The Well-Tempered Computer, an introduction to computer audio

Thursday, June 30, 2011


Saturday, June 25, 2011

Antelope Isochrone 10M Rubidium Atomic Clock

Antelope Audio, makers of the Zodiac DAC range, also specializes in audio control clocking devices.  Its Isochrone 10M is a Rubidium Atomic Reference Generator based on real atomic technology that is a staggering 100,000 times more accurate than the quartz oscillators used in most audio equipment. The 10M is designed primarily for studio use but will also appeals to computer audiophiles who just will not live with clock induced jitters.

  • Swiss-made Rubidium core with accuracy of 0.03 parts per billion
  • Ultra-precise Atomic oscillator with stability of 1 second in 1,000 years
  • Rubidium core is FEI 5660 Compatible Stanford PRS10 Equivalent
  • Dual Redundant power supply with automatic switchover
  • 8 BNC outputs of 10 MHz
  • Compatible with any device that accepts 10 MHz reference
  • Utmost ease of operation, just connect it and power it on
  • Extremely sturdy mechanical construction
  • Perfect match for OCX, OCX-V and Trinity
  • US$5,995

Wednesday, June 22, 2011


TEAC (originally "Tokyo Electro Acoustic Company") has been making fine consumer electronics since the 1950s under its own trade name and its other two subsidiary TASCAM and ESOTERIC. The first one focuses on pro-audio, and the latter in ultra hi-end audio. As we all aware, Esoteric's digital audio products are considered among the best in the industry. Their VRDS transport mechanics are unsurpassed. Their digital to analog converters are known to up there with the state of the art.  

Vincent Kars hinted us that TEAC, the mother ship, has quietly launched (in Japan and Europe) the new UD-H01 DAC with USB input and a built in headphone amplifier. Using two 32 Bit 192kHz Burr Brown converters, the DAC upsamples data to 192kHz. It has coaxial and optical inputs and both XLR and RCA outputs. Due to be available in July for £299.  Also launching together is an AirPlay adapter that will enable you to transform your existing HiFi into an AirPlay compatible device, also for £299.  This DAC looks almost too good to be true in terms of specs and build quality versus price.

  • USB Audio Class2 High-speed Input from PC/MAC (using the Tenor 8802 chip)
  • 32-bit/192kHz Dual D/A Convertors (BurrBrown 1795 x 2)
  • Up-conversion to 32bit/192kHz
  • Supports full speed Asynchronous Transfer Mode (to be confirmed, we suspect with drivers)
  • Toroidal-core-Power Transformer
  • Detachable AC Socket
  • Headphone Out with Volume Control
  • Aluminium Front Panel
  • USB Input: x 1 (USB2.0)
  • Digital Audio Inputs: x 2 (Coaxial, Optical)
  • Balanced Audio Output: x 1 (XLR, 1-GND, 2=Hot, 3=Cold)
  • Audio Output: x 1 (RCA)
  • Headphone Out: x 1 (6.3mm)
  • Input Signal Sampling Rate: 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz, 192kHz
  • Dimensions (W x H x D): 215mm x 55mm x 215mm

Tuesday, June 21, 2011

Audiophile Sympathy Cards

ASUS Xonar Essence One USB DAC and Headphone Amp

ASUS, the computer giant, launched a digital audio line under trade name Xonar.  Their first product, the Essence One, is a headphone amp / DAC with USB and SPDIF inputs.  Utilizing a PCM1795 32-bit DAC chip which upsamples everything to 384kHz.  RCA and balance XLR outputs.

Friday, June 17, 2011

Interger mode explained

Damien Plisson, developer of Audirvana OSX music player software,  has published a white paper (in conjunction with AMR Audio of UK) explaining the importance of player software and Mac's playback Integer Mode.  As of writing, only Audirvana and PureMusic v.1.8 offer such capabilities with compatible DACs.

In computer audio, the player software replaces the CD drive as the transport feeding the DAC. Ensuring bit‐perfect output of the original audio signal is a pre‐requisite, while minimizing jitter and RF interferences are still strongly needed. This paper explains the main factors impacting sound quality on the computer side, and the means that have been implemented in Audirvana player and the AMR DP‐777 DAC to boost the audio experience to the next level above the normal iTunes. These main means are bit-perfect, sample rate switching, asynchronous transfer and Integer Mode.
The white paper can be downloaded here.

