The Benchmark DAC2 DX is the DAC2 of choice for users who do not need analog inputs. The DAC2 DX is the only DAC2 model that includes dual stereo output buses.
Made in the USA
Benchmark products are designed and manufactured in the USA.
Benchmark Performance
The DAC2 DX is Benchmark's newest 2-channel D/A converter. When compared to the legendary DAC1, the DAC2 has lower noise, lower distortion, and improved accuracy. The DAC1 became a reference standard in many of the finest recording studios and mastering rooms. The DAC2 defines a new reference.
DAC2 converters deliver outstanding musical detail and precise stereo imaging. They employ 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 includes 3.5 dB of headroom above 0 dBFS. Three balanced 32-bit D/A converters are summed together to form the main output bus. Two channels are reserved for the auxiliary RCA output bus.
The performance of the DAC2 DX exceeds the measurement limits of today's state-of-the art test equipment.
Native DSD Conversion
DSD (in DoP 1.1 format) is automatically detected on USB, coaxial, and XLR digital inputs. The system seamlessly switches between native DSD and native PCM conversion. DoP 1.1 is supported by many media players, and DSD downloads are now available from several sources.
Enjoy seamless transitions between native DSD and native PCM playback.
Direct Connectivity to Power Amplifiers and Powered Monitors
Benchmark DAC1 and DAC2 converters are designed to directly drive power amplifiers and powered 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). The sonic importance of these attenuators cannot be overemphasized. Proper gain matching between the DAC/preamplifier and the power amplifier is essential for achieving peak system performance. The attenuators allow precise matching to all amplifiers and powered monitors.
Passive output attenuators are only found on Benchmark converters - don't settle for anything less.
Sonically Neutral
All Benchmark converters are designed for maximum transparency. This transparency is absolutely essential in the studio monitoring chain. DAC2 converters are ideal for critical reference-quality professional systems. In home applications, the DAC2 delivers the sonic signature that was created in the recording studio.
Hear the music exactly as it was heard in the studio.
Take the Studio Home
When Benchmark's professional converters are used in hi-fi applications, studio-quality sound can be enjoyed in a home environment. Discover the natural, uncolored, analog sound of the DAC2.
Hybrid Gain Control
The DAC2 DX combines active analog gain control, passive low-impedance attenuators, a 32-bit digital gain control, and a servo-driven volume control. All analog outputs are controlled by the rotary volume control unless the volume-control bypass function is selected. This volume control moves in response to commands from the remote control. Audio does not pass through the volume control. The position of the rotary knob is precisely measured, and digital gain coefficients are calculated. The gain coefficients are filtered and passed to a 32-bit high-headroom DSP system. The 32-bit output of this system is connected directly to the array of 32-bit digital to analog converters. This system can provide a wide range of volume control without losing resolution. The DSP system preserves precise L/R balance, and precise stereo imaging, while avoiding any source of noise and distortion.
The volume control is one of the most critical functions in the audio chain, enjoy the best system available.
Low-Impedance Passive Output Attenuators
Benchmark's unique passive output attenuators provide distortion-free gain reduction without reducing the dynamic range (or SNR) of the converter. The attenuators optimize the gain staging between the DAC2 DX 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 and DAC2 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 passive attenuators enable 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
All D/A converters need 3.5 dB "excess" digital headroom, but few have any headroom above 0 dBFS.
All of the digital processing in the DAC2 DX 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 DX 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 delivering significant sonic advantages.
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 main bus feeds the balanced XLR outputs and one set of unbalanced RCA outputs. The main bus uses 3:1 redundancy to reduce conversion noise by 4.77 dB. The redundancy also tends to reduce distortion. A fourth set of conversion channels are reserved for the auxiliary bus that feeds the second set of RCA outputs.
Similar redundancy is built into the native DSD conversion system.
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 analog output stage.
Digital converters are never better than the analog stages that support the conversion process.
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 DX 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 DX. 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 many Linux operating systems without installing drivers. Just plug in the USB, and the DAC2 DX becomes an available audio device.
The USB subsystem remains active when the DAC2 DX 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.
Enjoy the convenience of USB connectivity without any compromise to audio performance.
Digital Diagnostic Display
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 media players apply poor-quality sample rate conversion and truncation. Fortunately these problems can be eliminated with the selection of a good frequency-agile media player. The sample-rate and word-length displays on the DAC2 DX confirm the proper operation of your media player. These tools are also essential in the studio - get instant confirmation of sample rates and word lengths. The DAC2 measures the sample rate and examines bit activity, it does not use metadata flags (which are often incorrect).
Know when High-Resolution Audio is being delivered to your DAC.
Volume-Control Bypass
The DAC2 DX has two analog output busses. Each bus can be placed in a volume-control bypass mode in order to provide a full-level output to a downstream analog volume control. This is useful in many professional applications and is also useful when the DAC2 DX is feeding a Hi-Fi preamplifier.
The bypass function should be enabled whenever a Hi-Fi preamplifier is inserted between the DAC2 DX and the power amplifier. However, for best performance, Benchmark strongly recommends connecting the DAC2 directly to the power amplifier. The DAC2 DX performs all the functions of a DAC and a Hi-Fi preamplifier - a separate downstream Hi-Fi preamplifier can only degrade the performance.
The Volume-Control Bypass provides flexibility for specialized applications.
Digital Pass-Through Function
The second coaxial input 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 be passed through to a surround processor.
The Pass-Through Function provides a coaxial output for any USB-connected computer.
Power Switch
The DAC2 DX will enter a standby mode if the selected digital input is inactive for more than 5 minutes. Operation will resume when the selected digital input become active.The power switch places the DAC2 DX in "full shutdown". Power consumption is less than 0.5 W in "full shutdown". The DAC2 DX will respond the IR remote or the 12V trigger while in "full shutdown".
The DAC2 DX saves energy by meeting or exceeding all standby power standards.
Low Power Consumption
The DAC2 uses high-efficiency low noise power supplies and may be operated from any standard international voltage without adjustment. Low-noise audio circuits require generous amounts of power. High-efficiency circuits in the DAC2 deliver this power without wasted energy.
Power consumption is 12 W - typical.
Distributed Power Regulation
To achieve the lowest possible noise, the DAC2 D uses distributed power supply regulation. Each critical subsystem has at least one dedicated low-noise voltage regulator.
This power system is so effective that there no evidence of any AC line-related hum or noise at the output of the DAC2 - to a measurement limit of -160 dB FS.
"Zero-Ohm" 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.
Driver
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).
Rack-Mount Options
The DAC2 DX is available in rackmount chassis. Non-rackmount versions can also be rackmounted using Benchmark's 1-RU tray. All Benchmark DAC2, DAC1, ADC1, and MPA1 products are housed in a 1/2-wide 1 RU chassis. Two units can be mounted side-by-side in a standard 19" rack. The rackmount version of the DAC2 DX is 1/2 rack wide and requires a blank plate and coupler if mounted by itself.
