The Well-Tempered Computer, an introduction to computer audio

Tuesday, May 31, 2011

AVM Inspiration C8 CD receiver

Germany's AVM handcrafted Inspiration C8 All-In-One CD receiver is housed in perfectly finished an aluminum cabinet shows no evidence of assembly screws.  Technologically the C8 is very flexible in terms of connections including options for home automation controls i.e. Control4, Crestron etc.  All incoming digital signals are converted to 192kHz/24bit resolution.
  • High Power output stages 150W/channel
  • PureCD drive with slot-in, suspended mounting
  • FM-RDS-tuner
  • 4 Line inputs
  • 1 phono input (MM & MC)
  • 1 processor In/Out
  • 3 digital inputs (SPDIF, optical, USB-Input operates without driver installation)
  • Signal processing in all digital inputs applying 192 kHz / 24 Bit upsampling
  • 2 digital outputs (SPDIF, optical)
  • Tone control and parametric loudness with bypass-mode
  • Remote controllable, solid aluminum easy-to-use remote control included
  • External control via RS 232, IR input via external optional receiver
  • Numerous setup functions (i.e. adjustable input sensitivity, individual input naming etc.)
  • Available finishes: Aluminum silver or black
  • Streaming function as optional module (from mid 2011)

Monday, May 30, 2011

PureAudio Lotus DAC1

A division of Vintage Audio Lab ("VALAB"), PureAudio's Lotus DAC1 uses top of the line AKM 4399 32-bit chip and is can accept up to 24/192 over its SPDIF and I2S inputs while USB is 24/96kHz capable.  Pricing is very competitive at circa US$600.

High grade parts usage:
  • Resistors used on audio circuit are Dale military precision metal film resistors. 
  • Wima mkp and Philips 036 electrolytical capacitors used for chips decouping. 
  • Japanese Rubacon capacitors used for main power filtering. 
  • 1n5062 diodes based rectifiers. 
  • SMD parts and profession circuit layput for high freqnency circuits to get best performance.
  • Matal can Sealed transformer to get lowest EMI interference. 

Digital Inputs:
USB - Support 16bit and 24bit 44.1K/48K/96K sampling rate (Native 24bit 96k supported, not by ASRC sample rate converter)

COAX、OPTICAL、AES/EBU、I2S - support 16bit and 24bit 44.1K/48K/88.2K/96K/176.4K/192K sampling rate

Sunday, May 29, 2011

TAS/Hi-fi+ guide to digital source components

The new version of The Absolute Sound / Hi-Fi+ Guide to Digital Source Components can be downloaded form It is a comprehensive online buyer’s guide that helps audiophiles and music lovers choose among the latest digital source components, from music servers and related hardware accessories and software packages, to DACs, disc players, and integrated amps with built-in USB DACs.

Thursday, May 26, 2011

Orpheus Lab Vanguard Digital Audio Dock

Orpheus Lab's swiss-made "Vanguard" Digital Audio Dock (DAD) has all the inputs you'll ever need.  Allowing connection to any digital audio sources compatible with S/PDIF and ADAT Lightpipe formats.

A large number of connection ports are provided in the DAD including USB 2.0, FireWire 400, Bluetooth AD2P, LAN and USB Flash. The DAD is able to work in multichannel mode with the USB, FireWire and ADAT modules.  It also comes with licensed iPod and iPhone digital transfer compatibility, in a dock which not only enables playback of your iPod/iPhone content but also the recharging of the devices. 

Clocking information is displayed with two LEDs, to indicate whether the Phase Loop Lock (PLL) is locked and whether the system is clocked with an external signal.   The use of headphones has been made as convenient as possible by placing a headphone jack on the front panel accompanied with a volume control. 


