Sound Philosophy

Sound Philosophy
Real Live Sound

An accurate, "reproduction of the original", is the VELVET SOUND philosophy.
AKM duplicates all sound elements contained in the, "original source".
AKM provides an active space just like a live performance.

The History of AKM's A/D Converters
Since 1987,

AKM released a first generation delta-sigma A/D converter, (ADC), in 1987, and a world class fifth-order delta-sigma A/D converter in 1992.  AKM's quality ADC had piqued attention in the audio industry. "2-2 cascade connection", technology that maximized the ADC performance was introduced in 1996. Since then, AKM has been providing ADCs with world class performance by developing advanced technologies such as low power consumption, multi-bit, and AKM's original bi-directional DWA (Data Weighted Average) technology.  In addition, AKM has been improving the conversion resolution from the first generation of 16-bit to 18, to 24, and now 32-bit, and expanding the sampling frequency from 48kHz up to 768kHz, as a worldwide cutting edge leader of audio capture technology.
 A new generation architecture, the "VELVET SOUND", brand launched in 2014.  As the first product of VELVET SOUND, the flagship VERITA AK5397 with world leading performance of 127dB S/N was released. In 2016, four multi-channel products were added to each premium high-end ADC, the AK557X series and the premium ADC AK555X series.  In total, nine products are available in the 32-bit premium ADC lineup.
AKM products have been widely adopted by well-established companies from high-end to consumer uses around the world due to the advanced solutions AKM provides with many years’ experience.

The History of AKM

Sound Philosophy
Original Sound Recording

"To accurately record all sound elements", is the essence of recordings. AKM aims to realize the following philosophy, "as close to the original as possible = not recognizable as a reproduction", with AKM devices.
High resolution recorded original sound is necessary for, "real live sound", playback.  AKM's next generation A/D converters are ideal for realizing the, "Original Sound Recording". 

Ultimate pure analog, beyond the recorded sound


Design concepts to pursue and achieve
the, "intensity", and the, "amount of information".

the architecture of new generation audio devices.
Velvet Sound’s philosophy is a combination of
measured performance and human listening tests,
because ears will always exceed any test measurement.

"Large Amount of Information and Sound Strength"
Design Concepts to Achieve

As the basic concept to represent all of the elements of sound, such as components of the fundamental wave and harmonics, sound pressure, changes in the time domain, the presence of small signal components, the difference between treble and bass of attenuation, etc., AKM has built a new VELVET SOUND architecture.

Amount of information
Delicate Sound Reproduction thorough Noise Optimization

VELVET SOUND architecture has enabled the expression of elusive sounds by enabling a highly noise-tolerant design.  Verifying and identifying the noise mixing paths from every angle is particularly critical to reducing noise sources required for operation of digital and switching circuits.  Furthermore, not only the signal path line itself, but the internal reference signal and clock that determines the time information are separated through layout isolation to thoroughly eliminate influence by noise.  System noise beyond the audible range also reduces more than 40dB compared with the conventional products simplifying the external circuit design.

Pursuing the, "feeling of sound"
Sound beyond the audible range

Human's audible frequency range is believed from 20Hz to 20kHz, but AKM's next generation products cover up to a 200kHz signal range, enabling the expression of, "feeling sound", beyond the audible range.

VELVET SOUND Core Technology

Core Technology
Technologies representing the, "sound feeling",
exceeds the numbers.

the core technology of AKM's new generation audio devices.
This technology features "low-distortion technology",
and "spurious free technology",
which translates, "sounds into emotions".

"Without Distortion"
Low distortion technology

One of AKM’s prominent analog circuit technologies, low-distortion expertise, has been improved further. -112dB THD+N is realized by suppressing unnecessary discharging that occurs by the switching signals in the analog input sampling circuit. This sampling circuit determines the ADC characteristics.

"Without Unfavorable Tones"
Error Free Technology

AKM's low-power consumption and low-distortion technologies achieve the world's smallest* intermodulation distortion characteristic of 116dB.  In addition to a wide dynamic range of 121dB, (single channel), to 130dB (channel summation mode).  By suppressing unauthentic tones generated by interference of several frequencies included in the actual sound, AKM provides an error free dynamic range, "without unfavorable tones".
* According to our research as of Jul. 2016.


Key Features
Fully compatible with, "Hi-Res", sound sources
up to 768k PCM and 11.2M DSD.

a key feature of AKM’s next generation audio devices
which are equipped with specs and performance
for the, "Hi-Res", digital audio era.

"Ultimate analog, natural sound"
Full support of High-resolution audio sources

AKM’s next generation A/D converter adopts 32-bit resolution and supports digital recording up to 768kHz PCM and 11.2MHz DSD to realize the, "ultimate analog, natural sound".  AKM leads the competition for supporting high-resolution audio sources.

Sound Color Digital Filter
Sound Color Digital Filter(SCDF)

Focusing on the waveform in the time domain, the built-in 32-bit, 8x digital filter, controls the transient response of the signal. 5 types of digital filters allow music playback in a variety of sound settings by switching the filter type.

Sound Color Digital Filter

Premium A/D Converters

Product Portfolio

Product Portfolio -Premium ADCs -

* Bubble Size = "Sound Quality"

Premium ADCs

AKM releases the new flagship, "VERITA", AK5397, which achieves the world highest level 127dB SNR.
AKM has released four multi-channel ADCs to each high-end ADC AK557X series and ADC AK555X series. In total nine products are available as in the 32-bit premium ADC lineup.
An extensive lineup will cover a wide range of applications, from high-end to mid-range audio systems.

VELVET SOUND AKM Pursues Real Live Sound with both Roomy Sound & Sound Dynamics