Benchmark's DAC1 family of D/A converters have been the reference to which other converters have been compared. It is rare to find a converter review that does not draw comparisons to the DAC1. The DAC1 has been the best-selling 2-channel reference-quality converter and is in daily use at many of the finest recording studios and mastering rooms. DAC1 converters are also enjoyed by thousands of audiophiles. Benchmark has raised the bar ... the DAC2 defines a new reference.
The DAC2 is Benchmark's second-generation 2-channel D/A converter. The DAC2 converter has lower noise and lower distortion than Benchmark's DAC1 converter.The performance of the DAC2 exceeds the measurement limits of some of today's best test equipment.
The DAC2 delivers outstanding musical detail and precise stereo imaging. It employs an advanced high-headroom digital filter design, and a new high-sample-rate Asynchronous USB Audio interface. All inputs are fully isolated from interface jitter by Benchmark's new UltraLock2™ jitter attenuation system.
Internal digital processing and conversion is 32-bits, and this processing includes 3.5 dB of headroom above 0 dBFS. This headroom prevents the DSP overloads that commonly occur in other D/A converters.
Four balanced 32-bit D/A converter are summed together to create each balanced analog output. This 4:1 summation provides a 6 dB noise reduction, and gives the DAC2 industry-leading performance.
Native DSD Conversion
All digital inputs on the DAC2 support native PCM or DSD conversion. From any input, DSD is transported with bit accuracy over DoP 1.1. DSD and PCM are both natively converted to analog. There are no DSD to PCM or PCM to DSD conversions to compromise the quality of the music. The DAC2 conversion system seamlessly switches between native PCM and native DSD conversion. DSD over DoP 1.1 is supported by many media players, and DSD downloads are now available from several sources.
Direct Connectivity to Power Amplifiers
Benchmark DAC1 and DAC2 converters are designed to directly drive power amplifiers and speakers. Benchmark converters feature adjustable low-impedance passive attenuators at the XLR outputs that can be used to optimize the interface to the power amplifier (or powered monitor). This unique Benchmark feature optimizes the gain staging between the DAC and the power amplifier. Proper gain staging cannot be overemphasised. When audio stages are properly matched, each component in the audio chain is able to operate at its optimum signal level, and the system performance is significantly improved.
Sonically-Neutral Studio Monitoring
All Benchmark converters are designed for maximum transparency. This transparency is absolutely essential in the studio monitoring chain. For this reason, DAC2 converters are ideal for critical reference-quality professional systems. Unlike many competing products, the DAC2 is not designed to add "euphonic" coloration to the audio. Instead it is designed to be as uncolored and natural as possible.
Step Into the Studio
When Benchmark's professional converters are used in hi-fi applications, studio-quality sound can be enjoyed in a home environment. Enjoy pure music without any coloration from the electronics. Hear the music exactly the way it was heard in the studio, and exactly the way the artists intended.
Discover the natural, uncolored, analog sound of the DAC2.
Sit in the Performance Space
Transparent sound can go beyond replicating the studio experience. Recordings that have been produced with a natural and unprocessed sound can transport you to the performance space. But, this can only happen when the entire playback chain is selected for maximum transparency.
This experience of "being there" cannot be created by systems that are designed to add "warmth" or "euphonic color" to the music.
"HGC" is Benchmark's unique Hybrid Gain Control system. The DAC2 combines active analog gain control, passive low-impedance attenuators, a 32-bit digital gain control, and a servo-driven volume control. All inputs are controlled by the rotary volume control. This volume control moves in response to commands from the remote control. Analog inputs are never converted to digital, and digital inputs never pass through an analog potentiometer. Digital inputs are precisely controlled in the 32-bit DSP system. The DSP system preserves precise L/R balance, and precise stereo imaging, while avoiding any source of noise and distortion.
Benchmark's unique passive output attenuators provide distortion-free gain reduction without reducing the dynamic range of the converter. The attenuators optimize the gain staging between the DAC2 and the power amplifier. This optimization is absolutely essential for maximizing the dynamic range of the entire playback system. Much of the success of the DAC1 converters can be attributed to the passive output attenuators. Musical details can be obscured by system noise whenever a preamplifier and power amplifier are improperly matched. The" HGC " system will make full use of your power amplifier's dynamic range. Experience new details in your favorite recordings.
UltraLock2™ Jitter Attenuation System
UltraLock2™ is an improved version of the UltraLock™ system used in the DAC1 and ADC1 product families. DSP processing is 32-bits, DSP headroom is 3.5 dB, sample rate is 211 kHz, and jitter-induced distortion and noise is at least 140 dB below the level of the music - well below the threshold of hearing. Benchmark's UltraLock2™ system eliminates all audible jitter artifacts.
High Headroom DSP - with 3.5 dB "Excess" Digital Headroom
All of the digital processing in the DAC2 is designed to handle signals as high as +3.5 dBFS. Most digital systems clip signals that exceed 0 dBFS. The 0 dBFS limitation seems reasonable, as 0 dBFS is the highest sinusoidal signal level that can be represented in a digital system. However, a detailed investigation of the mathematics of PCM digital systems will reveal that inter-sample peaks may reach levels slightly higher than +3 dBFS while individual samples never exceed 0 dBFS. These inter-sample overs are common in commercial releases, and are of no consequence in a PCM system until they reach an interpolation process. But, for a variety of reasons, virtually all audio D/A converters use an interpolation process. The interpolation process is absolutely necessary to achieve 24-bit state-of-the art conversion performance. Unfortunately, inter-sample overs cause clipping in most interpolators. This clipping produces distortion products that are non-harmonic and non-musical . We believe these broadband distortion products often add a harshness or false high-frequency sparkle to digital reproduction. The DAC2 avoids these problems by maintaining at least 3.5 dB of headroom in the entire conversion system. We believe this added headroom is a groundbreaking improvement.
Multi-Mode Asynchronous USB System
Benchmark's USB system supports USB Audio 2.0, DSD, and USB Audio 1.1. It is frequency agile, and will follow sample rate changes initiated by the computer and/or the media playback software. In all modes the USB communications are asynchronous in order to eliminate unnecessary sources of jitter.
The DAC2 has a low-jitter master clock which controls the transfer of audio data from the computer to the USB sub-system. The computer asynchronously transfers audio data to a buffer in the DAC2. The contents of the buffer are then asynchronously transferred to the D/A conversion sub-system. This second asynchronous transfer eliminates any traces of jitter that accumulate as the data is transferred between the USB and conversion subsystems. No traces of jitter-induced distortion are measurable to our measurement limits (better than -150 dBFS). This truly represents the state-of-the art. Enjoy the convenience of computer playback without compromise. The Asynchronous USB system supports USB Audio 2.0 for high-resolution 192kHz, and DSD playback. No drivers are required for MAC operating systems. An easy-to-install driver adds 192 kHz and DSD capabilities to Windows operating systems.
An asynchronous, driverless USB Audio 1.1 mode supports sample rates up to 96 kHz. This USB mode can be selected from the front panel or from the remote control. The driverless USB Audio 1.1 mode allows quick plug-and-play connections to Windows, MAC, iOS, and Linux operating systems without installing drivers. Just plug in the USB, and the DAC2 becomes an available audio device.
The USB subsystem remains active when the DAC2 is powered down. This prevents interruptions to the computer playback operations and eliminates the need to reconfigure the computer every time the converter is turned on.
Quad 32-bit Balanced Conversion System
Four balanced 32-bit D/A converters deliver audio to Benchmark's low-impedance current to voltage converters. The 4:1 redundancy reduces noise and distortion to levels that set new benchmarks. The conversion system at the core of the DAC2 is as good as it gets. The analog circuits that follow the D/A converter are carefully designed. Benchmark has leveraged its long history of building high-end analog audio equipment, in order to create an outstanding output stage.
Diagnostic Tools - Sample-Rate and Word-Length Indicators
Ever wonder why that 192 kHz 24-bit download on your computer just doesn't sound right? Your media player may be down-sampling to 44.1 kHz and/or truncating to 16-bits. Many computers and media players apply poor-quality sample rate conversion and truncation. Fortunately these problems can be eliminated with the selection a good frequency-agile media player. The sample-rate and word-length displays on the DAC2 confirm the proper operation of your media player.
You may encounter recordings with inverted polarity. The DAC2 HGC and DAC2 L include a polarity switch to correct the problem.
Home Theater Bypass
The DAC2 can be integrated into a home theater system. Typically the DAC2 drives the left and right power amplifiers, and an analog feed from the home theater system is connected to either of the analog inputs on the DAC2. A programmable Home Theater Bypass function sets the pass-through gain to unity when the surround system is active. The DAC2 HGC and DAC2 L include an indicator light that is illuminated when bypass is active.
Digital Pass Through
The second coaxial input on the DAC2 can be reconfigured as a digital output. In output mode, any selected digital input (including USB) will pass through to the coaxial output. The digital pass through is bit-transparent and even supports DSD (DoP 1.1). Dolby digital and DTS formats can also be passed through to a surround processor.
Bi-Directional 12 Volt Trigger
Benchmark re-invents the 12 volt trigger. The trigger connection on the DAC2 can be used as an input, an output, or both. It is compatible with any common 12 volt trigger input or output. The trigger can be used to turn a power amplifier on or off automatically. The DAC2 will also respond to a 12 volt trigger to follow the actions of another audio component.
The power switch can place the DAC2 in standby, or full shut down. In full shut down, the unit will still respond to the trigger input and the IR remote control. Power consumption is less than 0.5 W in full shut down.
Low Power Consumption
The DAC2 uses high-efficiency low noise power supplies and may be operated from any standard international voltage without adjustment. Power consumption is 12 W typical.
Distributed Power Regulation
To achieve the lowest possible noise, the DAC2 HGC uses distributed power supply regulation. Each critical subsystem has at least one dedicated low-noise voltage regulator.
HPA2™ Headphone Power Amplifier
The DAC2 features the HPA2™ - Benchmark's signature high-current, 0-Ohm headphone power amplifier. The HPA2™ is arguably the ultimate reference headphone power amplifier. It will deliver the full rated performance of the DAC2 to the headphones. The HPA2™ maintains less than 0.0003% THD+N under full load. The DAC2 has two 1/4" headphone jacks on the front panel. The performance of the HPA2™ remains consistent even when two headphones are being driven simultaneously.
Windows operating systems require a driver when operating in USB 2.0 mode (required for 192 kHz operation). No driver is required for Mac or Linux operating systems. No driver is required for any operating system when operating in USB 1.1 mode (sample rates up to 96 kHz).