The Well-Tempered Computer, an introduction to computer audio

Friday, September 30, 2011

Auralic 24/192 USB DAC

USB audio class 2 compliant DAC
Driver for Win available

According to their website:

Resorting to the ActiveUSB™ technology from AURALiC, ARK MX+ has overcome the transmission limitation from traditional Asynchronous USB which could only adjust +/- one clock cycle error of data package in isochronous clock. With mass data buffer technology and multi-stage, high resolution PLL circuit, ARK MX+ could buffer audio stream as long as 2 seconds, which could prevent time-based jitter resulted from the limitation of computer.

Nice to hear somebody talking about "traditional Asynchronous USB"!

Frequency response: DC - 20KHz, +/- 0.02 dB
Signal/Noise: 118 dB, 20Hz-20KHz, A-weighted
THD+N: <0.0005%, 20Hz-20KHz at 0dBFS
Dynamic range:124dB, 20Hz-20KHz, A-weighted

Output port
Balanced analog output, 4Vrms
Single-ended analog output, 2Vrms
AES/EBU Digital Output*

Input port
USB 2.0 Input** (44.1KHz-192KHz, up to 32Bit)
S/PDIF Digital Input (44.1KHz-192KHz up to 24Bit)

Price: $1499

Wednesday, September 28, 2011

KingRex UD384 & Upower

Kingrex has launched two new products, the UD384 DAC and SPDIF converter, and a matching power supply, the Upower.

UD384 (32bits/384Khz USB DAC )
Input: USB x 1
Analog output: RCA x 2 (Rx1 Lx1)
Digital output :SPDIF x 1        
Sampling rate support :44.1Khz, 48Khz, 88.2Khz, 96Khz, 176.4Khz, 192Khz, & 384Khz(384Khz for USB DAC only)
Supported bit rate: 16 / 24 /32bit
USB:2.0 high speed
Adaptive Clock Generator for Audio Streaming Synchronization
Asynchronous mode changeable through DFU Tool
Power requirement: 7.5V/250mA
Size: 110x82x24mm
Suggested RRP : US$429/pc

U Power
Pure DC output battery power supply unit
      I.       Two output :
A.    2.5mm DC jacket: 7.5V DC output
B.     USB A :5V DC output(through linear regulator)
II.       Major component: High quality Sanyo Li-ion battery.
III.  Power volume: 2600mA/hr. Included special design for isolated protect circuitry for two Li-ion batteries.
IV.  Using fully high quality aluminum for styling & cooling.
V.    Low battery indicator design for charging reminding.
VI.  CHG/DC OUT switch. Fully isolated the charging and discharging. It will free the AC noise from the charger.
VII.   Parallel charging- each battery cell could charge to its maximum by the design.
Suggested RRP : US$179/pc

Tuesday, September 27, 2011

Denon DNP-720AE


dlna 1.5 Certified (AUDIO ONLY)
Windows 7 Certified
Apple AirPlay Certified
USB iPod Direct/Flash/HDD
Made for iPod/Works with iPhone Certified - access to over 12,000 Internet Radio Stations
Pandora Radio Streaming
Rhapsody and Napster Streaming
Price: US$499.99


USB DAC and converter to SPDIF

DAC Crystal CS4398
Sampling Frequency 44.1kHz - 192kHz
Maximum Sampling Frequency 192kHz
Digital input 1 x USB (asynchronous mode)
Digital output 1 x coaxial, 1 x Toslink optical
Output voltage       4V (unbalanced)
Output impedance  100Ω (unbalanced)
Frequency response     20Hz - 20kHz (+/-0.2dB)
Dynamic range 110dB

Unclear whether this DAC is USB audio class 2 compliant.