Wednesday, June 15, 2011

Widealab Aurender Digital Music Player

Widealab of South Korea announced the launch of their Aurender Series Digital Music Storage and Playback Systems with Solid State Drive Playback and iPad user interface. Solid State Drives have numerous advantages over CD mechanisms and hard disk drives which have mechanical parts that wear down and emit noise. More importantly, there are limitations to accurately reading and playing back data from a spinning disk in real time. Solid State Drives have no disks, almost no seek times and vastly lower random access times than hard disk drives and compact disk drives. This ensures absolute accuracy in reading and playback of music files.
Another vital factor in flawless playback is the accuracy of the clocks which are used as references in reading and playing back music data. Aurender's clocks are based on ultra-stable TCXO or OCXO oscillators, depending on the model. The next step up in performance to OCXO oscillators are rubidium oscillators which are used in atomic clocks. The OCXO oscillators used in the Aurender are of the finest quality and boast an accuracy under 5 billionth of a second. TCXO and OCXO based clocks along with proprietary re-clocking using Field Programmable Gate Arrays guarantee that the signal to the Digital Analog Converter is as accurate as possible. 

The Aurender can store up to 6 terabytes of music in uncompressed or lossless formats which are used by studios and broadcasting companies to archive their recordings. The iPad is the user interface for the Aurender Music System and the application is free of charge. By using the iPad as an interface, users can easily view all details of the music collection according to Song, Artist, Genre,Album, Composer and Conductor, in addition to instantly selecting songs and editing playlists.

All models are designed to be used with high quality DACs and have AES/EBU, Coaxial and Optical outputs. The S30 model offers an IIS connection and the R10 model has a digital I/O for master clock (10Mhz). Other features include Linux OS customized for audio applications, uncompressed and lossless formats, up to 24 bit/192 kHz resolution, fanless design and precision machined aluminum case and parts designed to protect sensitive components from electromagnetic noise and vibrations. In addition, the Aurender has LAN and USB connections for transfer of music files from external storage devices or PCs.

Expected retail prices are $4,600 for the Aurender A10 and $5,700 for the Aurender S10.

Aurender Brochure

Tuesday, June 14, 2011

Stello U3 USB to SPDIF converter

Stello of South Korea has launched its successor to its successful U2 DDC (digital to digital converter) with the new Stello U3 192/24 USB Link.  The unit is based on the now-industry-standard XMOS chip which is capable of high speed (24/192kHz) asynchronous USB transfers.  Galvanically isolated SPDIF outputs (coaxial and AES/EBU).

  • USB Audio Class 2.0 compliant Asynchronous synchronization mode 
  • High Speed Bit Perfect Audio Data Stream up to 192kHz sampling rates
  • Master clock Super low jitter 2 external clocks
  • Sampling Frequency 22.5792mHz/24.576mHz for multiples of 44.1kHz/48kHz sampling rates
  • Resolution Standard sample rates 44.1, 88.2, 176.4, 48, 96, 192kHz/24bits Audio
  • Input 1 USB 2.0, Type B connector
  • Outputs Galvanic Isolated, Up to 192kHz sampling rates
  • 1 COAX 75 Ohms, Gold Plated RCA Connector
  • 1 AES/EBU 110 Ohms, Neutrik XLR Gold plated contacts
  • Lock indicator LED on the front panel
  • Platform Support Customized Windows Driver : Windows XP, Windows Vista, Windows 7
  • Natively supported by Apple Mac OS X
  • Dimension 100 X 36 X 100mm (WHD)

Meitner Audio MA-1 DAC

Ed Meitner's new company Meitner Audio first product is a 24/192khz MA-1 Stereo DAC which will be available for US$6,750 which is way lower than his previous creations at EMM Labs.  

