Page 2
Congratulations on your purchase of the DAC202 D/A Converter and welcome to the family of Weiss equipment owners! The DAC202 is the result of an intensive research and development process. Research was conducted both in analog and digital circuit design, as well as in signal processing algorithm specification.
OWNERS MANUAL FOR WEISS DAC202 D/A CONVERTER TABLE OF CONTENTS A short history of Weiss Engineering Our mission and product philosophy Advanced digital and analog audio concepts explained Jitter Suppression, Clocking Upsampling, Oversampling and Sampling Rate Conversion in General Reconstruction Filters...
OWNERS MANUAL FOR WEISS DAC202 D/A CONVERTER A SHORT HISTORY OF WEISS ENGINEERING After studying electrical engineering, Daniel Weiss joined the Willi Studer (Studer - Revox) company in Switzerland. His work included the design of a sampling frequency converter and of digital signal processing electronics for digital audio recorders.
2007 Introduction of the CASTOR, our High-End Hi-Fi Power Amplifier 2008 Introduction of the MINERVA Firewire DAC and the VESTA Firewire – AES/EBU Interface 2010 Introduction of the DAC202 Firewire DAC, the INT202 Firewire Interface and the ATT202 Passive Attenuator Page...
OWNERS MANUAL FOR WEISS DAC202 D/A CONVERTER ADVANCED DIGITAL AND ANALOG AUDIO CONCEPTS EXPLAINED Jitter Suppression and Clocking What is jitter and how does it affect audio quality? In the audio field the term jitter designates a timing uncertainty of digital clock signals. E.g. in an Analog to Digital Converter (A/D) the analog signal is sampled (measured) at regular time intervals;...
(jitter). Think of the PLL as beeing like a very slow-reacting flywheel. In the DAC202 we employ a two stage PLL circuitry which very effectively suppresses jitter. A common problem with most PLLs used in audio circuitry is that they suppress jitter only for higher frequencies.
Page 8
OWNERS MANUAL FOR WEISS DAC202 D/A CONVERTER (DSP)) ahead of the final D/A conversion (the D/A chip), while oversampling means the change in sampling rate employed in today’s modern D/A converter chips themselves. But let’s start at the beginning. What is the sampling...
OWNERS MANUAL FOR WEISS DAC202 D/A CONVERTER frequencies between 0 and 20kHz go through unaffected and frequencies above 22.05kHz are suppressed to maybe 1/100'000th of their initial value. You are right, such a filter is very steep and as such has some nasty side effects.
Analog Output Stages The DAC202 employs separate output stages for the main output and the headphone output. Both stages use state of the art operational amplifiers with high slew rate. A topology with a very low output impedance has been chosen.
Page 11
OWNERS MANUAL FOR WEISS DAC202 D/A CONVERTER after the upsampler the word length may be higher than the subsequent processor may be able to accept. In this example, after the upsampler there may be a D/A converter with a 24 bit input word length capability. So if...
OWNERS MANUAL FOR WEISS DAC202 D/A CONVERTER THE DAC202 D/A CONVERTER Features in alphabetical order Absolute polarity switch: The absolute polarity of the outputs can be inverted for optimizing the sonic impression. Audio Inputs: One XLR, one RCA and one Toslink connector for AES/EBU or S/PDIF signals.
Page 13
OWNERS MANUAL FOR WEISS DAC202 D/A CONVERTER Dual / Single Wire modes: The AES/EBU inputs / outputs of the DAC202 normally work in the so called “Single Wire” modus, i.e. both audio channels are transferred via a single cable. The DAC202 also supports the “Dual Wire”...
Page 14
96, 176.4, 192 kHz. For all input modes the synchronization source can be freely chosen. E.g. with Firewire as input the “Internal” synchronization is typically chosen, which means that the DAC202 is the master clock for the computer. Page Date: 03/10...
DAC202. Playing back these files via the player software to be checked allows the DAC202 software to recognize the bit pattern of the files. If the bits of the files are changed during playback e.g. because of a volume control or EQ or upsampling algorithm etc., the bit transparency check...
