The Well-Tempered Computer, an introduction to computer audio

Monday, November 26, 2012

Elispson Planet LW

You won’t find many speakers in this blog.
A box, a couple of drivers and a passive crossover have nothing to do with digital.

This one is different.
It is an active speaker so each driver is powered by a dedicated amplifier.
What sets it apart is that there is no analog input.
It uses a wireless connection to get the data from a PC or a iSomthing using a dongle.
Elipson calls it WELL. Wireless Elipson Lossless Link, the internet says it is based on KLEER technology so lossless audio up to 16 bit/44.1 kHz over a 2.4GHz radio link.

2-way active speaker with coaxial driver
2 x 50 W / 4 ohms ICEpower amplifier
Mid-bass driver: 6.5 " (165 mm)
Fabric dome tweeter
Frequency response: 42 Hz - 20 kHz

Website Elispson
Price €1690 (pair)

Sunday, November 18, 2012

Bryston BDA 2

Another DAC with the almost mandatory asynchronous USB input.

 • Dual 192K/32Bit AKM DAC’s
• Independent dual power Supplies
• Discrete Class A analog output stage
• Selectable synchronous upsampling (176.4K/192K)
• Independent analog and digital signal paths
• Inputs: 192/24 USB (1, asynchronous), COAX (2), OPTICAL (2), AES-EBU (1) BNC (2)
• Fully differential balanced XLR and unbalanced RCA stereo outputs
• Transformer coupled SPDIF and AES EBU digital inputs
• SPDIF COAX bypass loop output

Website: Bryston BDA 2
Price: US$ 2395,-

Thursday, November 15, 2012

BNC connectors

You need a true 75 Ohms cable for SPDIF over coax.
Best is to terminate it with true 75 Ohm connectors.
If you don’t you still have an impedance mismatch.
RCA connecters are not 75 Ohm.
That is the reason why BNC connectors are recommended.
Some go as far as to change the RCA receptacle on the DAC by a BNC and buy a cable terminated with BNC.
Be careful because many BNC connectors are 50 instead of 75 Ohm!

Wellshow - BNC Connector Introduction
Digital cables - The Well-tempered Computer

Thursday, November 8, 2012

Ayre Acoustics QA-9 USB A/D converter

AD converters are typically for the pro world.
You need one to record digitally.
The music lover does playback only so needs the reverse of an AD, a DAC.

More and more people start to use a PC as a source for play back.
Why not digitize all of your analog sources?
Ayre Acoustics thinks we will do and launched an AD converter targeted at the home.

A review by JohnAtkinson

Price: $3950

Saturday, November 3, 2012

iFi iDAC

Small pre-amp with line out and headphone out.
24 bit / 192 kHz asynchronous USB input
ESS Hyperstream Chipset

Signal to Noise Ratio: >111dB(A)
Dynamic Range(-60dBFs): >111dB(A)
Crosstalk: <-102db td="td" z="z">
Total Harmonic Distortion(THD): <0 .005=".005" td="td">
Jitter: Below measurement limit
Frequency Response: 3Kz to 33KHz + 0.1dB/0.3dB
Headphone section:
Output Power: >150mW(15Ω)
Signal to Noise Ratio:>97dB(A)
Total Harmonic Distortion: <0 .003=".003" mv="mv" td="td">
Noise:<-86dbu td="td">
Output Impedance:(Zout): <10 td="td">
Power Consumption: < 2.5W
Dimensions: 158(l)x68(w)x28(h)mm
Weight: 193g(0.43lbs)

Website: iFi
Price: US$ 299

Electrocompaniet PI 2D Integrated Amplifier

2 x 100 Watts integrated amplifier with digital and analog inputs.
Digital inputs: two Coax, two TOSLink and one 24/192 async USB
Analog input: 1 balanced XLR input and four single ended RCA inputs.

Technical specifications:
• Input impedance ( Single Ended ): 60 kOhm
• THD + N: < 0.005%
• Output Impedance: < 0,03 Ohm
• Frequency response: 1 – 225kHz
• Channel separation: > 120 dB
• Noise floor ( 1Vrms, 20 - 20 kHz, balanced): <-130 br="br" db="db">• Damping factor: >300
•Rated output power
8 ohms 2 x 100 W
4 ohms 2 x 165 W
2 ohms 2 x 220 W

Website: Electrocompaniet
Price: €3.150