The Meitner MA-1 supports sampling rates from 44.1 to 192 kHz at word lengths up to 24 bits through all six digital inputs and it complies with the USB Class 2 audio interface standard.  MFAST (Meitner Frequency Acquisition System) high-speed asynchronous technology decouples input from output.

Meitner Digital Audio Translator (MDAT) upsamples digital audio to 5.6 MHz (double the SACD standard sampling rate). Standard-setting MDAC dual differential discrete D-to-A (not based on generic OEM D/A chip), and MCLK high-purity master clock modules are included in this design. Digital inputs include USB, AES/EBU via XLR, two optical TosLink, and two S/PDIF on RCA jacks. Stereo analog outputs include stereo balanced via XLR and unbalanced via RCA.

Monday, June 13, 2011

BO.01 REBRAUN music server

Came across this re-worked vintage B&O Braun by Bootleg Objects.  Intended as an art piece, but nevertheless interesting.

Vintage case, digital data, mixed multimedia, aluminium, acrylic, steel, liquidcrystal. CNC-milled, welded, thermoformed, lacquered, anodized.Programmed with the VVVV MULTIPURPOSE TOOLKIT.DIMENSIONS (WxHxD): 650x120x280mm

12000 EUR purchasing information

Designed in 1962 by Dieter Rams, the “Audio 1 Kompaktanlage” is a milestone of german post-war design. It embodies, even more than its predecessor, the famous “snow-white’s coffin”, the design ideals of the rationalist “Ulm School”. These sober paradigms of utility and matter-of-factness are playfully remodelled in the “ReBraun”: Two TFT-Displays take the place of the radio scales, the lettering on the anodised front plate ironically quotes the lingo of the radio era. A randomly positioned button, labelled “Zufall” (Randomness) stands for the freedom from mechanical constraints. The antenna does not receive any FM radio, but is used to connect the system to the internet via Wireless LAN. The case and acrylic hood were lowered by several centimetres for sporty reasons (think: hot rod!), and the window that formerly contained a signal strength readout now becomes a tabernacle for the old Braun nameplate.

Hifi Choice reviews the M2Tech Young DAC

HifiChoice/TechRadar has published reviews of the M2Tech Young DAC (earlier reviewed by us).  Some excerpts...
"The first thing to make clear is that the sound is certainly of high-end breeding. We would have been most disappointed had it lacked anything significant in terms of resolution or neutrality and, indeed, it scored highly for both of those. 
It's actually exceptionally revealing and brought out details we had forgotten about in some of our own recordings – things we remembered from the recording session but hadn't heard in a while via more prosaic replay equipment.
If we have any criticism, it's of the very low bass. Now and then, in recordings which really plumb the depths, we were convinced we missed just a little clarity of pitch in the bass. There's plenty of impact, and extension, as such, is pretty much peerless, but tuned low frequencies (church organ, upright bass, orchestral timpani and so on) don't always quite seem as certain of their tuning as can sometimes be the case."

Thursday, June 9, 2011

Cambridge Audio 751BD Blu-Ray Universal Player

UK's Cambridge Audio announces the successor to its successful Azur 650BD, and the only challenger in town to the throne of universal players currently reign supreme by Oppo 93 and 95, with the new Azur 751BD Blu-ray Universal Player.  In addition to playing any disc known to man, the unit features high quality audio and video decoding.  Using the supplied wireless dongle and any UpNP server, (PC w/Media 7, Apple with Twonky, EyE Connect, or NAS Drive) you can stream your entire music library into the Azur 751BD using exclusive Anagram Q5 up-sampling to get REAL 24-bit native performance without any wires. 

