Eilex Audio Technologies

In addition to its primary PRISM™ and VIR Filter™ technologies, Eilex provides an entire family of related audio processes for optimizing the audio experience across a wide variety of systems. For high-end systems, small consumer systems, economy earphones, active speakers, even automotive environments — Eilex has processes which can bring the listener the best possible sound.

Eilex HD Remaster…

High-Resolution Audio Real-Time Remastering

  • 88.2/96/176.4/192 KHz
  • 24/32 Bit
  • Ultra-High Performance Even Order Harmonics Generator
  • Real-Time Operation
  • Extremely Small Computation Requirement
  • CD/DVD/BD Players, TV, Car Audio, Digital Radio

Eilex HD Remaster converts up-sampled (such as 88.2/96/176.4/192 KHz) audio source to Hi-Res audio in real-time. It works on radios and TVs as well as CD and DVD. Read More

Eilex Binaural…

Binauralize Standard Stereo Source in Real-Time

  • Natural Headphone/Earphone Sound
  • Proprietary HRTF
  • Precise FIR Filtering of HRTF and Middle-Ear Frequency Response
  • Minimum Fatigue for Extended Listening
  • Applicable on All Headphones/Earphones
  • Preservation of Headphones/Earphones Tone Character
  • Proprietary APVD (Acoustic Power Volume Density) Measurements

Eilex Binaural is a process which converts recorded materials intended for stereo speakers to Binaural Audio ideal for reproduction with headphones/earphones. It maximizes the performance of any headphones/earphones while maintaining their tonal characters. Read more

Eilex PRISM SoundSpace

2-Channel 3D Sound

  • Proprietary SHM (Spherical Head Model)(1) Modeling
  • Proprietary XTC (Crosstalk Cancellation)(2) Process
  • Natural 3D Sound
  • True to the Original Sound Image and Presence
  • Solid and Steady Dialogue
  • For TV, Laptops, PC Monitors, Mobile Phones

Eilex PRISM SoundSpace is a 2-channel 3D sound process, which consists of Eilex PRISMTM APVD (Acoustic Power Volume Density) equalization technology and Eilex’ proprietary 3D Sound process. It produces a natural 3D sound image and comfortable ambience through a typical 2-ch TV sound system or stereo system. (Note: Eilex PRISM SoundSpace constructs the frontal 3D sound stage. It is not a surround process.)

Today’s thinner, design-oriented TVs have poor acoustics which result in poor sound performance if left uncorrected. Eilex PRISM greatly improves sound quality, while the 3D sound process recovers lost ambience and presence. (Note: See Eilex PRISM white paper for more details of PRISM technology.)

Eilex PRISM SoundSpace adds psycho-acoustic width, height and depth beyond the limited physical spacing of the L and R speakers. Eilex 3D Sound is a linear process that inherently preserves the correct directionality and musicality of the source material.

The 3D Sound process utilizes proprietary SHM (Spherical Head Model) modeling to provide the best possible 3D effect and audio fidelity to all listeners with different head shapes. SHM is more versatile than HRTF (Head Related Transfer Function) which relates to the dummy head used for the measurement.

It is noteworthy that while Eilex 3D Sound widens the stereo image, it keeps monaural sources centered.

Eilex PRISM SoundSpace is compatible with all TV programs including news, drama, movies, music and sports. There is no need to switch sound modes each time the program changes.

Eilex PRISM SoundSpace elevates the sound image to its proper height when speakers are placed below the picture.

Eilex PRISM SoundSpace takes a 2-ch stereo source, unlike virtual surround processes which require digitally connected 5.1-ch signals to operate.

Eilex MaxWide

Wide Sound Stage Headphone Audio

  • Creates Theater Sound from Regular Stereo Source
  • Equalization by VIR Filter
  • Compatible with all Headphones and Earphones

Nearly all media are intended to be reproduced by speakers. However, when played back using headphones/earphones, the sound stage becomes narrower which spoils the enjoyment of action movies and music concerts. Eilex MaxWide widens the sound as if the listener is sitting in the movie theater or concert hall.

Eilex MaxWide creates sound stages of different sizes by changing its parameters. By preparing several different sizes, the user can select the most suitable mode for the program.

Eilex MaxWide is applicable for all headphone and earphone audio, including high-end headphones, smartphones, tablets and TV headphones.

Eilex Harmony

Sound Restoration of Digitally Compressed Audio

  • MP3, AAC (and All “Lossy” Digital Compression) Sound Restoration

The Eilex Harmony improves digitally compressed audio, such as MP3 and AAC, by restoring and enhancing the harmonics lost through compression. Eilex Harmony works by re-generating harmonics from the source material, recovering warmth, details and nuance.

Eilex Harmony works in time domain and requires extremely small computation power.

Eilex Focus

In-Band Harmonics Generator

The Eilex Focus improves digitally compressed audio, such as MP3 and AAC, by restoring and enhancing the harmonics lost through compression. Eilex Focus works by re-generating harmonics from the source material, recovering warmth, intelligibility, details and nuance.

Eilex Focus is most effective if used prior to a Hi-Res conversion.

Eilex Focus works in time domain and requires extremely small computation power.