Page 16
LED is turned off and after a short while the LCD screen comes on. Note that if a computer is connected to the DAC202 via Firewire, the sync source and sync frequency (if applicable) have to be selected from within the Weiss Firewire IO window on the computer.
Page 17
OWNERS MANUAL FOR WEISS DAC202 D/A CONVERTER Pressing the knob again enters the “Options Menu”. Rotating the knob instead of pressing it navigates to the input source select as shown here. Pressing the knob again allows to select the input source. If any parameter...
Page 18
- WC BNC: This selects the BNC connector at the rear of the DAC202 as the synchronization source. If the DAC202 is used in dual wire mode read the instructions for the dual wire mode regarding external synchronization.
Page 19
This mode is selected if the DAC202 is used as a preamplifier. If bypassed, the volume knob and the remote control volume work only on the headphone output.
Page 20
To do this you need to play the audio files supplied on the CD coming with the DAC202. Copy these files onto your drive holding your audio files. There are two files for each sampling rate, one at a 16 Bit wordlength (I.e.
Page 21
This paragraph describes some advanced features of the DAC202: The Insert mode, the Dual Wire mode and external synchronization via Wordclock on the BNC connector or via the other digital audio inputs.
Page 22
OWNERS MANUAL FOR WEISS DAC202 D/A CONVERTER XLR selected as sync source: XLR signal goes to Firewire. RCA selected as sync source: RCA signal goes to Firewire. Toslink selected as sync source: Toslink signal goes to Firewire. Internal or WC BNC or 1394 bus selected as sync source: The Firewire output is muted.
Page 23
OWNERS MANUAL FOR WEISS DAC202 D/A CONVERTER - The DAC chip is fed from: XLR input (left channel) and RCA input (right channel). Mode: AES(XLR) input / single wire / no insert - The XLR input is routed to: DAC chip, XLR out, RCA out, Firewire out, APB.
Page 24
OWNERS MANUAL FOR WEISS DAC202 D/A CONVERTER Mode: S/PDIF(RCA) input / single wire / insert active - The RCA input is routed to: XLR out, APB. - The DAC chip, Firewire output and RCA output are fed from the XLR input or Toslink input as selected in the insert menu.
Page 25
OWNERS MANUAL FOR WEISS DAC202 D/A CONVERTER Mode: S/PDIF(TOS) / dual wire / no insert - The XLR input (left channel) and the TOS input (right channel) are routed to: DAC chip, XLR out (left channel) RCA out (right channel), Firewire out, APB.
7. Confirm "Continue Installation" when warned that the computer requires a reboot after install. 8. Click Restart After installing the drivers, connect the DAC202 to the computer and connect the power cord to the DAC202. Switch the DAC202 on. The DAC202 should now be recognized automatically.
(XLR, RCA, TOS) the sampling rate indicated reflects the one fed from the external device. Sync Source: The clock to which the DAC202 should sync to. Usually this is the DAC202’s internal clock generator. Buffer Size: Larger buffer sizes increase robustness against dropouts, lower buffer sizes provide low latency.
Page 28
Try other modes if there are clicks in the music. Note that when using the XLR, RCA or TOS in-puts there is no need to hook up a computer to the DAC202. Global Settings / Info: Information about the driver version.
OWNERS MANUAL FOR WEISS DAC202 D/A CONVERTER Technical Data Digital Inputs: (1) XLR connector, (1) RCA connector, (1) Toslink connector (optical), (2) Firewire connectors. All inputs accept professional or consumer standard , i.e. accept AES/EBU or S/PDIF signals. Sampling Frequencies: 44.1, 48.0, 88.2, 96.0, 176.4 or 192kHz on any of the inputs.
Page 30
OWNERS MANUAL FOR WEISS DAC202 D/A CONVERTER Synchronization: Synchronized via input signal, internal oscillator or via a wordclock signal (TTL level / 75 Ohm) on BNC input. Sampling Frequencies: 44.1 kHz, 48.0 kHz, 88.2kHz, 96.0kHz, 176.4khz, 192kHz. Wordclock output (TTL level / 75 Ohm) on BNC for synchronization of other equipment.
Need help?
Do you have a question about the DAC202 and is the answer not in the manual?
Questions and answers