November 2023

The development of VELVET SOUND

AKM: over 35 years of design and development

History of Asahi Kasei Microdevices Corporation (AKM) D/A Converters

Innovating DACs since 1989

The History of AKM's D/A Converters

Asahi Kasei Microdevices Corporation (AKM) released their first delta-sigma D/A converter (DAC) in 1989. 

The first-generation Premium audio DAC, a multi-bit device based on DWA (Data-Weighted Average) technology, followed in 1998. 

The second generation was launched in 2007, beginning with AKM’s Premium 32-bit DAC.

The VELVET SOUND brand was launched in 2014. 

The third-generation Premium DAC, the VERITA AK4490, was launched. It employs AKM’s enhanced low-distortion technology to achieve 120dB SNR, voltage output performance of -112dB THD+N. 

Further expanding the Premium DAC lineup, the AK445x Series was released, which includes 2-, 4-, 6-, and 8-channel configurations.


D/A Converters


AKM released the AK4497 in 2016, completing the lineup of the third-generation 32-bit premium DAC7 products. Supporting the high-resolution next generation specification, DSD 22.4MHz, AKM also realized the specification of S/N 128dB, THD+N -116dB by employing its in-house high sound quality LSI process.


D/A Converters


In 2019, AKM introduced the VERITA AK4499, current-output DAC. With the newly developed switched resistor analog core, the AK4499 has updated characteristics with S/N 140dB and THD+N -124dB.


D/A Converters


In 2022, AKM introduced the AK4490R and AK4493S, renewed versions of the AK4490 and AK4493. Subsequently, AKM introduced the AK4191 + AK4499EX, a separate digital/analog DAC solution, brushing up the sound quality. 


AK4491 + AK4499EX
DAC solution for a complete separation of digital and analog circuitry.


History of Asahi Kasei Microdevices Corporation (AKM) A/D Converters

Revolutionizing ADCs since 1987

The History of AKM's A/D Converters

Asahi Kasei Microdevices Corporation (AKM) released their first-generation delta-sigma A/D converter (ADC) in 1987.

The fifth generation ADC was launched in 1992.

In 1996, AKM introduced its "2-2 Cascade Connection technology."

 Since then, AKM has consistently provided ADCs with advanced features such as low power consumption, multi-bit delta-sigma modulation, and AKM's original bi-directional DWA (Data Weighted Average) technology. 

AKM has consistently improved conversion resolution, from the first generation of 16-bit devices to 18-, 24-, and now 32-bit ADCs, and has increased sampling frequencies from 48kHz to 768kHz.

The VELVET SOUND brand was launched in 2014.

The first VELVET SOUND product, the flagship VERITA AK5397 ADC, was released with an unmatched SNR of 127dB.


A/D Converters


In 2016, the premium high-end AK557x series and four premium AK555x series were released, each comprising four products. In total, nine products are available in the premium 32-bit ADC lineup.


A/D Converters


History of Automotive Audio Solutions

The History of AKM's D/A Converters

In 2023, Asahi Kasei Microdevices Corporation (AKM) released VELVET SOUND for Cars, a brand of in-vehicle solutions with audio ICs, software algorithms, and tuning.