  • Word clock IN / OUT (44.1KHz/48KHz/96KHz/192KHz)
  • Firewire multichannel: 8 Channels 24Bits @ 192kHz
  • USB 2.0 multichannel: 8 Channels 24Bits @ 192kHz
  • LAN/Ethernet: UPnP Compliant, Configurable WebRadio 
  • iPod and iPhone Dock.
  • Bluetooth 2.1+ EDR A2DP (iPhone compliant)
  • USB Flash Direct playback 
  • HDMI not HDCP Compliant
  • Optical ADAT: Up to 8 Channels 24Bits @ 48kHz
  • Toslink: 1 Channel 24Bits @ 192kHz
Digital Outputs
  • 4 x SPDIF channels
  • 1 x ADAT
Analog Input
  • 1 x Line In over jack
Analog Output
  • Headphone
  • 1 x Line Out over jack

Digital Audio Player from Plinius and Soulution

Computer Audio is now mainstream.  Most manufacturers now retrofit their CD players with USB inputs. New Zealand's Plinius was showing at Munich High End its Toko Digital Audio Player (est. EUR4,950) a stand-alone CD player with USB input.

Also showing at Munich was the Swiss-made Soulution's Digital Player 540, which uses mechanics from Esoteric, upsamples to 24-bit/384kHz feeding to a pair of Burr Brown PCM1792s.  The player also sports a USB input.

Wednesday, May 25, 2011

Constellation Audio Cygnus and Sirius

Constellation Audio has launched some more accessible pieces (read:prices) at the Munich High End show, including the Cygnus media player pictured below.  Constellation Audio's team is extremely impressive including names like the legendary John Curl and Demain Martin, as well as Andreas Koch of Revox, EMM Labs, and Playback Designs fame.

Cygnus Media Player | Credits:

The Sirius HD Digital Music Source is Constellation's reference digital product and is quite a technological Tour de Force with three separate chassis plus a cool system controller.  

Sirius transport unit
Plays CD, SACD, and DVD-Audio
The Sirius accommodates all of the optical formats commonly used by audiophiles. Unlike many SACD players, it does not downconvert 1-bit digital audio to PCM for playback, so it retains the essential purity of the SACD recording.

Plays digital music files
Digital music files such as MP3, FLAC, and WAV can be played through the Sirius DAC with extraordinary fidelity. These files can be sourced from a USB stick, a computer, or a networked hard drive.

Triple chassis design
Each Sirius comprises three separate chassis. One encloses the digital-to-analog conversion circuitry, another contains the optical disc drive and the digital file player, and the third holds the power supply. The design assures that the electrical and mechanical energy of one component cannot interfere with the circuits of another.

Sirius DAC unit
Triple-transformer power supply
The Sirius power supply module has three separate R-core transformers, each linked to its own voltage regulation circuitry—thus it provides separate power feeds for left channel analog audio, right channel analog audio, and digital/control circuitry. Connections are made through custom-extruded PCOCC wire terminated with aerospace-type Hypertronics connectors.

Sirius power supply unit
C-Link digital interface
In order to avoid down-conversion of the audio from SACD discs, we connect the optical disc/digital file player to the DAC through our proprietary C-link optical interface. This connection also carries PCM signals.

Esoteric VRDS-Neo drive mechanism
The VRDS-Neo is simply the best drive mechanism available. Its Vibration-Free Rigid Disc Clamping System holds a disc firmly so that it can spin at four times normal speed without vibrating—thus producing a low-jitter digital signal that needs less error correction

Line Stage Gain Module
This module serves as a key component of all Constellation Audio products. It is a balanced circuit composed of two mirror-imaged amplifiers, with one amplifying the positive half of the signal and the other amplifying the negative half. Through the use of hand-matched, ultra-low-noise FETs and servo circuits, we maintain an essentially perfect balance between the positive and negative parts of the signal. A machined aluminum shield isolates the module from electromagnetic interference.

Pyxis system controller
Massive solid aluminum chassis
As with our other line-level components, each module of the Sirius is constructed from a single piece of billet aluminum, machined with a wall thickness of 8.2mm to block interference from 50/60 Hz household circuits. The mass of the metal chassis helps damp vibration from external sources.

Tuesday, May 24, 2011

SOtM dx-USB HD asynchronous USB to SPDIF converter

We are starting to see several new stand-alone native USB Audio Class 2.0 USB to SPDIF converters.  These units are most likely based on the relatively new XMOS chip.  Latest is from South Korean's SOtM (that's from "Soul of the Music" get it?).  The dX-USB HD is an asynchronous 24bit/192Khz USB to SPDIF converter.  It will output AES/EBU, coaxial, optical digital and can be powered by the USB bus.  Only thing missing is an I2S output.  Priced at about US$300 and would give M2Tech EVO its run for the money.

