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Home Mobile Apps (iOS) iPhone - Ambiophonic Audio Player

Ambiophonic Audio Player for the iPhone



The application has been replaced with the new solution provided by our startup

Please visit the AMTRA Play (iOS iPhone & iPAD) product page:






The Application implements Recursive Ambiophonics Crosstalk Elimination for audio reproduction.


Don't use Earphones!
You need to connect loudspeaker - closely separated - to experience Ambiophonics!

The Principles of Ambiophonics:
1.) Ambiophonics uses "Recursive Ambiophonic Crosstalk Elimination" to enable binaural listening
2.) The Speakers are positioned with a separation angle smaller than 20° (called Ambiodipol) instead of 60° used in stereo. No worries, in contrast to stereo, the sound stage goes far beyond the boundaries set by the speakers (up to 120°).

1.) Ambiophonics has been invented by the Ambiophonics Institute:
2.) RACE (Recursive Ambiophonic Crosstalk Elimination) is a free algorithm made available by the Ambiophonics Institute.

Listening Experience:
The sound stage gets a strong deepness, height and wideness which creates a real three dimensional listening experience.
Locating a single sound source within the original stereo image is much easier with Ambiophonics. You're able to pinpoint each instrument in all three dimensions!
To achieve optimal cross talk cancellation Ambiophonics has a sweet spot (similar to stereo) along the median line where the sound stage has its best representation.

Key advantages in comparison to stereo:
1.) Elimination of Comb filtering effects and pinna direction finding errors.
2.) By having the speakers close together reflections by walls and the bass mode response of the room are much easier to control.
3.) The center presence is very stable and therefore always easy to locate.

Which records sound best?
In contrast to the standard stereo setup where spatially rich recordings that contain binaural cues with inter-aural time differences (ITD) loose their deepness, Ambiophonic plays back a much richer sound stage.
Many productions mix monaural microphones or direct sources between channels to create phantom images limited to inter-aural level differences (ILD), but even those recordings do get a wider and more precise sound stage with Ambiophonics.

Setting up your listening environment:
1.) Place your speakers in a separation angle of around 20°. The speakers do need a good phase response, but even simple single driver PC-Speaker work well.
2.) Set the application parameter to the following values:
- Race Attenuation: 2.2 dB (Defines the amplitude of the cancellation wave front)
- Center: 0 % (Sets the center presence)
- Delay: 68 micro seconds (Depends on the speaker separation angle)
- Leveling: -6 dB (Output attenuation to prevent digital overs caused by the Ambiophonic algorithm)
- Auto Leveling: ON (Automatic attenuation to prevent digital overs)
- Frequency Limited RACE (0-4.5kHz): OFF (Applies Ambiophonics to a limited frequency range)
- Bypass: OFF (Allows the comparison between Ambiophonics and Stereo)
3.) Select a track from the iPod library
4.) Move along the median of the speakers until you find the best sound stage experience
5.) Adjust the parameter to match your listening environment

Technical Specification:
- 32Bit Digital Signal Processing
- Playback of none DRM-Protected audio files of the format 16Bit / 44.1kHz