The Well-Tempered Computer, an introduction to computer audio

Monday, October 29, 2012

AURALiC Vega DAC

DAC supporting both PCM and DSD over USB.
PCM from 44.1KS/s to 384KS/s in 32Bit (352.8KS/s and 384KS/s USB only)

DSD64( 2.8224MHz) and DSD128(5.6448MHz) - 'DoP V1.1' standard, USB only


Frequency Response: 20 - 20KHz, +/- 0.1dB*
Signal/Noise:126dB, 20Hz-20KHz, A-weighted
THD+N:<0 .0003=".0003" 0dbfs="0dbfs" 20hz-20khz="20hz-20khz" at="at" p="p">Dynamic Range:130dB, 20Hz-20KHz, A-weighted

Digital Inputs
1*AES/EBU
2*Coaxial
1*Toslink
1*USB 2.0 buffered by ActiveUSB™

Analog Outputs
1*Balanced(output impedance 2.2ohm)
1*Single-ended(output impedance 50ohm)

Website: AURALiC
Price: US$ 3499 / € 3299



AURALiC Sanctuary Audio Processor

Sanctuary audio processor, the heart of VEGA, is based on multi-core ARM9 architecture with calculating capability at 1000MIPS which is ideal for handling multi-channel high resolution music. AURALiC also introduces the second generation ActiveUSB ™ to VEGA that separates the USB PHY into a discrete chip to future reduce EMI  from computer. Resorting to these technologies, VEGA not only support DXD format(352.8KS/s and 384KS/s PCM signal in 32bit) but also able to decode DSD stream at 2.8224MHz and 5.6448MHz in native though 'DoP V1.1' transmission standard.

Megahertz Upsampling

By using the latest ground breaking algorithm, megahertz upsampling technology can process and up-sample all incoming PCM format to 1.5MHz at 32bit depth. These not only improve the precision of DAC, but also create a new Nyquist frequency for all PCM signal which farther away from the top end of audio frequency. As a result, our engineers are able to design a bran-new analog circuit structure with more bandwidth and faster slew rate. Comparing to previous design, the new structure is more transparent to audio signal with lower distortion and less noise, it also lets red book CDs sound more rich and smooth.

Femto Master Clock

The purpose of Femto master clock is to give DAC an ultimate clock with extremely low jitter and phase noise. It utilizes aerospace grade crystal oscillator, ultra low noise linear power supply and temperature compensation technology to generate master clock with extremely low jitter performance at 82 femtoseconds(0.082 picoseconds). What's more important, the phase noise which affect sound quality a lot has been dramatically reduced to -168dBc/Hz. Driving by such amazing clean clock, VEGA can easily reproduce the music details in the 'last bit', represent a rock solid stereo image you may never experience before.

Fully Customized Digital Filters

VEGA has six built-in digital filters which are developed under AURALiC's subjective auditory sense and objective testing data relationship models. These filters are specially designed to optimize the listening experience for different music and format. The linear phase filter exhibits perfect in-band ripple and out-band attenuation performance while the minimum phase filter is better for enjoyment as it has no 'pre-ringing' effect. There are also slow roll-off filter and several noise filters for native DSD conversion. To maximum usage of these filters, VEGA allows its user to customize according to different formats, tuning sound best to personal preference.

AURALiC ORFEO Class-A Output Module

In order to drive various loads, matching different power amplifiers, VEGsA is equipped with AURALiC's patented ORFEO Class-A module as the output stage which inspired by Neve 8078 analog console’s circuit design. The principle of this module is to use a mass of small signal components with best linear characteristic. By packing them though a thermal balance procedure and bias the transistors into Class-A, ORFEO achieves impressive performance with open loop distortion less than 0.001%. The ORFEO module used in VEGA has been selected and tweaked for lower noise while maintains its driving capability for 600ohm load without distortion raise.


Wednesday, October 24, 2012

Iriver AK100

A portable media player supporting lossless formats like WAV and FLAC up to 24 bits / 192 kHz



MODEL AK100 Specifications:

Display 2.4” QVGA(320X240) IPS Touch Screen
Audio Format WAV, FLAC, WMA, MP3, OGG, APE
Sample rate FLAC, WAV: 8KHz ~ 192KHz(8/16/24bits per sample)
Output Level 1.5VRMS(No Load)
Audio Frequency Response 10Hz to 20KHz +/-0.02dB (24bit 48Khz, No Load)
Signal to Noise Ratio > 110dB (1KHz 0dB, 24bit 48Khz, No Load)
Crosstalk < -120dB (1KHz 0dB, 24bit 48Khz, No Load)
THD+N < 0.0009% (1KHz 0dB, 24bit 48Khz, No Load)
IMD SMPTE < 0.003% (24bit 48Khz, No Load)
Clock Source Clock Jitter 50ps
Storage Flash Memory 32GB [NAND] SD Slot MICRO SD [Max 32GB] slot x 2
DAC Wolfson WM8740 24Bit DAC
Decoding Support up to 24Bit/192kHz Bit to Bit Decoding
Interface USB 2.0, OPTICAL IN/OUT, Headphone Out
Battery Capacity 2,000mAh 3.7V Li-Polymer
Battery Playback Time Max 16hours
Charging time About 5 Hours
Size 59.2[H] X 79 [W] X 14.4 [D]
Weight 122g
Support Firmware upgrade
OS Windows 2000/XP
Website: Iriver
Price: € 799,-

Wednesday, October 17, 2012

Benchmark DAC2 HGC

DAC with volume control, line and headphone out.
DSD over USB ( DoP 1.0)
Supports USB(async) 1 & 2. Driver for Win.
2x4 32-bit DACs
Output: RCA/XLR

Website: Benchmark
Price: US$ 1995