The Well-Tempered Computer, an introduction to computer audio

Wednesday, November 30, 2011

WAV vs FLAC


One of the many endless debates in computer audio is WAV vs FLAC.
Some people report an audible difference. Most of the time in favor of WAV.
Other says this is plain make belief, placebo, etc because when FLAC is converted back to WAV the result is bit identical.
Others argue that the processing power to convert FLAC to raw PCM is higher than in case of WAV so this might affect the timing (jitter).

An obvious downside of WAV is the lack of a tagging standard resulting in poor portability of the tags between media players / playback devices.
FLAC has a well-supported tagging schema.

From R14.1 on dbPoweramp has an option: uncompressed FLAC.
Now you have your uncompressed WAV with the tagging capabilities of FLAC.
Looks like the best of both worlds.

A bit more:

Saturday, November 26, 2011

Klangwerk Ella


System 2 way active
1 tweeter
3 midrange/woofers
Price € 13.200 (pair)
Frequency Response 36 - 22000 Hz (-6dB)
Cabinet Bass Reflex
Dimensions 1130 x 216 x 190 mm
Digital input
-
Analogue input XLR
Amp Class G  120 + 40 W rms
Crossover 1600 Hz

Website Klangwerk

Friday, November 25, 2011

Cambridge Audio DacMagic Plus



  • Twin Wolfson WM8740 24bit DACs used in dual differential configuration
  • New Anagram Technologies ATF2™ 24-bit/384kHz audio up-sampling / jitter reduction
  • Optional Digital Preamp mode allowing connection directly to power amp or active speakers
  • 24-bit/96kHz driverless USB Audio 1.0
  • 24-bit/192kHz USB Audio 2.0 with ASIO or kernel streaming modes.
  • USB class 2 driver for Win
  • Asynchronous USB transfer 
  • Selectable digital filters - linear phase, minimum phase and steep
  • Balanced XLR audio output and RCA phono output
  • Two 24 bit digital inputs (with optical or coaxial for each)
  • External input for optional BT100 Bluetooth receiver - allows audio to be streamed and up-sampled from any paired Bluetooth device

Price: £349.95

Wednesday, November 23, 2011

Manger MSM C1

Type Active 2-Way System
Price from € 13200,- per pair incl. 19% VAT
Cabinet Enclosure closed
Dimensions (H x W x D) 44.8" x 10.6" x 8.4" (1139 x 270 x 214 mm)
Weight 105.7 lbs (48 kg)
Frequency Range 30 Hz – 40 kHz
Drivers Tweeter: Manger Sound Transducer, Bandwidth 80 Hz – 40 kHz, Rise Time 13μs
Woofer: 8"(200 mm) fibreglass-Polyester sandwich cone, 38 mm voice-coil
Crossover 330 Hz
Amplifiers LF: 250 W @ 8 Ohms
HF: 180 W @ 8 Ohms
Power Bandwidth HF: 250 kHz (-3 dB)
Input XLR-3 (balanced)
Finish Silk matt as per RAL, Nextel or piano finish

Website: Manger

Friday, November 18, 2011

Centrance DACmini PX



DAC 24 bit
Headphone out: 1.5W (headphone output, total), drives 32...600 Ohm headphones
Speaker out: 50W (speaker output, total), drives 4...8 Ohm speakers 
Line out

Inputs
USB: 24 /96 adaptive mode 
S/PDIF: Up to 192 kHz Coax
Toslink

Price: $1475.00
Website: Centrance


Wednesday, November 16, 2011

Highres recordings

CD quality is 16 bit / 44.1 kHz sample rate.
Today you can buy 24 bit / 192 kHz recordings.
 Can your gear resolve this?


Let’s do some calculations (always tricky in my case)

Playing 192 kHz is 1/192.000 sample per second= 0.000005208333333333330 s
If the clock driving the DAC has an intrinsic jitter of 10 nano seconds then time step produced at DA conversion fluctuates between:
0.00000001 = 10 ns
0.000005218333333333330 +10 ns
0.000005208333333333330
0.000005198333333333330 -10 ns

Obvious the fluctuations in clock speed are pretty close to the time step.
Ok, let’s use a better clock, one with an intrinsic jitter of 1 pico second.

0.000000000001 = 1 ps
0.000005208334333333330 +1 ps
0.000005208333333333330
0.000005208332333333330 -1ps

In this case the variations in the time step look more decent.
The higher the sample rate the more import low jitter values become.
Of course jitter performance is far more complex but it looks like even a clock with an extreme low intrinsic jitter of 1 ps is not able to generate the correct time step.
So our gear can’t play 192 kHz with the right timing!

A bit more: http://www.whatsbestforum.com/showthread.php?4402-Timing-is-everything

Friday, November 11, 2011

Rein audio X-DAC


1. Digital input:
USB 2.0 Interface:16Bit, 24Bit sampling depth; 32kHz, 44.1kHz, 48kHz, 96kHz sampling
Coaxial RCA / Fiber Optic:16Bit, 24Bit sampling depth; 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz, 192kHz sampling
Clock jitter (44.1kHz): S/PDIF less than 100PS; USB less than 100PS

2. Line output
XLR balanced and RCA unbalanced
Dynamic range: greater than 114dB
SNR (A weighted): greather than 114dB
Total harmonic distortion: less than 0.0006%
Frequency Response (20Hz~20KHz): +-0.5dB
Max Level: RCA Line 2V rms; XLR Line 6V rms
Output Impedance: 100O

3. Other
AC power input Specifications: 220V, 50/60Hz
Power consumption: <20W
Color: Black
Case Material: iron case, aluminum wire drawing process panel
Dimensions (cabinet): 220x190x65 (mm)
Weight: about 2.2kg

4. Interface
Faber Optic x 1 input
Coaxial RCA x 2 input
USB (Type B) x 1 input
RAC unbalanced x 1 output
XLR balanced x 1 output

5. Features
XLR Balanced output
Support S.PDIF input format: PCM
Support the highest digital input format: 24Bit/192KHz
Manual input selection
USB 1.1 PC interface, Drive support: Windows XP / Server 2003 / VISTA / 7, Support ASIO 2.0

Website Rein Audio

Monday, November 7, 2011

HIGHRESAUDIO


Highresolution music download-service HIGHRESAUDIO expands its offering with Universal Music.

Among the repertoire are new releases and for the very first time Classical Masterpieces from Bach, Bruch,
Debussy, Haydn, Mahler, Liszt, Vivaldi and others in studio-master quality with a sampling-rate of 96kHz, 24-bit from Decca Classics and Deutsche Gramophon.
More Genres such as Jazz, Pop and Rock are to follow in the next coming months from Universal Music.

Other labels available: 2L, Abeille Musique, ACOUSENCE, Acoustic Music
Records, AEOLUS Records, Animato, Bee Pop/Jazz, B-Ton, Carpe
Diem Records, DACAPO, Chaos, Chandos, Delos Music, ECM,
Fondamenta, Intergroove, Jazzland, KML Recordings, Laborie,
Melisse, NAIM Label, Naxos, Neuklang, New Amsterdam Records,
Ozella Music, PentaTone, Songlines, Sony Music, Stockfisch,
Termidor, Universal Music, Winter & Winter, Yarlung Records,


The average album price at HIGHRESAUDIO costs around 20 € (£17) and tracks 2 € (£1,70).

Website: www.highresaudio.com