  • USB2.0 High Speed, USB Audio Class 2.0 
  • 16/24Bit  44.1/48/88.2/96/176/192kHz
  • Asynchronous mode operation 
  • Drivers for Windows XP-SP3 (32Bit), Vista-SP2 (32Bit), Vista-SP2 (64Bit), 7 (32 & 64Bit), Native with Mac OSX 10.6.4 or above
  • Indicate LED (Power, Sampling rate)
  • Powered by the USB bus, or external power supply 
  • Power regulation circuit  using ultra low noise regulators
  • 400/500MIPS 32bit Multi-threaded Processors (XMOS)
  • Ultra high speed RS422 driver for AES/EBU, Coaxial , Toslink
  • High grade components: PPS film chip capacitor, conductive polymer capacitor, audio grade electrolytic capacitor
  • Dual full size high quality oscillator (one for 44.1kHz family, another for 48kHz)
  • 105x53x150 (WxHxD)
  • Approximately 490g

Monday, May 23, 2011

News from Calyx Audio

Some random updates for the Calyx 24/192 DAC.
  • A beta firmware is in the works for the DAC to support up to 384kHz
  • Calyx is developing a Wireless USB 2.0 device, works with 24-bit 192kHz streaming
  • Calyx Quasar, a LED strobe for testing speed of analog turntables, launching this month
  • Calyx DAC USB works with iPad (1&2, needs USB adapter for iPad) 

Channel D PureMusic 1.8

Channel D's PureMusic is a leading third party digital audio playback software for the Mac, and unlike many, it integrates or "docks" perfectly with iTune using the latter for library management function.  New version 1.8 will have several new features for instance the ability to directly play DSD format audio files at a user-designated PCM sample rate. DSD to PCM conversion is performed in real time during playback. 
A second new extremely innovative feature called "Playthrough" permits conveniently playing other computer audio sources (Internet radio, movies etc.) with full access to Pure Music’s dithered volume control, 64-bit crossover, audio EQ plug-ins, NetSend streaming, metering etc. 

Third, 1.8 will include nonmixable native integer stream format, or "Integer Mode" support, streamlining and bypassing all internal floating point operations on DACs which support nonmixable audio streams. 

Also included are overall usability improvements and correcting all known issues involving gapless playback including those involving Flac files. 

The PureMusic 1.8 update will be free for all users.

Other new features include:
• Menu options to disable all DSP options or disable DSP options except upsampling, mono and invert
• One-click feature to assist in configuring multiway crossover filters
• Option to set the range of the signal level meter (100, 60, 30dB)
• File format or sample rate conversion and adding flac tracks now operate on contents of folders
• gapless break and monophonic tag options in iTunes to denote preferred gapless album track breaks under low memory conditions or to automatically play tagged tracks in mono
• 33% more efficient memory usage with gapless albums
• now observes Repeat One in iTunes for selected track in any playlist
• Improved operation of NetSend connect on launch and disconnect options

M2Tech Vaughan DAC

M2Tech's long awaited ammiraglia, Vaughan DAC (est. US$6,000) was shown on silent display at Munich High End show.  The DAC features 32/384khz capability, asynchronous USB with custom drivers, word clock input, ST glass fiber input, 8 x DAC chip used (4 per channel), dedicated discrete headphone output, and 32-bit digital dithered volume control.
  • Sampling frequencies (kHz): 44.1, 48, 88.2, 96, 176.4, 192, 352.8, 384
  • Resolution: up to 32 bits (USB), up to 24 bits (other inputs)
  • Inputs: USB (B-type female), S/PDIF (2 x RCA and 2 x 75 Ohms BNC, dual AES for 384kHz), AES/EBU (2 x XLR dual AES for 384kHz), Toslink (2 x for dual AES), ST (2 x for dual AES), straight I2S, external master clock 
  • Outputs: single-ended on RCA and balanced XLR, plus a headphone ouput on 6.35mm jack socket
  • Power supply: 115-230VAC, optional battery PSU.
  • Controls and display: standby and select buttons, encoder, dual large matrix display to show locked frequency and selected input.
  • The Vaughan features 8 D/A IC's (4 per channel in mono mode). A digital dithered volume control will allow for using the Vaughan as a preamplifier. The headphone output is made with a discrete components amplifier.
  • Brushed aluminum case and grilled front panel
  • Dimensions: 440 x 80 x 440 mm.