Monday, September 26, 2011

Abbingdon Music Research

Digital Processor-777 €3.600

24/192kHz Asynchronous USB Audio Class 2.0 (XMOS)
Thermionic Electron Valves
amplification stage:

2 x 6H1n-EV / 1 x 6H11P fitted
ECC88, E88CC, 7308, Cca, 6DJ8, 6922, 6H23n-EV optional
Total Harmonic Dist. + Noise (THD+N): <0.3%
Dynamic range:
>90 dB
Digital Audio Inputs: 2 x XLR/BNC with HD Valve Digital Input technology
2 x RCA/Toslink SPDIF Interface
1 x 24/192 Asynchronous USB

Website: Abbingdon Music Research 

Saturday, September 24, 2011


BitPerfect is a simple high-quality audio player for OSX easy to use, audiophile grade music player that works with iTunes to deliver the highest possible sound quality.
  • Unobtrusive, minimal UI
  • Bit perfect output
  • Exclusive (hog) mode
  • Full memory playback with double-buffering to ensure continuous playback of large files
  • Automatic sample rate switching
  • Options for upsampling
  • Gapless playback
  • Integer mode (on supported DACs and supported versions of OSX)
  • Support for sound check
  • Playback from networked drives
  • FLAC support (via Fluke or other 3rd party iTunes FLAC importers) 
BitPerfect is for sale in the Mac App Store US$ 4.99

Friday, September 23, 2011


Foobar’s Peter Pawlowski has developed a new audio player.
It is a CD player style interface so minimalistic.

Thursday, September 22, 2011

Cocktail Audio X10 Music Server

CD PlayerTypeSlot loading

MP3, FLAC, WAV, WMA, M4A, AAC, Ogg Vorbis, PCM,
Verstärker (eingebaut)Output30W+30W @1KHz, 8Ohm, 1% THD
Headphone100mW+100mW @1KHz, 16Ohm, 0.1% THD
Line out2Vrms @1KHz, 0.1% THD
Display3.5" color-TFT LCD
InputLine(AUX)-in (recording)
outputLine-out,speaker,headphone, SPDIF(Optical out)
ConnectivityNetzwerkWiredEthernet(10/100) LAN
Wireless (Optional)801.11b/g/n WiFi USB Dongle
USBHost X 2eaHigh speed 2.0 Host port
Target X 1eaHigh speed 2.0 Target für PC
Audio formatsMP3, FLAC, WAV, WMA, M4A, AAC, Ogg Virbis, PCM, Playlist(PLS, M3U)
HDType8,9 cm (3.5") SATA(1/2) (*up to 2 Terabytes)
File systemNTFS/FAT32
Languagedeutsch, englisch, französisch, koreanisch, spanisch, russisch, portugiesisch, türkisch, griechisch, tschechisch, hebräisch
PowerAC adapter(24V/3.5A)
Dimensions18(W) X 9.8(H) X 14.7(D) cm

Price: € 299
2 TB + € 100

Loewe Reference media center

Part of the Reference line including electrostatic speakers, subwoofer and a 52-inch LCD TV

  • Playable disks: DVD-Video, DVD+R/RW, DVD-R/RW (Video Mode), Audio CD, CD-R/RW, CD+R/RW
  • Playable formats: CD-DA, FLAC (lossless Audio), WMA, MP3, AAC, WAV, PCM
RAID operation for data security
Database: Gracenotes

  • Antenna FM
  • Audio analogue L/R In/Out
  • Audio analogue Out ( 5.1 channel output)
  • Audio digital In/Out
  • Component Video Out (cinch)/ Composite Video Out
  • HDMI In/Out
  • Headphones
  • LAN
  • RS 232 (RJ12)
  • USB 2.0
  • WLAN
  • iPod/iPhone Dock