  • Formats decoded: Blu-Ray / BD-3D / DVD Video / Audio / DVD-R/RW / SACD / HDCD / CD / CD-R/RW
  • BD Profile: BD-ROM V2 Profile 2
  • Stereo Up-Sampling to 24/192
  • 7.1ch High Resolution PCM
  • 5.1ch DSD
  • SACD High Resolution
  • Bitstream or Decoding to PCM of Dolby Digital
  • Dolby Digital Plus
  • Dolby TrueHD
  • DTS
  • DTS-HD High Resolution Audio
  • DTS-HD Master Audio
  • 1GB of Internal Memory
  • Twin 1.4 HDMI Outputs
  • Twin USB Connection Ports
  • Ethernet 100BASE-T Connection
  • 802.11 b/g/n Wireless Connectivity Allows Content Streaming
  • Five (5) Wolfson 24/192kHz DACs
  • Up-sampler: Analog Devices ADSP-21261 32 bit running Anagram Q5 upsampling to 24/192kHz (All 10 -channels!)
  • Marvel DE2750 Video Scaler
  • e-Sata External Hard-Drive Connection
  • RS232 Connectivity
  • Video Engine: Mediatek MTK8530
  • Video Scaler: Marvell DE2750
  • Video Frame Rates: 24Hz / 50Hz / 60Hz
  • Ethernet: 100BASE-T
  • Pricing: $1,249.00 MSRP

Sunday, June 5, 2011

Review : M2Tech Young DAC

M2Tech is a relatively "young" company, recently became an established name in the digital audio scene with its industry-standard asynchronous USB to SPDIF converters - The  original hiFace and hiFace EVO. The Young DAC is their first, and currently only stand alone DAC.  M2Tech yet-to-be released flagship will be called the Vaughan DAC and is based on similar core technology and design at around 5x the price.

The DAC is housed in a heavy squarish extruded aluminum chassis with black steel perforated grill in the front. It has two buttons, power switch and source selection. The big LED display shows which source is selected and subsequently the sampling rate. There are a complete range of digital inputs: AES/EBU, RCA, BNC, and Toslink, these are 192kHz capable. And if you know anything about the Young DAC, its 32/384kHz asynchronous USB input is probably what you are looking for.  Power supply is a normal looking 15v wall-wart. Unlike XMOS-based USB implementation, M2Tech proprietary USB connection requires a specialized driver. The latest Windows and Mac drivers are downloadable from M2Tech's website.

The underlying DAC chip used in the Young is a TI Burr Brown PCM1795. To get the DAC to work at 384kHz, the guys at M2Tech bypasses Burr Brown's internal digital filter function and opt for a separate Xilinx Spartan DSP chip to to perform digital filtering and upsampling function. 

The Sound of Spring
We didn't waste time and hooked up our Mac Mini to The Young's USB input.  First impression was that it's a very easy DAC to like.  Its midband is smooth and articulate, and essentially free of flatness and forwardness of lesser DACs.  The treble is well integrated and the bass is more full-bodied than most DACs we have tried recently.  The soundstage was very well-defined with excellent integration between the tonal ranges and the instruments.  Imagery is handled very well where depths are fully painted-in.  

One of its strong point seems to be its adaptability - the ability to get right into the groove with any kind of music we threw at it.  It has the ability to cope with both raucous rock music, and can instantly adapt to lyricism of deep classical passage.  Many competing DACs are good with either soft jazz or classical music, but not rock, less-than-perfectly-recorded-pop, nor electronic music.  Not the case with the Young.  It has an urgent sense of timing to the music, and a great sense of "body" when all the instruments came together.  Central images are clearly individual, yet still part of a coherent whole.  The Young is not the most analytic or detailed, but it is extremely easy to enjoy.  We also tried its S/PDIF inputs and fed it with our reference transport, and the sound signature described above were still very much valid.

Compared to...
We have on hand a similarly priced Calyx 24/192 DAC.  They are similar in size and specs.  While the Calyx is less flexible than the Young (only one RCA SPDIF input), it seems to target the same group of potential buyers - those who wants a reasonably priced but high performance DAC as part of their computer-centric audio system.  We compared the USB input of the two DACs.

The Calyx does not need a special driver for the Mac (it does for Windows, as there are still no native USB Class 2 audio built in to the OS yet).  The Young's driver installation for the Mac/PC is easy enough to install and it works silently in the background without a problem.  We compared both DACs' outputs which matched level using a Mark Levinson 380s preamp.  Even though the Calyx can be powered by the USB port or an external PSU, we use both's included wall warts for comparison.

