BACCH-dSP is a standalone Mac application, at the heart of Theoretica's BACCH4Mac packages, for audiophile-level 3D Audio imaging through loudspeakers and headphones. Its Pro version has advanced tools for 3D audio mixing, production, and sound field navigation.

BACCH-dSP is the most advanced stereo 3D imaging and binaural audio processing tool available today, and is used by

  1. Audiophiles seeking true 3D imaging of existing stereo recordings through 2-channel loudspeaker systems.
  2. Audiophiles wishing to emulate their 2-channel loudspeaker systems over headphones.
  3. Musicians, composers, and audio professionals interested in binaural audio mixing and production.
  4. Researchers, developers, and educators exploring applications of higher-order ambisonics (HOA) at the cutting edge of audio technology.

BACCH-dSP incorporates many techniques, algorithms, and methods that have only recently evolved out of the research laboratory, and allows for the construction and rendering of stereo 3D audio images with breathtaking realism.

It is the result of many years of continuous development by Professor Edgar Choueiri, President of Theoretica Applied Physics and Director of Princeton University’s 3D Audio and Applied Acoustics Laboratory.

BACCH-dSP can be easily configured as a parallel processor for the leading DAW applications (e.g. ProTools, Logic Pro, Ableton Live, etc.) or as a standalone application for processing audio from audio files, and audio from audio file players (Roon, iTunes, JRiver, etc...) and streaming services (Tidal, Spotify, etc...).

The wide functionality of the BACCH-dSP includes the following main features:

  1. Quick and easy design of individualized BACCH® filters for rendering binaural audio (and regular stereo recordings) in full 3D over a pair of loudspeakers.
  2. Quick and easy design of individualized BACCH-hp filters for rendering highly externalized 3D audio from headphones.
  3. Advanced head-tracking for real-time dynamic sweet spot adjustment for seamless 3D audio over a wide range of listener locations.
  4. The powerful BACCH-3dm mixer for precise mixing of audio sources in 3D space.
  5. Quick and intuitive design of 3D trajectories for moving sources in 3D space.
  6. Extensive automation integration with the leading DAWs.
  7. Powerful Higher-Order-Ambisonics-to-binaural rendering and 3D soundfield navigation.
  8. 2-band and 3-band crossover network with 2nd and 4th order Linkwitz-Riley filters.
  9. Diagnostics and measurement tools for binaural audio.
  10. The most advanced room correction technology available today.
BACCH® 3D Sound

(Available in the Audiophile, Audiophile+ and Pro editions)

A main feature of BACCH-dSP is BACCH 3D Sound, which is an advanced patented crosstalk cancellation technology, developed at Princeton University, that yields vivid and accurate 3D imaging from binaural (and regular stereo) audio over loudspeakers. This is the same technology at the heart of Theoretica’s highly acclaimed high-end audio processor, the BACCH-SP.

Unlike other crosstalk cancellation technologies, BACCH® 3D Sound produces no tonal distortion and can be individualized to the listener’s head and ear shape, the particular response of the loudspeakers and the loudspeakers/listening configuration through a quick and easy calibration using the in-ear BACCH-BM binaural microphone.

3D audio through loudspeakers is no longer confined to a tight listening sweet spot. BACCH-dSP’s state-of-the-art head-tracking technology assures real-time dynamic sweet spot adjustment for seamless 3D audio over a wide range of listener locations.

The advanced panel of BACCH-dSP allows further tailoring and optimization of the resulting BACCH filters

To learn more about BACCH® 3D Sound see our FAQ page and the press reviews.


(Available in the Audiophile+ and Pro editions)

The BACCH-dSP is the first product to use the newly developed BACCH-hp headphones technology, which resulted from a 4-year research project at Princeton University.

BACCH-hp filters, produced easily with the BACCH-dSP application, allow binaural audio to be reproduced through headphones with the following main features:

  1. The 3D image is much more fully head-externalized than regular binaural audio.
  2. Unlike regular binaural audio, head-externalization with BACCH-hp works equally well for all listeners.
  3. Rotational head tracking allows fixing the 3D image in space which is critical for enhancing the perception of a realistic audio image outside the head.
  4. Advanced equalization using the in-ear BACCH-BM binaural mic allows optimizing the sound of any headphones for BACCH-hp.

(Available in the Pro edition)

A central feature of BACCH-dSP is its powerful and intuitive 3D mixer: BACCH-3dm.

BACCH-3dm produces vivid and realistic binaural mixes (equivalent to binaural recordings produced through dummy heads or humans with in-ear microphones) from a collection of multiple audio sources such as the tracks of a multi-track recording.

BACCH-3dm’s visually striking graphical interface allows positioning multiple sound sources (each corresponding to a bus line from your DAW, a microphone signal, an audio file or a track from a multi-track file) precisely in 3D space. BACCH-3dm has the following additional features:

  1. A large library of human and dummy head HRTFs.
  2. Ability to load individualized HRTFs with conversion from the regular SOFA format.
  3. Accurate real-time early reflections and reverb calculations based on user-controlled room geometry and a wide range of wall materials.
  4. Real-time six-degrees-of-freedom (X, Y, Z, Pitch, Yaw and Roll) navigation of the 3D soundfield using the keyboard or a Playstation controller.
  5. Synchronized output recording with multi-track file playback for producing final binaural mixes with or without BACCH and BACCH-HP filters.
  6. Presets for down-mixing multi-channel Surrond Sound (e.g. decoded Dolby or DTS) for various speaker configurations (5.1, 7.1, Dolby Atmos 5.1.4 and 7.1.4,and Auro 3D 11.1) to binaural audio for Surround Sound emulation over two loudspeakers using the BACCH 3D Sound module.
BACCH-hoa (main module)

(Available in Pro edition)

The powerful BACCH-hoa module allows for up-to-fourth-order High-Order-Ambisonics-to-binaural rendering and 3D soundfield navigation using up to 20-speaker full dodecahedron virtual speaker system (in BACCH-3dm) and individualized HRTFs.

The BACCH-hoa module has the following main features:

  1. Support for HOA mics with up to 32 capsules (e.g. the em-32 Eigenmike)
  2. 32-channel HOA Recoroder and Player
  3. Up-to-4th-order Ambisonics decoding to uniform virtual loudspeaker spherical arrays
  4. Binaural rendering with individualized HRTFs and 6-degree-of-freedom navigation of the rendered 3D soundfield.
The hs^3 and sme sub-modules of BACCH-hoa

(Available in Pro edition)

BACCH-dSP 9.5 adds two sub-modules to the BACCH-hoa main module: BACCH-hs^3 and BACCH-sme.

I. The BACCH-hs^3 (head-steered sound spotlight) sub-module features a new ground-breaking technology that relies an HOA microphone to create a "high-order beam" that can be steered anywhere in 3D space (using the BACCH-HT-Nav module described below) by simply looking in that direction, to significantly isolate sound sources in the beam from the background.

The BACCH-hs^3 sub-module has the following main features:

  1. Selectable HOA beam pattern, up to 4-th order hypercardiod, that allows up to 16 dB isolation from the background.
  2. Accurate 3D head-tracked steering through the BACCH-HT-Nav module using virtually any regular webcam or infrared Track IR headtracking hardware.
  3. Low-latency binaural rendering through 3D through headphones or earphones (ideally, capable of noise cancellation ) or BACCH-filtered 2-loudpseakers.

II. The BACCH-sme (stereo mic emulation) sub-module allows the accurate emulation of a variable-pattern pair of stereo mics for recording (or low-latency live monitoring) using a single HOA mic.

The BACCH-sme sub-module has the following main features:

  1. 14 selectable beam patterns (omni, and 1st, 2nd, 3rd and 4th-order cardioid, supercardioid, and hyeprcardiod), for each mic in the stereo pair.
  2. Beam steering in 3D, manually or through the BACCH-HT-Nav module using virtually any regular webcam or infrared Track IR headtracking hardware.
  3. Presets for emulation of "XY", Blumlein, and "MS" stereo pair of microsphones.

(Available in the Intro, Audiophile, Audiophile+ and Pro editions)

Starting with version 6.0, BACCH-dSP includes the new u-BACCH module (which is the sole module in the BACCH4Mac Intro Edition). The u-BACCH module (where the “u” stands for universal) produces u-BACCH filters, which give 3D sound over loudspakers (with no head tracking) based on the user's input of quick tape measurements of the listening geometry.

u-BACCH filters come close to the performance of regular BACCH filters (the latter rely on acoustic measurements using the BACCH-BM in-ear mic) if the loudspeakers are well-matched in frequency and phase.

