Friday, July 13

Via VT1730 & VT 1731 DXD Interface Chip

Via, the Taiwanese company known for producing IC's for the computing industry at highly competitive prices, has announced a DXD compatible set of chips for there new USB Audio Interface generation.

Hopefully this will allow cheap and common consumer goods to support DXD rate PCM, though the quality will have to be evaluated, it is the first step towards broader acceptance of the format.

I missed this when it was announced May 16, 2011, and am not aware of any products currently using it.

Sadly it seems Via, despite low price, do not respond to requests for evaluation kits from individuals. Hopefully this is another step toward common availability of DXD interface for consumers.

USB-Dual-Audio now named UDA, 2 Versions coming.

The USB-Dual-Audio from ElectrArt in Japan is now named the UDA. This will hopefully assist in finding it in searches, USB-Dual-Audio was IMHO too generic a name to yield proper search results.

The Newest release of the UDA mentioned on ElectrArt's website will apparently come in two versions. One called the "DoP" version, supporting the new dCs standard of DSD packed PCM and no recording facility. The other the "standard" version with a proprietary driver, and supporting recording and playback of DSD.
This makes the UDA compatible with many pieces of software, though it seems it can not be upgraded to achieve this functionality, and a new revision of the hardware is required.

There was a board shown giving SDIF support over BNC for interoperability with standard DSD equipment, a big feature. I have been waiting for this for years, and a major plus for studio use.  Hopefully the boards will be available soon, they have been shown for the past 6 months on the ElectrArt blog.

In addition, since the first release (1.0, which is the version I have) the clocks have been replaced with the excellent NDK NZ-series oscillators. The UDA features discrete oscillators, at 22.5792Mhz and 24.5765Mhz, for 44.4khz*X or 48Khz*X, respectively.

Sunday, April 8

The exD interface, The sdtrans384, and the new USB DSD driver standard from dCs.

2012 IS the year of DSD on your PC (or Mac OS X, or *nix)!

There are commercial sources of DSD online, Multiple vendors supporting DSD over USB, mostly thanks to dCs for solidifying a standard way of easily adding cross-platform native DSD support. Plus the sacd-ripper project has created a way to create fair-use bit-perfect backups of your SACD's, allowing the building of music servers or collections of DSD audio, finally with the same freedom we are used to from CD's and DVD-A's. The Korg MR-2 Can be loaded with SACD's now, allowing iPod like freedom with DSD, this has been the last major hurdle to acceptance of DSD on a wider scale IMHO.
The exD Interface has been brought to my attention, available now in 3 versions, a PCM only version, a DXD/PCM version, and a DSD/DXD/PCM version. I have not yet tested this interface, but it seems to support the standard driver model as defined by dCs, allowing a good choice of compatible software.

Chiaki's sdtrans384, the newest incarnation of the legendary sdtrans192, support DSD files at up to DSD256! This is remarkable and makes it the first hobbyist DIY SD-card player capable of high speed DSD. Previously, the only commercial SD card player capable of DSD was the Korg MR-2, but it only supports up to 64fs (2.8Mhz). The sdtrans384has been given high praise in terms of sound quality, indeed the use of an sd card and dedicated hardware for playback is used as a means of minimizing jitter to levels below that obtainable with optical media or most USB interfaces...

The dCs standard for DSD over USB via packing into PCM samples, padded with 8 identifier bits, has seen more acceptance than any other consumer DSD driver model so far, with support from many hardware and software vendors, even across any platform. It does create an stream that must be stripped of the 8 padding bits with minimal jitter, no reports yet on any problems from processing.

 This is just a report on the basic situation, if I missed any software or hardware please contact me and I will list it.

Software supporting the dCs standard:
Hardware supporting the dCs standard:

External Articles on the dCs Standard:
Positive-Feedback: Announcing the DSD Open Standards Movement
The AudioBeat: DSD Over USB: An Open Standard

This site has no affiliation with any vendors mentioned, this information is provided to spread awareness of DSD.

Saturday, March 10

The Open-NGDI Project - Definition Stage

I have started an Open hardware project named the Open-NGDI, or Open Next-Gen Digital Interface. The Goal of this project is to build an interface for connecting modern high dynamic range ADC/DAC's to a personal computer.
We need people like YOU to help define the project in this critical early phase before development starts!

Key Features:
  • Maximum Sample rate is planned to be 512fs (24.576Mhz), at up to 8-bit, capturing what is commonly referred to as Multi-bit Delta-Sigma, or Sigma-DPCM. 
  • Up to 8-Channel's per board is planned @ 512fs, with the capability of expanding channels through syncing of multiple boards. (48bit width I/O @512fs (24.576Mhz), either 6x 8-bit, 8x 6-bit, or 48x 1bit)
  • Support PCM up to 1.5Mhz @ 32 bit depth
  • Modular Architecture - Digital Interface, ADC, DAC, Power Supply, Analog Stages all on separate boards.
  • Open Source Hardware license. All associated software/hardware and documentation will fall under an open source style license. GPL v2 for all software, OSHL v1.0 currently for the hardware license.
  • Community developed and fully documented. An open community will be encouraged.
  • Sister project the Open-NGSDR will be developed side by side with this project, and aims to create a version of the Open-NGDI optimized for SDR and measurement purposes.

Involvement is encouraged by anyone interested.

This project needs YOUR help. 

This project can not get off the ground without a community. 

Even if you have no experience in programming, designing PCB's, or writing VHDL code, you can help by showing support, and giving your idea's, opinions, and criticism.

I have created a Google Code site and a Google Group Site to consolidate information and facilitate starting a community. 

Thursday, February 9

Prototype 1-bit 512fs (24.576Mhz) USB DAC Interface from the 1-bit audio consortium.

I have very exciting news. The 1-bit audio consortium has shown a high speed USB DSD DAC interface, capable of all known standard speeds of Delta Sigma, from 2.8Mhz (64fs or SACD) to 24.576 (512fs). It seems faster than 128fs DSD is finally getting some attention by designers. Hopefully this will mature into some product. Most of these demonstrations over the past few years have been only proof of concepts, such as Korg's 8-channel USB ADC/DAC interface and DAW software shown last year, or previous USB Interfaces shown by the 1-bit audio consortium.

Seeing this being developed shows people are still looking forward with Delta-Sigma for audio. The holy grail of perfect digital audio recording/playback has not been found yet in my opinion.

Link to to referring article: