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4 How can I add BACCH™ 3D Sound to my Hi-Fi system?

BACCH™ 3D Sound is a recent breakthrough and while it has been perfected and made ready for home use, it is not available on the audio market because it requires a high-level of in-situ customization.

A working prototype for a standalone processor called the BACCH-SP (for "BACCH Stereo Purifier") has been built by Prof. Choueiri and will be commercialized in 2013. It allows any listener to quickly design and apply his or her individual i-BACCH filters.

For BACCH™ 3D Sound to work effectively, detailed acoustic measurements of the listener’s audio system, loudspeakers, listening room, and individual characteristics (ears, head, torso), must be conducted by an expert acoustician, in the audiophile’s listening room, using advanced hardware and software especially developed for the design of customized BACCH™ 3D Sound filters.

The acoustician comes on site and hooks up a rig of instruments to the audiophile’s hi-fi chain. He then asks the audiophile to sit in his favorite listening seat and places special miniature microphones in the audiophile’s ears. The instrument rig then emits a set of test tones through the audiophile’s hi-fi chain and loudspeakers, and the signal captured by the in-ears microphones is recorded in high definition on a computer. The signal contains all the relevant acoustic information about the audiophile’s hi-fi chain, loudspeakers, listening room, head, torso and ears, and is used by the filter design software to design, on the spot, the customized BACCH filter needed to implement BACCH™ 3D Sound for that set-up and listener.

The filter (which is essentially a file of 32-bit numbers) is then loaded in the digital processor unit, which is installed seamlessly and transparently in the audiophile’s hi-fi chain. Many filters can be loaded in the processor, corresponding to various listening positions, and various listeners (e.g. the audiophile’s spouse and family members). A few universal filters (called i-BACCH filters) will also be loaded in the unit. These universal filters are designed using, in place of the audiophile’s own head, a special dummy head with microphones in its ears. When these filters are selected instead of the customized versions, they allow anyone to listen to the 3-D audio of BACCH™ 3D Sound, albeit with a slightly decreased spatial fidelity than the audiophile hears with the customized filters.

Audtech Associates (US) and Elpine Technologies Ltd are licensed to use BACCH™ 3D Sound technology only for customized audiophile installations.

Inquiries should be sent to Audtech Associates via email to: j5652c@alumni.Princeton.EDU or to Elpine Technologies to info@elpinetech.com.