An outboard Lithium-polymer battery power supply unit with low-noise regulators will power the Young DAC.  Housed in a matching case and to be called the "Young Supply" (right box in the picture below).  Whether it will also power the Vaughan is still unclear.  The left box is a prototype A/D converter called the "Joplin".

Pictures courtesy of Cybwiz.

Sunday, May 22, 2011

Qat Audio MS5 Music Server

Beijing's QAT Audio launched the new MS5 music server system (US$5,900) at Munich High End show.  It has integrated hard drive for storage plus a CD-ROM drive for ripping files directly to it. 

Available in different colors with proprietary OS on the included screen remote control unit for selection and playback. Quality components all around.

● TEAC CD drive
● Built-in 1TB capacity 3.5-inch Seagate Enterprise hard drive for music data storage;
(Storing up to 2000 music CDs by using FLAC lossless format); connection with other storage tools via USB interface)
● Proprietary operating system, fully remote-controllable
● Supported audio formats: PCM, WAV, APE, FLAC, AIFF, WMA, M4A, MP3, AAC, Ogg Vorbis and future formats via software upgrade
● Supports internet radio
● Supports 192 KHz/32 Bit master formats and playback music
● Asynchronous Sample Rate Converter: Analog-Devices AD1896 chip converts 44.1KHz/16Bit digital music up to 192 KHz/24Bit, thus improving performance
● DAC: Balanced DAC circuitry, 2 x Analog Devices AD1955 192KHz/24Bit chip (supports SACD’s DSD decoding)
● Full Balanced output with proprietary full discrete OpAmps consisting of FET and Bipolar devices. Very high slew rate with high drive capability
● Aluminum, fan-less chassis design
● Analog outputs: RCA, XLR
● Digital outputs: RCA, USB
● Digital inputs: USB
● Network connection: RJ45
● WDH: 425×370×265(mm)
● Weight: 12.7Kg

Bel Canto DAC 3.5VB review by Positive Feedback

Bel Canto DAC 3.5VB as reviewed by Robert Lerner at Positive Feedback Online.

" I'm an audiophile because of the music I grew up on in Chicago blues bars. Those bands, those venues were not about ambience and delicacy. The music was direct drive of the soul. I wanted that feeling in my house… that uplift. And while my taste in music and the reproduction of it has broadened and gained in sophistication—I still value an upfront, direct communicator above all. I'd sacrifice the subtle, beguiling midrange glow of the Ayre, and the slightly deeper, more 3D presentation of the Berkeley for the direct feed quality of the Bel Canto. "

Friday, May 20, 2011

Interesting launches at Munich High End show

CH Precision C1 D/A Controller
Matching DAC (with DSD support) and controller for its earlier D1 CD/SACD player.  CH Precision was founded by ex Orpheus Lab guys and is based in Switzerland.

Pro-Ject Stream Box Reference
The SE version will have a very nice features range including 24-bit/192kHz playback, high resolution screen, high speed USB, at real world price of 700€, typical of Austrian Pro-Ject.  As reported by

Weiss INT203 firewire to AES/EBU interface
Successor to the INT202.

Credits: Taiwanese high-end audio website

Bladelius USB DAC

Swedish Bladelius Design Group's first in a series of mini accessory products is a USB-only DAC.  The Asynchronous USB DAC is 24/192kHz capable (based on the XMOS chip) and is powered by the USB port but signals are galvanically isolated.  It uses a minimum phase type filter with no pre-ringing to achieve a more natural sound with less digital harshness.
  • 24 bit/192 kHz
  • Asynchronous USB transfer, re-clocking with a fixed low jitter crystal clock
  • Galvanic isolation between USB and the analog circuits
  • Super low noise power supply with multistage regulation and filtering
  • Low order modulator for low out of band noise 
  • Digital filter with minimum phase
  • Analog output stage is a high performance / high drive (output 2.5v)

Thursday, May 19, 2011

Devialet HD Asynchronous Wifi Streamer

Devialet will be annoucing at the High End Show in Munich its HD Asynchronous Wifi streamer board for the D-Premier.  It will be free of charge to existing owners and will be included in the new units to be shipped.  
The D-Premier comes standard with a WiFi antenna and the new module will allow streaming of up to 24/192kHz files from iTunes via WiFi right into the unit with clock controlled from the D-premier to avoid potential jitter.  A PC/Mac driver is needed to provide correct buffers between iTunes and Wifi transfer protocol.

Also to be announced is the Devialet LaSuite™, an all-new high end audio+video integrated system from the Company.

Recent reviews from Soundtage and 6moons here.

Wednesday, May 18, 2011

Chevron Audio Paradox 8i DAC

England's Chevron Audio Developments has an interesting proposition for its Paradox 8i DAC.  Rather than using the usual over/upsampling techniques, or just going plain Non-oversampling ("NOS").  They interpolate incoming data using 8 dac chips driven with the same original data but at precise time differences. When the output of the DAC chips are summed together the result is an increase of data bit depth from 16 to 19 and increase of sample rate from for example 44.1KHz to 176.8 KHz. This is achieved without digital filtering which is considered by many to produce unsatisfying sound quality.
"Key to the design is the elimination of digital filtering used in most CD systems, as part of the over sampling or up sampling process. The effect of digital filtering is to blur the sound such that it sounds somewhat bland and lacking in dynamics. This is the main reason that reproduction of music via LP records has retained a large following. 
The reason for digital filtering is to remove the alias signals that occur at ultrasonic frequencies as a direct result of the analogue to digital recording process. For example with (redbook) CD the conversion is done 44,000 times per second (44KHz) which allows information to be recorded up to 22KHz but when reproduced there is also a mirror image of the recorded information from 22KHz to 44KHz. This sounds like a bad thing but actually human hearing does not extend beyond 22KHz and it is able to effectively filter out the unwanted information. There is also the risk that the 22KHz-44KHz signals will adversely affect reproduction equipment indirectly leading to sound degradation but in practice this is extremely rare."
To reduce jitter they have developed their own reclocking circuitry "ChronoClock" with ultra low noise power supply. This process reduces jitter nearly as low as can be achieved with crystal oscillators but allows different sample rate data to be received. The DAC can receive any data rate up to 100KHz.

The dac chips output current signals are passively converted to a voltage signals. The voltage signal is however buffered by an active circuit to provide a low output impedance signal capable of driving any interconnect cables.

USB interface is also developed in house. Starting with a low noise power supplies to power the USB interface via the DAC rather than via the computer. Ground isolation is also used to prevent possible ground loop noise. The signal is passed through its jitter reduction circuit (mentioned earlier) to clean up the signals before feeding to the dac chips.

Multiple torroidal transformers power the Paradox DAC, there are 5 isolated power supplies to minimise undesirable interaction between circuits. All voltage regulators are fast high bandwidth types combined with low impedance capacitors to give low noise at audio & Radio frequencies.
  • Inputs - USB type B, SPDIF coax 75R and Toslink optical. Balanced input is optional.
  • Outputs - RCA unbalanced stereo.
  • Contols - Phase can be inverted 180 deg. Some recording give a better sound-stage with phase inverted.
  • The Paradox DAC is available in 4 versions, its possible to upgrade to the better versions at a later date:
  1. Standard Paradox DAC uses a high performance opamp output stage. Price - £520.
  2. Paradox 8i DAC adds 8 times interpolation. Price - £610.
  3. Paradox 8i Plus DAC uses a non opamp output stage powered by Hypex regulators. Price - £750.
  4. Paradox 8i DAC Deluxe same as Plus DAC but with an external power supply. This arrangement isolates any electrical noise radiated by the transformers or rectifiers from the DAC circuits. Also included in this power supply are additional active ripple reduction circuits which allow the voltage regulators in the DAC to work more effectively. Price £970.