Elipson MC-1 Music Server

Technical specifications
  • 2 x 120 W / 4 ohms ICEpower® Amplifier
  • Well® technology: High quality (16 bits/44kHz stereo) uncompressed wireless connection to connect your computer with USB dongle (provided) or iPod®/iPhone®/iPad® dongle (optional).
  • CD Player (MP3/WMA compliant)
  • Sensitive touch panel
  • Optical digital input
  • 2 analog stereo inputs (RCA)
  • USB input (MP3/WMA compliant)
  • MP3 analog input (3.5 mm mini-jack )
  • RDS FM / DAB / DAB+ tuner
  • Headphone output (3.5 mm mini-jack )
  • Pre-amplifier output
  • Subwoofer output
  • Lighting sensor
  • Supply :100-120V / 220-240V AC - 200 W
  • Remote control
A music server without network connectivity.
Wonder what a MP3 analog input (3.5 mm mini-jack ) might be.

Wednesday, September 21, 2011

Cambridge Audio Dacmagic+

According to Sempre Audio a new model including volume control and headphone out is on its way.

KRK Ergo

Firewire DAC with roomcorrection.
RoomPerfect ( Lyngdorf Audio) corrects up to 500 Hz
OSX and Win7 32/64 drivers
ASIO driver

Processing400MHz Analog Devices Blackfin® DSP
RoomPerfect Algorithm Sample Rate96KHz
Room Correction Frequencies20-500Hz
Room correction Filter 1024 tap Finite Impulse Response
S/PDIF Input Operating Range44.1 kHz to 96 kHz
S/PDIF conformityIEC60958-3
Dynamic Range96 dB system (component 118dB)
System THD+N<0.025% using 0 dBFS input and 22-22kHz Band Pass Filter
Internal Sample Rates44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz
Maximum Microphone Input Level-32 dBu
Maximum Line input Level+19 dBu
Maximum Line Output Level+19 dBu
Firewire ImplementationDual 1394a (Firewire400) ports
Dimensions: 180mm (7") x 55mm (2.2") x 107mm (4.2")
Microphone Length: 197mm (7.75")
Weight:610g (21.5 oz)
Power:1394 Bus or External 12v
Operating Temperature Range:40° F (4° C) to 110° F (43° C)
Review in Sound on Sound
Price: US$ 450.00

Meitner Audio MA-1 DAC

  • XMOS USB 2.0 High Speed ​​Interface: 16, 24 bit
    sampling rate up to 192kHz
    Thesycon USB audio class 2 driver for Win
  • Available Digital Inputs:
    • 1x USB
    • 1x AES/EBU (XLR)
    • 2x SPDIF (RCA)
    • 2x TOSLINK (Optical)
  • Word lengths up to 24bit, and sample frequencies up to 192kHz are supported on all digital inputs.
  • Analog Outputs:
    • Balanced (XLR)
    Output Line Level (0dBfs signal on AES/EBU input): 4.6Vrms
    Output Impedance: 300Ω
    • Un-Balanced (RCA)
Price:  US$ 7,000

Aesthetix Pandora DAC

  • Card-based DAC with three digital input slots.
  • AES/EBU, RCA Coax, Toslink standard on digital input 1 slot.
  • USB standard on digital input 2 slot.
  • USB capable of class 1 audio (96KHz, 24bit) and class 2 audio (192KHz, 24bit).
  • 2nd USB input optional.
  • Asynchronous USB, (Streamlength ™)
  • DSP based digital section using Motorola DSP56362 for digital filters.
  • DAC section based on Burr-Brown PCM1792A.
  • Analog section featuring four vacuum tubes in differential configuration.
  • Zero global feedback.
  • Balanced and single-ended outputs.
  • Volume control optional, allows DAC to drive a power amplifier directly. Switched resistor design.
  • Remote control of all functions.
  • Multiple stainless steel faraday cages isolate critical digital, analog and power supply sections.
  • Two transformers, one for digital circuits and one for analog circuits.
  • All aluminum chassis construction.
  • RS232 control.
  • 12v trigger.
  • Unit Weight: 35 Lbs
  • Dimensions: 18" width x 4 3/8" height x 18" depth 
Price:  US$ 5,000.-