The Calyx's soundstage was wider and it threw a better "speaker-disappearing" act.  Its micro dynamics and nuances were slightly better.  It seemed to have a blacker background which made instrument separation clearer.  However it did not have the rounded full body midrange that the Young offered.  Bass on the Young was at its full bloom but at the same time not bloated.  Calyx's bass was tight and taut, but integration with the midrange was slightly disconnected, when compared to the Young.  The Young was the more "energetic" DAC of the two, with slightly more upfront presentation while the Calyx is more laid back and "open".  The Young is also more forgiving when not-so-good recordings were played.  The Calyx seems to prefer better recordings where it can excels.

Forever Young
The Young is very a well-thought out device.  We do not know how M2Tech came up with the name "Young", but it is actually very descriptive of the DAC.  Its flexibility  immediacy, adaptability make it a DAC that is easy to listen to, and definitely easy for us to recommend.

Thursday, June 2, 2011

Playback Designs MPD-5

Playback Designs' new MPD-5 uses a proprietary technology called PDFAS (Playback Designs Frequency Arrival System), which claims to completely eliminate jitter.  With an external box, it also connects via USB and can accept up to 24/384khz PCM, as well as 6.1Mhz DSD files.  This is 32 times the resolution of players with the ability to playback 192kHz high resolution files.

Also featuring is a new Apodizing upsampling filter for 44.1 and 48kHz sample rates, which compensate for some of the ringing effects caused by brickwall filters in the Analog to Digital Converters (A/D) used during recording. Depending on the recordings, apodizing filters can provide audible improvements. This is not a new technology and is used mostly to improve reception signals from the edge of dish antennas (satellite). Since brickwalls in A/D converters are akin to edges on dish antennas the same principle holds for digital audio and similar filters can be used in DACs with noticeable improvements.

The high resolution USB connection is through an Extender Box (USB-X) which now is included with the purchase of either of any 5 Series products. This external device gives 5 Series products the ability to playback the super high resolution files of up to 24/384kHz PCM and 6.1MHz DSD.  The USB-X technology is deliberately built into a separate chassis to properly isolate the asynchronous clock from the analog circuitry.

Digital inputs:

  • AES: XLR connector for AES/EBU formatted stereo linear PCM data, up to 24bits and up to 192kHz.
  • S/PDIF: same as AES, but S/PDIF formatted on RCA connector.
  • TOSLINK: same as S/PDIF, but on optical connector.
  • PLAYLINK: Proprietary links to future Playback Designs equipment.
  • PC: Direct USB connection to computers for sample rates up to 48kHz.
  • PC: External USB-X connection to computers for sample rates up to 384kHz (PCM) and 6.1MHz (DSD)

DigiBit Sonata Music Server Software

DigiBit from Madrid introduces SONATA Music Server, a specialized for classical music with audiophile capabilities.

Until now, many true music lovers had resisted switching to digital audio formats and buying downloadable music due to the lack of software and systems able to properly manage the complexity of classical music tags and its unavailability in good quality audio formats. 

Fortunately, more and more music labels are starting to offer downloadable music in the uncompressed FLAC format. The FLAC format provides CD quality or, even better hi-res master studio quality (24bits-96/192KHZ), but the limitation of all media players to handle only 4 or 5 metadata fields (album, artist, genre, track and, in some cases, composer), are insufficient for properly sorting classical music. This inadequate management of metadata has prevented the adoption of digital music by music lovers with thousands of CDs in their collections.

Designed for music lovers with little computer skills, the new SONATA Music Server is a sophisticated software specially designed to handle classical music (and any other genre). The SONATA allows you to select your preferred music the way you want: by genre, period, style, instrument, composer, work, conductor, orchestra, soloists, singers, music label, etc. This will allow users to rediscover in seconds many forgotten records in their music library. For example, you will be able to ask the SONATA to show all the records of Romantic music for Piano by Chopin placed by Claudio Arrau or the Opera records with Pl├ícido Domingo conducted by George Solti or the Jazz records where Charlie Haden plays Latin music. Our proprietary and unique SonataDB and the GD3 database for classical music provide users access to over 40,000 classical CDs, with exhaustive information of each CD saved in 18 fields that, with the help of the also unique “Views” menus, will allow users to perform unique searches by filtering the music library using the most sophisticated combinations as stated above. Covert art is available in hi-res 1000 x1000 and 1400 x1400 format for most classical CDs and above 500 x500 for the rest of the genres.

The top of class CD ripper built-in provides access to metadata from 4 databases (GD3, SonataDB, FreeDB and MusicBrainz) thus, achieving superior metadata retrievals results.  Simple menus, multi-language and multitouch screen support and a very intuitive and easy-to-use GUI makes the learning curve almost inexistent. Selection and searches can’t be easier as the user will always be viewing the covers of the albums/tracks sorted by the criteria he/she had previously chosen.

If users already have part of their collection in digital format, the “Import and Copy” menus will automatically import the music library to the internal hard disk of the server.  SONATA supports up to 4 audio zones, that means users can listen to up to 4 different music programs in 4 different rooms at a time, or the same music in all rooms.

SONATA supports hi-res audio formats and the most advanced features to please the most demanding audiophiles users such as WASAPI and Kernel Streaming and play from memory for a perfect bit plays, thus, becoming a truly audiophile grade music server that supports up to 24bits-192Khz music files.

Besides, thanks to the DLNA/uPnP server, control point and renderer capabilities, user can stream music via LAN or wirelessly to any DLNA renderer such a low-cost or hi-end streaming player, TV, A/V receiver, etc.

Users can install SONATA in a Win 7 Tablet, and then make it a portable media player. As well DigiBit provides several software options to take advantage of the popularity of the iPhone/iPad/iTouch and Android devices so that users can use them to remotely control the music server or to stream music to them. An additional web interface –BitWeb+- allows users to remotely control the music server from any PC in the network.

The optional Sonata DUO software allows users to access their music libraries from wherever they are as long as internet connection is available, an invaluable feature when they’re in the move.

Sonata is available now at for 99 Euros.  Users can download and try the SONATA for free for 30 days.

Wednesday, June 1, 2011

JPLAY puristic audio player for Windows

A brand new audio player for windows, JPLAY was built with only one goal in mind: optimal music reproduction. And that means no music management features, no eye-catching graphical user interface - only a fanatical focus on providing the best possible sound quality.  Its stripped-down, bare-bones playback engine fits entirely inside CPU cache and can be used as stand-alone player or together with popular 3rd party audio players, such as: JRiver Media Center, iTunes, foobar2000, mp3toys etc. 

JPLAY introduces a number of world's-first features for the ultimate Windows music playback. 
  • Full memory-based playback: most other memory-based players dynamically load tracks into memory during playback. In contrast, JPLAY pre-loads complete playlist into RAM guaranteeing no disk activity during playback (zero disk I/O)
  • Large Page Memory: superior memory management provides minimal CPU latencies
  • Maximum System Timer: reduce operating system latency by making Windows switch tasks faster. (0.5ms instead of default 15.6ms)
  • Maximum Priority Scheduling: ensure uninterrupted flow of music data by running music playback at highest possible priority
  • Hibernation Mode: cancel OS ‘noise’ by eliminating dozens of jitter-inducing processes and hundreds of threads
" JPLAY is the first and presently the only audio player, that can totally take control over Windows in a way that nothing else is allowed to run during playback - no processes, threads or services limiting sound quality. In hibernation mode JPLAY uses full power of the PC; all the CPU cores to provide not only bit-perfect stream, but more importantly - 'time-perfect'.
In music, timing is everything. And in digital audio doubly so: while producing bit-perfect output is easy, producing it at exact time required by digital formats (e.g. 32 bits every 22 microseconds for CD) is not. Why? Because while your PC may be really fast, it’s also doing hundreds if not thousands other things at the same time it plays music. With so many things going on, do you trust it will always ‘hit the beat’ at just the right time? Programming optimizations in JPLAY are designed to minimize both software and hardware interruptions in order to make it ‘easier’ for PC to ‘keep the rhythm’.
The player supports both 16-bit and hi-rez audio files in various lossless codecs; FLAC, WAV, AIFF.
JPLAY supports all Windows versions, either 32-bit or 64-bit. Single license costs 99 EUR. More info and free trial version are available at: