Author Topic: AK4497 DAC processor / kits  (Read 875 times)

Offline chrisc

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AK4497 DAC processor / kits
« on: February 08, 2017, 08:02:30 AM »

The first description is about the processor itself.  Next are some kits available from eBay.

The processor costs in the region of R950, the kits are about R1300.  You would also need a power supply and an enclosure

The high-end audio market is being driven by the growing availability of high-resolution sound sources. Aasahi Kasei Microdevices Corporation (AKM) has developed a new 3rd generation flagship premium D/A converter, the VERITA AK4497. This is the new, higher performing solution of the VERITA AK4490 that is adopted by many audio products since it was launched in 2014.
The AK4497 is a new generation premium 32-bit DAC based on AKMís VELVET SOUND architecture that has been widely adopted by well-established high-end audio companies. High signal to noise performance is achieved by improving VELVET SOUND technology by supporting a larger current drive capability. The performance of an audio DAC using switched capacitor is expanded to the limit with the AK4497. In addition, AKM has developed an original process that has greatly improved low noise performance and electric margin for audio devices, increasing data amount and enhancing original acoustic sound that can be found in the sound strength.

The AK4497 has been introduced in CES 2016 that is held from 6th Jan. at Las Vegas, NV, USA.
Samples are available from Feb. 2016 and mass production will be available from the summer 2016.

● Dynamic Sound Playback with Large Amount of Playback Information: VELVET SOUND architecture is improved
Not only circuit designing but also the LSI manufacturing process was newly developed at AKM exclusively for AKMís audio devices.  The AK4497 is the first device to utilize this process in AKMs foundry. 32-bit processing is integrated for the IRD (Impulse Response Designed) Filter, reproducing a detailed and natural signal wave. A low-dispersion short delay filter was newly added to the other five filters found in our previous generation device. So, six different digital filter types are selectable according to the user audio and system preferences.

● AKMís Best Performance D/A Converter
Low-distortion technology achieves industryís best performance of -116dB THD+N DAC with 128dB S/N characteristic. The AK4497 has the best performance among AKMís D/A converters. In addition, OSRD (Over Sampling Ratio Doubler) technology greatly reduces out of band noise.

● Supporting High Resolution Data
The first in the industry, a 22.4MHz DSD input is supported. The digital input supports up to 768 kHz PCM and 22.4 MHz DSD (Direct Stream Digital), recreating high-resolution sound that is as close as possible to the original acoustic source.


Flagship Premium D/A Converter
DR, S/N   128dB (Mono mode: 131dB)
THD+N   -116dB
Sampling Rate   8kHz to 768kHz
DSD Input   2.8MHz, 5.6MHz, 11.2MHz, 22.4MHz

Sound Color   Six Types, 32-bit 8-fold Digital Filters
- Short Delay Sharp Roll-off, GD=6.25/fs
- Short Delay Slow Roll-off, GD=5.3/fs
- Sharp Roll-off
- Slow Roll-off
- Super Slow Roll-off
- Low-dispersion Short Delay
Resolution   32-bit
Number of Channel   2ch
VELVET SOUND Technology   Low-distortion technology
OSRD (Over Sampling Ratio Doubler) technology
Power Consumption   346mW
Power Supply   Analog: 4.75 to 5.25V
Digital: 1.7 to 3.6V
Operation Temperature   -40 to 85įC
Package   64-pin TQFP (10mm x 10mm)


There are many, but this is an example on eBay

To me, this sounds like a promising development in the quest for more accurate digital reproduction

Offline pwatts

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Re: AK4497 DAC processor / kits
« Reply #1 on: February 08, 2017, 04:38:42 PM »
Got to say, I doubt the difference between AK4490 and 4497 would be a) achievable and b) audible with basic designs. While chasing numbers are useful for studios and building audio analyzers, for a plain playback DAC built on a budget I would not bite. The extra 3dB or so from dual-mono is especially bound to just get buried under the noisefloor.
ESS says the same about their new ES9038PRO, which is meant for studio use and discrete output stages to coax the last bit of SNR out. For end users they recommend the ES9028PRO or the older 9018.

I would rather take a 4490 at less than half the price and do a proper implementation than shoe-horning two 4497's in this chinese affair.