16.01.15

Amina Technologies i-Series Invisible Loudspeakers are Ideal for the Latest Immersive Home Cinema Audio Formats

AMina-Auro3D-21

The most recent innovations in cinema audio technology are fully immersive, three dimensional sound systems, the main proponents of this ...

The most recent innovations in cinema audio technology are fully immersive, three dimensional sound systems, the main proponents of this being Dolby with its Atmos object-based system and Auro-3D from Auro Technologies, which uses additional height layers of speaker channels. In high quality installations both systems require additional discrete speakers compared to the current standard 5.1, 7.1, etc. surround sound formats. Atmos requires additional speakers to be positioned above the audience in the ceiling whilst Auro-3D calls for a “height layer” of speakers to be placed high on the walls with the option for a single “top layer” speaker in the ceiling. [caption id="attachment_7832" align="aligncenter" width="668"]Whichever format AV professionals specify for their clients (high-end home cinemas will often cater for both), the audio system design will probably require speakers to be placed in the ceiling. Whichever format AV professionals specify for their clients (high-end home cinemas will often cater for both), the audio system design will probably require speakers to be placed in the ceiling.[/caption] What does this all mean when it comes to specifying suitable loudspeakers? Amina Technologies see AV professionals being faced with two important issues:
  1. How to achieve a clean, flat ceiling finish in home cinemas that don’t feature a dropped fabric ceiling?
  2. How to ensure the whole audience receives consistent sound pressure and sound quality from ceiling speakers which are typically much closer to the listening position, thereby magnifying any dispersion inadequacies they might have?
With over 15 years of experience designing and manufacturing invisible loudspeakers, Amina Technologies have developed DMLs (distributed mode loudspeakers) to a point far beyond most peoples’ expectations for hidden loudspeaker performance. By using flat, lightweight, rigid vibrating panel technology their speakers are designed specifically to be flush mounted and plastered directly onto with standard 2mm thick trade finishes. This solves the aesthetic issue. Plus, against conventional perceived wisdom, the resulting sound quality is not “muffled”. Of course, if conventional speakers were plastered over the sound would be “muffled”…. at best! When specifying in-ceiling speakers in order to achieve a required coverage pattern the dispersion angle of the speaker needs to be known in order to calculate the spacing between speakers. Simple geometry says that the lower the ceiling, the closer the speakers need to be to achieve the desired goal. Alternatively the speakers may need to be changed to ones that have a wider dispersion angle. [caption id="attachment_7834" align="aligncenter" width="670"]A dispersion angle of 180 degrees would be ideal and this is one of the many useful characteristics of Amina’s speakers. A dispersion angle of 180 degrees would be ideal and this is one of the many useful characteristics of Amina’s speakers.[/caption] In a home cinema the quantity of speakers, however, is normally dictated by the number of channels required. And even if a large room system is specified with 4 in-ceiling Atmos speakers, there is likely to be a situation where certain speakers are at quite an acute angle in relation to listening positions on the other side of the room. Therefore the only solution to achieve consistent tonal quality for all listeners is to use speakers with wide dispersion. A dispersion angle of 180 degrees would be ideal and this is one of the many useful characteristics of Amina’s speakers. This is achieved because unlike a conventional speaker, which behaves like a piston where dispersion is directly related to the size of the radiating area (larger cones have narrower dispersion), a DML uses bending waves which inherently radiate all frequencies over 180 degrees. It’s the same principle that endows many musical instruments, such as the acoustic guitar, violin or piano, with such excellent room-filling, audience pleasing properties. But what about other performance parameters such as power handling, sound pressure level (SPL) and frequency range? Amina Technologies recommend that AV professionals specify the following products for home cinemas and media rooms based on their recently upgraded Evolution i-Series: Model              Max Power     Max SPL @1.4m         Max SPL @2m                        Frequency range AIW350i         60W                99dB                           96dB                           100Hz – 20kHz AIW550i         100W              104dB                         101dB                         100Hz – 20kHz AIW750i         200W              107dB                         104dB                         50Hz – 20kHz www.amina.co.uk