Tuesday, May 17, 2011

Ukiro's Daniel Weiss Interview's posted an interview with Daniel Weiss which was taken in February at the Stockholm high-end fair.  It's interesting to see how his 10 man company turned focus from pro-audio to high end consumer products, and how he values technical objectivity than subjective listening.


Alex Peychev's APL Hifi is finalizing his state-of-the-art digital to analog converter.  The new DAC-M has obviously very impressive specs.  Enhancing on the DAC-S, which we previously covered. It comes with AES/EBU input, asynchronous USB and two Coaxial S/PDIF inputs.  Sporting unprecedented 20 AKM AK4399s 32-bit DACs per channel. It has a transformer-coupled tube output stage featuring special custom Oxygen Free Copper Lundahl audio transformers, and pair of the vintage new old stock E182CC tubes. The unique remote controlled H-Attenuator with 0.5dB step is also intact negating the need of a preamplifier. All-aluminum IR remote is included.

The DAC-M is an all-hand-made with point-to-point wiring. The Italian made aluminum enclosure is 17x12x3.5 inches.  Special, custom, oversized P-Core transformer is specifically hand-made for the DAC-M.  Introductory price is $19,500 including 5 years warranty and shipping.

Burson Audio DAC-160

Australian Burson Audio's claim to fame was its excellent HA-160D headphone amp+preamp+DAC which uses Burson's proprietary discrete operational amplifiers (not IC OpAmps, also available as upgrade modules for other products).  Burson is back with a stand alone digital to analog converter dubbed the DAC-160 which is based roughly on the DAC section of the HA-160D, housed in a handsome machined aluminum case.

  • 2 x 24/96 USB inputs 
  • 10ppm low-jitter clock
  • 1 x each 24/192 Coaxial and Toslink SPDIF inputs
  • 2 x fixed analog RCA outputs with high/low gain switch. 
  • All voltage regulators and OpAmps are built up from discrete components
  • Output stage operates in Class A with constant current source power supply
  • Two low noise power transformers 
  • Input impedance is 52 Kohms
  • S/N ratio is >101dB at 0dB gain
  • THD is <0.001% at 6mW/300 ohms
  • Channel separation is >95dB/10kHz 
  • Output impedance is 25/45 ohms selectable
  • Power dissipation is <25W
  • Dimensions are 180 x 250 x 80mm, 5kg 

Wednesday, May 11, 2011

Magico Q1

US-based Magico is a relatively new comer in high end speaker scene but gained its reputation quite rapidly with several well known reviewers (especially TAS's) calling the Q5 "quite possibly the best loudspeaker in the world".  They are expanding the all-aluminum Q-range with a smaller Q3, and the stand mount Q1.

The Magico Q1 (US$24,950) is a 2-way stand-mounted monitor housed in a fully-braced, fully-damped, aluminum and copper, hard-anodized enclosure. The Q1 features a complete new set of agicodesigned drivers including a new 7” Nano-Tec® woofer that has been developed to deliver improved system efficiency and greater power handling. This allows the Q1 to be satisfactorily powered by high quality amplifiers with as few as 50 Watts

The Q1 is to replace the speaker that put Magico in the spotlight.  The iconic US$32,000 Mini II which stands as a classic, its influence rising far above the resulting industry disquiet. For Magico, it marks the starting point of an even greater pursuit. 

The Q1 is representative of this pursuit in both the demands it meets from a performance stand point and the technology it employs to achieve that. Tireless driver development has yielded two new drive units allowing for better power handling and an additional 7Hz of bass extension than the venerable Mini II. Continued research into the damping mechanism used in the Q platform has also resulted in addressing the common problem of resonance in the stand mount. Instead of attempting to add mass to the stand and decoupling the speaker, the Q1 is directly coupled and the stand itself is a damping mechanism.

As in most products, addressing problems with more precision allows us to carefully consider a broader range of demands. In the Q1, compromises of form factor, bass, power requirements, and versatility were not necessary due to eliminating inefficiencies in common problem solving design principles. The outcome is a compact, convertible stand-mounted/bookshelf loudspeaker with explosive, true full-range performance. It is the 2-way monitor that has never before been built, by our company or any other.

Driver Complement:

1 x 1” MBe 1 Tweeter
1 x 7” Nano-Tec Bass

Sensitivity: 86dB
Impedance: 5 Ohms
Frequency Response: 32 Hz – 50 KHz
Minimum Power: 50 Watts
Dimensions Including Stand: 44” H x 15.2” D x 10” W (112cm x 37cm x
Weight:120 lbs. (54 kg)

We will getting a loaner unit of its bigger brother Q3 soon, although not a subject of this blog, but we want to have the best equipment to review all the digital gears.  Stay tuned!

Sunday, May 8, 2011

6moons reviews the Resonessence Invicta

Some excerpts:

[As compared to the Weiss DAC2/Minerva]
"After many hours of mounting comparative frustration, the upshot was that those who've always wanted a Minerva/DAC2 with USB instead of Firewire input plus a far bigger feature set including headphone drive, remote control, finely calibrated volume and SD card slot now have one. Sonics weren't just from the same school. They were from the same class and virtual doppelgängers. The one aspect I could consistently tell apart (recording permitting!) was that the Weiss with its more centralized soundstage focus lightens in density or substance towards the sides where the Invicta maintained more consistency. Its stage spread was equally solid on the sides as it was in the center. There also were very small textural/timbral differences. Those I could make out at the very beginning of each track whilst focusing down hard on individual instrumental tones. Describing it however proved elusive. What's more, this very minor change of scenery lighting receded from my attention fix so quickly that even though it was a consistent occurrence from track start to track start, it just as consistently was too subtle and slippery to remain identifiable for more than a few seconds. With properly matched levels I doubt anyone could tell these machines reliably apart. Those who hoped that 'best in the world' claims for the ESS Sabre chip meant a real rung or two higher up on that ladder in the sky would eye the Burr Brown BB1792 in the Weiss with real consternation."

[As compared to the Burson Audio HA160D]
"This distinction translated not so much as additional top-down illumination or aeration as it had with the Zodiac Gold + Voltikus vs. Burson. There textures for the Antelope machine had come across as somewhat fluffier, airier and lighter. Whilst the Burson's retrieval or recreation of recorded space was once again less keen to make it sound meatier or more robust, this wasn't 'per se'. Clearly top to bottom the Invicta did not trail it on image density. This difference seemed to simply be a psychoacoustic function. Equal material substance acquires different weighting when one is considered more on its own—just the steak, no sizzle—and the other in the context of surrounding space (with sizzle).

I must confess that whatever expectations of an unconditional next plateau or higher octave I might have had based on the firm's unusually comprehensive technical documentation were somewhat disappointed. As I was with the top Antelope machine I'm convinced that the Resonessence is digitally the more advanced. I also remain convinced that team Burson's insistence on going full-on discrete in the analog domain is responsible for their fleshier sound..."

Thursday, May 5, 2011

Peachtree Audio DAC●iT

Peachtree Audio the maker of popular iNova and iDecco digital-ready integrated amplifiers announced a new model - DAC●iT which slots-in under the company's current iDac at a lower price point of US$449. The unit is based on the ESS Sabre ES9022 chip with three digital inputs: USB (24/96 adaptive), Coax SPDIF (24/192), and Toslink optical (24/96).  The digital inputs are transformer-coupled for ground isolation, USB input also features galvanic isolation. Dimensions are 2.42" H x 6.5" W x 6.5" D, which is the same foot print as previous generation Mac Mini.  

Been to any live performance lately?

Well we did, but not a classical nor acoustic jazz performance.  Deadmau5 was DJ-ing electronic/techno music. 100% digital - not even vinyl - 100% computer-based performance.  The sound was fantastic, extraordinarily full range.  The production was awesome.  Once in a while, you need live performances to know what your system should sound like.

Tuesday, May 3, 2011

Devialet D-Premier vs Weiss DAC202 has posted an interesting comparison between the Devialet digital integrated amplifier and the Weiss Dac 202 + Pass Int-150 set up.

