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ACOUSTICS - BACKGROUND INFO

Absorbers

All materials in the room act acoustically even if they are not so-called acoustical materials. Basically we have three kinds of absorbers.

Membrane absorbers

This kind of absorber includes wooden floors, windows, doors, etc. This absorber provides absorption in the low end of the frequency range. The efficiency is normally not very high, but under normal conditions large areas are included in the basic room construction. Special designed membrane absorbers can be very effective.

Diffusers

A diffuser provides diffuse reflection of the sound radiated against it. It can be a very useful solution in cases where reflections are disturbing the sound image and it is not advisory to ad further absorption. So in order to reduce flutter echoes, comb filtering etc., special elements can be placed on the "disturbing" surface. These elements must have dimensions comparable to the frequencies at which diffusion is wanted.

Absorbtion or diffusion ?

Resonance absorbers

Resonance absorbers include slit panels, perforated plate, Helmholtz resonators etc. These absorbers are normally used in the frequency midrange. The absorption is medium to high.

Porous absorbers

These absorbers include mineral wool, carpets, curtains, and so on. They can be very effective, but the thickness of the material has to be taken into account. Thin layers will only absorb the highest frequencies. (Think of a rehearsal room in the concrete basement where the only damping is a carpet on the floor: Not good at low frequencies!)

To absorb a given frequency (and all frequencies above) the thickness of the absorber must be the quarter of the wavelength of that frequency. Or: the front of the material must be placed at a distance of one quarter of the wavelength.

A special technique developed by Manfred Schroeder is very capable in making a smooth and controlled diffusion. These diffusers normally referred to as "Schroeder Diffusers" can be found as prefab modules.

 

 

 

 

 

 

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Cross section of one example of the Schroeder Panel.

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Dynaudio pmn Absorbers, Diffusers, Membrane absorbers, Absorbtion or diffusion ? Resonance absorbers, Porous absorbers

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.