoofer & LFE Channel Background Info LFE ChannelCross-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 Preset 1/3 and 2/4 keys Volume potentiometerREF Level 1-3 keys Shift keyAIR Soft Navigating AIR SoftMain ToolsPreset List NetworkSystem Setup Calibrate AIR Base Chained monitorsReset Procedures MiscellaneousGlobal Parameters Local ParametersCables TC Link Standard Cat-5 cablesAES/EBU Standard cables Serial to Cat-5 cableAIR 6 & AIR 15 Master and Slave AIR 20 & AIR 25 Master and SlaveGeneral for all Products AIR Base-1 & AIR Base-2Room & Distance AIR Remote specs AIR RemoteDelay in System & Error Messages ETC Error messages etcAIR Certificate of ConformityCertificate Of Conformity Preset List # Name

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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