XMOS XS1-L1 USB Audio 2.0

A DAC (the chip set doing the Digital to Analog Conversion) doesn’t understand anything about computer audio.
You need a converter to translate the USB input to a protocol (e.g. I2S or SPDIF) the chip does understand.
The XMOS is a popular USB class 2 audio compliant converter used by many manufacturers of asynchronous USB DACs. .
  • USB endpoints use the asynchronous synchronization
  • 500 MIPS, 8 threads, XS1-L1 processor
  • 2 Channel analog input
  • 2 Channel analog output
  • USB 2.0 high speed interface - supports multiple 24 bit, 192kHz channels with extremely low latency (3ms round trip)
  • Plug-and-play with Audio Class 2.0 enabled computers (native Mac OSX support, Thesycon Windows drivers available)
  • Audio Class 1.0 compliant - native Mac OSX and Windows support
  • Asynchronous clocking - complete control of the audio master clock

Basically a USB to I2S converter. Optional support for SPDIF/ADAT/MIDI

Lindemann USB-DAC 24/192


  • Asynchronous USB interface (USB audio class 2 compatible) based on an XMOS-DSP with 500 Mips. Resolution up to 24 bits and 192 kHz. Three separate clocks for USB, 44.1 kHz (and multiples) and 48 kHz (and multiples).
  • USB class 2 driver for Windows
  • Digital interface controller (WM8805WM8805
    with efficient jitter reduction due to buffer storage and adaptive PLL. Guaranteed jitter level < 50 ps.
  • High-precision master clock with < 2.5 ps timing jitter.
  • DAC WM8742WM8742
  • Minimum phase digital filter with apodizing behaviour.
  • Fully-balanced, analog output stage (ADA4927ADA4927
Price: € 690,-

Resonessence Labs Invicta

  • ESS SABRE32 24/192kHz DAC chip
  • Digital filtering DSP and controls via Xilinx MicroBlaze FPGA soft processor cores
  • Ultra-low phase noise oscillator master clock
  • 1 x Toslink input and 1 x Toslink output
  • 2 x BNC digital input
  • 1 x AES/EBU input
  • USB - asynchronous mode, high speed so probably USB audio class 2 compliant but no drivers for Windows available. USB firmware by Cypres Semiconductor.
  • All digital inputs are transformer coupled, galvanically isolated
  • 2 x headphone outputs on front panel, simultaneous drive and levels can be independently set
  • SD card (WAV format only, up to 24/192)
  • Low noise OLED screen
  • Firmware upgradeable (FPGA)
  • High quality AD797 J-FET operational amplifier output stage

The manual contains a lot of measurements.
Each measurement is accompanied by a short explanation, very instructive.
This DAC is linear up to 130 dB. An excellent values allowing for minimal full 22 bits resolution.
Price: US$3.995

Tuesday, September 20, 2011



Wireless USB sender and receiver.
24-bit/96khz digital spdif output (TOSLINK), 192kHz option
Burr-brown SRC4192 sample rate converter
Clock regeneration for jitter-free clocking
Distortion-free volume control (256 step 0dB to -127.5dB digital attenuation)

USB limited to 16/48 but a 24/96 version is planned.

Thanks Seta

Sad to hear you are not able to maintain this blog any longer.

Thanks for supplying us with a plethora of hot news about what is new on the digital audio front.

I will try to keep up the good work.


Digital Audio Blog Announcement

Announcement from Seta, editor Digital Audio Blog.

"Friends, due to personal circumstances Digital Audio Blog's current editors are no longer capable of running this blog to the frequency and quality they intended it to be.  Luckily we do have a savior.  

Digital Audio Blog is now a part of Vincent Kars' reference-standard The Well Tempered Computer website and timely updates of the blog will resume shortly.

Myself and earlier contributors will continue to provide reviews and show reports on these pages from time to time and will be sharing with you some interesting reviews soon."