Princeton University  


  1. BACCH™ 3D Sound: 20 Questions and Answers
  2. BACCH™ 3D Sound (previously called "Pure Stereo 3D Audio™") is a recent breakthrough in audio technology, based on BACCH™ Filters, (and licensed by Princeton University) that yields unprecedented spatial realism in loudspeaker-based audio playback allowing the listener to hear, through only two loudspeakers, a truly 3D reproduction of a recorded soundfield with uncanny accuracy and detail, and with a level of high tonal and spatial fidelity that is simply unapproachable by even the most expensive and advanced existing high-end audio systems.

    This paper is the PDF version of the 20 Questions and Answers that are posted online at this webpage. This poster summarizes the fundamental principles behind this technology as well as some technical aspects of its implementation.

  3. BACCH™ Filters: Optimized Crosstalk Cancellation for 3D Audio over Two Loudspeakers
  4. BACCH™ Filters are optimized crosstalk cancellation (XTC) filters that allow 3D audio reproduction over a pair of loudspeakers. They yield maximum crosstalk cancellation level without introducing any spectral coloration to the input signal. An introduction to BACCH™ Filters can be found here.

    BACCH™ Filters are at the heart of BACCH™ 3D Sound, Dynasonix, and other emerging technologies from the 3D3A Lab.

    This highly technical paper describes most of the basic aspects of BACCH™ Filters (some aspects are not published for propriety reasons).

  5. PHOnA: A Public Dataset of Measured Headphone Transfer Functions
  6. The Princeton Headphone Open Archive (PHOnA) is a dataset of measured headphone transfer functions (HpTFs) from many different research institutions around the world. Visit this webpage to access the dataset.

    This paper was presented by Dr. Braxton B. Boren at the 137th Convention of the Audio Engineering Society (AES). More information on this paper can be found on its AES page.

  7. A New Approach to Impulse Response Measurements at High Sampling Rates
  8. For some applications such as binaural 3D audio, impulse responses (IRs) measured at sampling rates of 96 kHz or higher may be desirable, if not necessary. However, if not properly employed, conventional IR measurement techniques at these higher sampling rates may result in low signal-to-noise ratios (SNRs), undesirable pre-responses (or other processing artifacts), and/or potentially even transducer damage. In this paper, the above challenges are addressed and an iterative measurement procedure is proposed which is experimentally shown to achieve superior results compared to conventional techniques in terms of measured SNR and peak pre-response amplitude.

    This paper was presented by Joseph (Joe) G. Tylka at the 137th Convention of the Audio Engineering Society (AES). More information on this paper can be found on its AES page and the slides used in its presentation can be found here.