Monday, May 2, 2011

Review : Kingrex PSU Mk2

They say garbage in, garbage out.  Think about it, the sound you are hearing from your audio system, is actually energy from power plant, sub station, power transformer, home junction box, power outlet, and then your equipment.  Taking cues from recordings and convert electricity to sound waves.  

It's been said that sonic contribution of a typical DAC would be 30% DAC chip, 30% analog output stage, 30% power supply, and 10% for the other parts combined.  Your typical consumer piece of equipment often comes with cheap wall-warts or switching power supply which in itself is notorious for noise - which is measurable and often heard.  Psycho-acoustically we perceive this as "grunge" and "edginess" rather than higher noise floor. 

Soon after our review of the Calyx DAC 24/192, kind readers were suggesting that the DAC may be better treated with an outboard power supply.  During our original review, the Calyx was powered primarily by USB.  It uses an energy storage and regeneration circuit, internally generates 12v voltage rail and outputs 6.5v over its balanced XLR outputs from USB's mere 5v.  The included wall wart was tested and found indifferent in terms of sound quality.  We were equally curious whether we can still improve it excellent sound quality so we contacted Kingrex for a review of their latest Power Supply Unit, which is in its Mark II incarnation.

Kingrex PSU MK2 power supply unit is available in 3 models with output voltage 12V, 9V, 5V.  The units are priced at just below US$350 each.

The 5V version would power the Calyx DAC 24/192, Squeezebox Touch, Onkyo ND-S1 iPod Transport, etc.  The 9V version would power a Wadia 170i/171i Transport, Squeezebox Classic/Duet, M2Tech EVO.  12V version also available.

Inside the PSU Mk2 there's a 48VA toroidal transformer, a regulated power-stabilizing circuit with 8 capacitors, 5 x 2200μF at AC input stage and 3 x 4700uF at DC output stage. 6N Furukawa PCOCC wiring through out.  The unit has a 3 pin Neutrik DC connection on the PSU side to DC jack (electronic side). The included DC jack is a 5mm external, 2mm internal type, which is actually too short for Calyx's input.  We had to modify it by cutting the original jack out and replace with a longer one.  If you plan to use the PSU with the Calyx, please request a longer DC jack from Kingrex.

The Calyx has a selector in the back that switches between USB power and 5v DC, so it is easy to compare the effect of two power sources with out having to match levels or  interconnects etc.   There was a soft "click" when changing the power source and that's about it.  During this test we used Wireworld Platinum Starlight USB cable whose unique feature is the isolation of power leads from data conductors. 

Results? First was Bill Evan Trio's Waltz for Debby in 24/192kHz format.  To get the cymbals in this recording right is one of the test we constantly use to fish out digititis so common in lesser equipment.  Cymbals should bite, but at the same time never harsh.  There should be air with nice natural decay. Both USB power and PSU performed equally well.  We also couldn't hear much difference on the piano nor the softish acoustic bass.  We were quite impressed how clean the Calyx's USB power regulation is.  Next up were Herbie Hancock's Imagine Project and Manu Katche's Third Round - both excellent modern-day jazz recordings with serious bass and drums.  Now the Kingrex/Calyx combo proved to be something the Calyx alone always wanted to be!

Deep bass now has fundamental we never thought missing.  Subjectively, we felt that the low end extension extended down another octave or so.  It is also ironic when you have more infrasonic reach, you feel you have more "air" as well, even though the upper frequency range is more or less the same.  With air, you have a better sense of where the images are in the sound field.  Room ambiance are now better portrayed.  The soundstage becomes more three dimensional.  Slam and weight were also noticeably better with more visceral impact without muddying the mid-bass.  Calyx was a little short on pace and rhythm last we tested it, but now with the Kingrex PSU Mk2, the DAC can now really boogie.  The combo closes the gap with our reference Weiss DAC 202...much closer than before.

We also have on hand a Squeezebox Touch, which we upgraded with a Teddy Pardo Power Supply and found it to be a notch better than stock wall wart.  We did tried the Kingrex on the Touch and thought it offered the same level of performance as Teddy's (tighter bass and extended highs than stock).  Just a caveat that the magnitude of improvements are not as significant as the Calyx's but worth the upgrade if you opt for best possible sound from the Touch.

Highly recommended.