Weiss DAC1-MKIII - D/A Converter 24bit/192kHz with New Analog Section

Weiss DAC1-MKIII - D/A Converter 24bit/192kHz with New Analog Section

The Weiss DAC1-MKIII uses one of the latest DAC chips on the market in conjunction with eight discrete operational amplifiers of our Weiss' own design.  The DAC1-MK3 deliver incredible transparency.

The DAC1-MK3 is a stereo 24 Bit/192 kHz D/A converter designed with the aim of keeping an uncompromising audio signal path. Much detail and thought was spent on the digital input with its extremely low jitter sensitivity, as well as the analog output stages. Options for the DAC1 include interfaces for Firewire and USB, DSD playback and infrared or wired remote control.

Weiss DAC1-MKIII Features

Inputs
There are three digital inputs on XLR connectors, and one on TOSLINK (optical). 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. Each XLR input is actively routed to a corresponding XLR digital output, allowing for monitoring at multiple stages in a digital studio setup.

De-jittering
Several signal re-clocking schemes are combined for extremely high jitter attenuation, making the DAC1 virtually immune to jitter over a very wide bandwidth, down to subsonic frequencies.

Converter
The correlation technique (using two converters per channel) which was already successfully employed in the ADC1, results in improved SNR and THD figures.

Outputs
The DAC1-MK3 uses discrete operational amplifiers of our own design. Called OP1-BP, this operational amplifier probably is the best audio op-amp currently available. Output levels can be set between −infinity and +27 dBu. The outputs are symmetrical, but do not have any sound degrading servo mechanisms built in. For asymmetrical operation only one leg of the XLR connector (plus ground) is used.

Remote control
By hooking up an analog potentiometer or fader to the remote connector, the output level can be remote controlled. This level control happens in the digital domain. The input source selection can also be remote controlled. For the DAC1-MK3 there is a IR remote control option for the output level available.

Front panel controls
The front panel shows four switches for the input selection and various LEDs for sampling frequency, input word-length and signal presence display.

Back panel elements
On the back panel there are three digital inputs on XLR and one optical digital input on TOSLINK. Then there are three digital outputs on XLR, buffered from XLR inputs and two analog outputs on XLR. One of the digital XLR outputs can be switched to output the currently selected input.

The DAC1-MK3 in addition has a rotary output level encoder, which allows to set the output level of both outputs simultaneously in a range of 32 dB with a resolution of 1 dB. The 25 pin DSUB remote connector allows to connect a wired remote control unit for level control and input source selection.

Optional interfaces
Options for the DAC1-MK3 include a Firewire (Thunderbolt) interface and a USB interface. It is also capable to convert DSD to PCM signals which allows to use the DAC1 for playback of DSD signals from a computer. Other options are an ST type glass fiber input and an infrared remote control for the control of the audio volume.

Specifications

Power

• Mains voltage: 115 V or 230 V with voltage selector
• Fuse rating: 500 mA slow blow
• Power consumption: 80 VA max.

Size

• Depth: 30 cm 
• Width: 43,3 cm (19") 
• Height: 4,4 cm (1HU)

AES/EBU Input

• Sampling frequencies: 44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz, 176.4 kHz, 192 kHz
• Maximum sampling frequency deviation: ±80 ppm 
• Maximum input word-length: 24 Bits
• Channel Status Data: Input accepts professional or consumer format
• Connector: Three XLR female (110 Ω), one TOSLINK (optical)

AES/EBU Output

• Three XLR male connectors with buffered versions of the corresponding XLR input. One of the outputs can be switched such that it reflects the currently selected input to the DAC.

Analog Output DAC1-MK3

• Two XLR male connectors, pin 1 ground, pin 2 hot, pin 3 cold
• Symmetrical
• No servo circuit
• Not earth free
• Short circuit proof
• DC coupled
• Class A
• Output impedance: less than 100 Ω
• Output level: variable between −4 dBu and +27 dBu in 1 dB steps

Wired Remote Control Connector

• 15 pin DSUB connector pinout:
• 01 Ground 
• 02 Ground 
• 03 Key #2 (switch to ground, selects input #2) 
• 04 Key #4 (switch to ground, selects input #4) 
• 05 LED #1 (anode of LED for key #1, cathode at ground) 
• 06 LED #3 (anode of LED for key #3, cathode at ground) 
• 07 Ground 
• 08 +5 V supply for external fader (connect fader between +5 V and ground) 
• 09 Not connected
• 10 Key #1 (switch to ground, selects input #1) 
• 11 Key #3 (switch to ground, selects input #3) 
• 12 LED #2 (anode of LED for key #2, cathode at ground) 
• 13 LED #4 (anode of LED for key #4, cathode at ground) 
• 14 Fader channel 1 taper 
• 15 Fader channel 2 taper

Options

• Firewire/Thunderbolt interface
• USB interface with DSD to PCM conversion capability
• ST glass fiber input
• IR remote control for volume control (DAC1-MK3 only)
• Wired remote control for volume control and inout source selection

Measurements DAC1-MK3
Measurements taken at the following conditions (unless otherwise noticed): +27 dBu output level, 0 dBFS input level, 44.1 kHz sampling frequency (fs), 22 kHz measurement bandwidth.

Frequency Response:

• Fs = 44.1 kHz, DC…20 kHz: ±0.25 dB 
• Fs = 48 kHz, DC…20 kHz: ±0.25 dB 
• Fs = 88.2 kHz, DC…30 kHz: ±0.75 dB 
• Fs = 96 kHz, DC…30 kHz: ±0.75 dB 
• Fs = 176.4 kHz, DC…40 kHz: ±0.75 dB 
• Fs = 192 kHz, DC…40 kHz: ±0.75 dB

THD+N at 1kHz:

• At −3 dBFS input: −112 dB
• At 0 dBFS input: −115 dB

SNR at −40 dBFS input:

• 129 dB unweighted, relative to full scale output
• 132 dB A-weighted, relative to full scale output

Linearity:

• From 0 dBFS to −100 dBFS input level: less than ±0.05 dB deviation from ideal
• From −100 dBFS to −120 dBFS input level: less than ±0.2 dB deviation from ideal

Crosstalk:

• Less than −110 dB, DC…20 kHz