Eilex PRISM Auto-Bass

Adaptive Bass Boost

  • Automatically Compensates Weaker Bass at Low Volume Level
  • Holds the Maximum Swing within a Safe Zone at High Volume
  • Suitable for Small Audio and TV

Even a perfect recording played back on a high-end audio system will lack bass at low volume levels. This academically-proven phenomenon is often experienced when we listen to music at a low volume. To solve this problem a low frequency compensation technology called “Loudness Control” was developed in 1970’s. It was based on the Fletcher-Munson equal loudness curve and became a feature on consumer audio products, but died out due to disappointing performance. A couple of reasons of the failure were: (1) the wrong compensation curves were used [1] and (2) a lack of adaptive operation linked with actual playback loudness.[2]

Eilex Auto-Bass has been developed based on current psycho-acoustic science and the latest digital audio processing technologies. It compensates for missing bass at the correct range with the correct amount of boost, working adaptively according to the playback level.

It is ideal to use the Eilex PRISM APVD (Acoustic Power Volume Density) equalization and the Auto-Bass process, which maintains bass levels even as the volume is turned down. It is essential to have a flat APVD frequency response of the system, as in the natural world, when applying Auto-Bass. PRISM equalization achieves near-ideal acoustic power frequency response for the playback system at normal loudness.

Eilex Auto-Bass is designed to reproduce recorded materials which are typically monitored at about 80-Phon at the mastering studio. It boosts bass range of low-level playback, such as late night and background music. During louder playback it constrains the bass amplitude within a safe range to avoid speaker distortion and amplifier saturation.

[1] The equal loudness curves themselves were used as the compensation curves, instead of the differences between the curves.
[2] User could only turn Loudness Control ON or OFF. No continuous (or seamless) compensation control against the actual playback loudness was offered.

Eilex PRISM Auto-Volume

Dynamic Range Compressor

  • Reduce Volume Level of CM
  • Increase Very Low Level Sound to Audible Level
  • Increased Maximum Volume
  • Suitable for Small Audio System and TV

Eilex PRISM Auto-Volume maintains any desired volume level for TV viewing, attenuating loud commercials and avoiding the need for volume adjustment between programs. Loud action sequences in movies and TV dramas are controlled while whispering conversations are amplified to provide consistent loudness—all without losing the artist’s intentions. The difference between the levels of TV and Blu-Ray/DVD is also narrowed, reducing the need for volume adjustment between devices.

Conventional auto-volume processes were simple to implement, but they had weak performance and noticeable artifacts. This is especially true of one- or two-band processes with short attack-time and extremely long release-time, which exhibit noticeable breathing and instability.

Eilex Auto-Volume is a three-band compressor based high-performance auto-volume. Normally, compressor-based AGC (Automatic Gain Control) or DRC (Dynamic Range Compressor) has a relatively larger process size which prohibits application to consumer products. By optimizing the process to mere 20MIPS, Eilex Auto-Volume’s process is small enough for implementation in consumer products.

Eilex Auto-Volume consists of the Eilex XERO “Acoustic Power Density Equalization” process and the 3-band compressor-based Auto-Volume process. It is essential to have a flat acoustic power frequency response of the system, as in the natural world, when applying Auto-Volume. XERO equalization helps to achieve ideal acoustic power frequency response.

Eilex Auto-Volume lets users to watch programs at a consistent volume level by automatically reducing the loud sound and boosting the soft sound, without frequently adjusting the volume control.

Eilex Auto-Volume is effective for increasing the maximum volume level of small audio systems where louder sound is desired, such as personal audio and laptop PC, even if sacrificing some dynamic range.

Eilex PRISM Dialogue

Dialogue Enhancer for TV Applications

  • Natural and High Intelligibility Dialogue
  • Solid Center Localization by Psycho-Acoustic Process
  • Maintains the Correct Stereo Image
  • Suitable for TV with Down-firing Speakers
  • Proprietary HRTF Improves Vocal Intelligibility
  • Lift the dialogue to the TV picture level

The latest design-oriented flat-panel TVs have down-firing, side-firing or even back-firing speakers—very different from the ideal front-firing layout. Naturally, the acoustic condition of these configurations is inferior and the sound quality is poor. The intelligibility of speech is especially deteriorated. Since speech is the most important part of TV audio, inferior speech intelligibility may damage the value of the TV. Eilex PRISM Dialogue dramatically improves the clarity and intelligibility of speech.

PRISM Dialogue consists of the PRISM Acoustic Power Volume Density equalizer and the Dialogue Process. It has been developed based on current psycho-acoustic science and the latest digital audio processing technologies.

The psycho-acoustic technique applied to the Dialogue process suppresses the uncontrolled stereo image caused by the abnormal speaker settings, while enhancing the dialogue.

It is essential to have a flat acoustic power frequency response, as in the natural world, when applying the Dialogue process. PRISM equalization achieves ideal acoustic power frequency response. (Note: See PRISM white paper for more details of PRISM technology.) Proprietary HRTF is used to achieve ideal frequency response, maximizing speech intelligibility. It also raises the sound image to picture level; otherwise voices are heard from below the picture. The HRTF process is executed by a VIR filter which provides maximum precision and accuracy.