The u-BACCH module has the following features:

  1. Only requires the user to enter two measurements: the distance between the symmetrically placed speakers, and that between the speakers and the listener's head, in cm or inches, using a measuring tape. No need for acoustic measurements with a binaural mic.
  2. Uses the same HRTF-based filter design code as regular BACCH filters.
  3. Handles and applies u-BACCH filters the same way as regular BACCH filters.
  4. Provides an entry-level view into the world of BACCH.
3D Trajectory Designer

(Available in the Pro edition)

This new module, first introduced in BACCH-dSP 8.0, allows binaural content creators (e.g. mixing engineers, musicians, composers, AR/VR audio designers) to easily and intuitively design/draw complex trajectories in 3D space for the sources in the 3D mixer to follow.

The 3D Trajectory Designer module has the following main features:

  1. An easy-to-use and intuitive interface allows drawing simple or complex 3D trajectories in the 3dm mixer by hand or by precise 3D positioning of anchor points on the trajectory.
  2. The speed of each source as it moves on a given 3D trajectory can be precisely controlled and the motion can be automated.
  3. Automation of the motion of any of the 20 sources along drawn trajectories can be transmitted to any of the leading DAWs (e.g. ProTools, Logic Pro, Ableton Live), where it can be recorded, edited, and sent back to the 3dm mixer for playback.
  4. Even the head of the "listener" can be made to move along a 3D trajectory, and its six degrees of freedom (x,y,z, pitch, yaw and roll) can be automated from the DAW.

(Available in the Pro edition)

Starting with version 8.2, BACCH-dSP includes the new HT-Nav module which allows 6 DOF navigation of the 3D soundfield in BACCH-3dm to be done naturally and intuitively using virtually any regular webcam or the infrared Track IR headtracking hardware) . Simply move your head in any of the 6 degrees of freedom and watch the dummy head in BACCH-3dm mimic every movement in real time, producing the HRTF-filtered binaural audio that corresponds exactly to that 3D perspective.

The HT-Nav module has the following features:

  1. Perfect real time navigation of the 3D soundfield by simple movements of the user's head in 6 DOF.
  2. Motion amplification (or attenuation) by up to x2 in any of the 6 DOF, e.g. move (rotate) your head by 1 meter (25 degrees) to navigate 2 meters (rotate 50 degrees) in the soundfield.

(Available in the Intro, Audiophile, Audiophile+ and Pro editions)

The BACCH-Xover module allows the user to quickly design a crossover network through an intuitive graphical interface.

The BACCH-Xover module has the following main features:

  1. 2-band or 3-band crossover network options for bi-amping or tri-amping applications.
  2. 2nd or 4th order high-precision (64-bit) Linkwitz-Riley filters.
  3. Adjustable delay time for each band up to 1 ms.

(Available as an optional module in the Audiophile, Audiophile+ and Pro edition)

BACCH-ORC† is the most advanced room correction technology today. Unlike any other commercially available room correction system, BACCH-ORC relies on quick in-ear (binaural) acoustic measurements, millimeter-resolution head tracking, and cutting-edge algorithms derived from years of psychoacoustic research, to produce and apply individualized optimal room correction (ORC) filters that elevate any stereo loudspeaker playback system to its ultimate level of transparency.

Not only does BACCH-ORC correct for the spectral coloration of the loudspeakers and the listening room, it also neutralizes the spatial signature of the loudspeakers, which interferes with the spatial cues of the sources in the recording, leading to significantly enhanced spatial imaging.

Click here to learn more about BACCH-ORC.
BACCH-ORC is now available for $1000 as an optional module of BACCH-dSP 14 (Audiophile Edition and above), the application at the heart of Theoretica's BACCH4Mac products, released on February 16, 2024. However, to mark the launch of the new technology, we are offering a free perpetual license for BACCH-ORC with any purchase of BACCH4Mac Audiophile (and higher edition levels) made by March 3, 2024. Current owners of a licensed copy of BACCH-dSP Audiophile (or higher levels) with a valid software update service plan by that date will get a free perpetual license for the BACCH-ORC module, in appreciation of their early adoption of BACCH4Mac.
BACCH-dSP can run under the latest Mac OS, Sonoma 14.2, as well as all previous Mas OS versions down to Mojave 10.14. The head tracking feature works only under the Sonoma, Ventura and Monterey Mac OS (14.x, 13.x and 12.x)
BACCH-dSP is also fully compatible with all Mac computers that can run these operating systems, inlcuding the latest M1 and M2 Macs.
The Release Notes for the latest few versions of BACCH-dSP can be viewed/downloaded as a PDF file from here