Weiss DAC2 - Firewire D/A Converter 24bit/192kHz

Weiss DAC2 - Firewire D/A Converter 24bit/192kHz

The Weiss DAC2 is based on the renowned DICE Firewire chip of the TC Applied Technologies company on the digital side and on the equally well received Burr Brown D/A converter chips on the analog side. The combination leads to a flexible and very good sounding D/A Converter.

As a high performance stereo, Firewire based, digital to analog and digital to digital converter, the DAC2 can be used either standalone or in conjunction with a PC or MAC computer. It allows for various format conversions like Firewire to analog, AES/EBU to analog, Firewire to AES/EBU, AES/EBU to Firewire. In addition it offers a digital insert point between the Firewire input and the analog output. The analog output level can be controlled via the front panel keys.

Weiss DAC2 Features

Inputs
There are three digital inputs on XLR, RCA and TOSLINK (optical) connectors. In addition a computer can be connected via a Firewire interface. The accepted sampling frequencies are 44.1, 48, 88.2, 96, 176.4 and 192 kHz. AES/EBU signals in single wire or dual wire formats can be used. Digital outputs on XLR and RCA connectors are used to convert Firewire to AES/EBU and also for the insert point feature described below.

De-jittering
The DICE Firewire interface chip in the DAC2 uses a dual PLL scheme for clock (re-)generation. This yields a very high jitter suppression down to subsonic frequencies.

Output, level control
The DAC2 uses THAT line driver chips with low output impedance and excellent distortion figures. Separate driver chips are employed for the XLR and the RCA outputs. The output level can be set in the analog domain in four coarse steps to accommodate for the subsequent amplifier. Fine tuning of the level can be done via the digital level control which is operated via the front panel keys

Front panel controls
The front panel shows a power key, three keys for the input selection and four LEDs for sampling frequency display. The front panel keys have several functions: The selecting of the input source, the enabling or disabling of the “insert mode”, which allows to insert a digital device in the signal chain between Firewire input and analog output and finally the setting of the output level in the digital domain with “up/down” controls.

Back panel elements
On the back panel there are three digital inputs (XLR, RCA, TOSLINK) and two Firewire sockets. Then there are two digital outputs (XLR, RCA) two pairs of analog outputs on XLR and RCA. The screwdriver operated rotary switch allows to set the analog output level in four coarse steps

Internal jumper settings
Internal to the DAC2 there is a jumper to select the dual wire mode for 176.4 or 192 kHz signals.


Bit transparency check
The DAC2 allows to check the player software running on the computer for Bit transparency. This is done by playing a test audio file on the computer. The DAC2 then checks whether it receives the special Bit pattern from the test file. This check is running in the background of the DAC2 software, i.e. as soon as the DAC2 detects such Bit patterns it flashes three of the LEDs on the front panel.

Optional interfaces
Options for the DAC2 include an USB/DSD interface which allows to play back DSD files via the DAC2. A ST type glass fiber input is another option. For connecting the DAC2 to Thunderbolt there is a Thunderbolt to Firewire adapter available from Apple® at low cost.

Specifications

Power

• Mains voltage: 115 V or 230 V with voltage selector
• Fuse rating: 250 mA at 115 V, 500 mA at 230 V, slow blow
• Power consumption: 7 VA max.
• Power consumption in stand-by mode: 3 VA max.

Size

• Depth: 30 cm
• Width: 18,8 cm
• Height: 6,6 cm (1.5HU)

AES/EBU Input

• Sampling frequencies: 44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz, 176.4 kHz, 192 kHz
• Maximum input word-length: 24 Bits
• Channel Status Data: Input accepts professional or consumer format
• Connector: One XLR female (110 Ω), one RCA (75 Ω), one TOSLINK (optical)

AES/EBU Output

• One XLR male connector
• One RCA connector

Firewire Input/Output

• Two Firewire 400 sockets to allow for daisy-chaining of Firewire units
• Balanced Analog Output
• Two XLR male connectors, pin 1 ground, pin 2 hot, pin 3 cold
• Symmetrical
• Servo circuit, i.e. pin 3 can be grounded for asymmetrical outputs
• Not earth free
• Short circuit proof
• DC coupled
• Output impedance: 50 Ω

Output level selectable via a rotary switch at the back:

• +17 dBu (5.48 Vrms) with a 0 dBFS sine wave input
• +11 dBu (2.74 Vrms) with a 0 dBFS sine wave input
• +7.2 dBu (1.78 Vrms) with a 0 dBFS sine wave input
• +4.8 dBu (1.35 Vrms) with a 0 dBFS sine wave input

Single Ended Analog Output

• Two RCA connectors
• Asymmetrical
• Short circuit proof
• DC coupled
• Output impedance: 50 Ω

Output level selectable via a rotary switch at the back:

• +17 dBu (5.48 Vrms) with a 0 dBFS sine wave input
• +11 dBu (2.74 Vrms) with a 0 dBFS sine wave input
• +7.2 dBu (1.78 Vrms) with a 0 dBFS sine wave input
• +4.8 dBu (1.35 Vrms) with a 0 dBFS sine wave input

Options

• Thunderbolt interface via the Apple® Thunderbolt adapter
• USB interface with DSD to PCM conversion capability
• ST glass fiber input
• Software
• Firewire drivers for Windows™ and OSX™ operating systems are supplied

Measurements
Measurements taken at the following conditions (unless otherwise noticed): +17 dBu output level, 0 dBFS input level, 48 kHz sampling frequency (fs), 22 kHz measurement bandwidth.

Frequency Response:

• DC…20 kHz: ±0.3 dB

THD+N at 1 kHz:

• At −3 dBFS input: −97 dB

SNR at −20 dBFS input:

• 107dB unweighted, relative to full scale output

Linearity:

• From 0 dBFS to −120 dBFS input level: less than ±1 dB deviation from ideal

Crosstalk:

• Less than −110 dB, DC…20 kHz

Inter-channel phase response:

• Less than ±0.5°, DC…20 kHz