Benchmark

The DAC1 USB is a reference-quality, two-channel 192kHz, 24-bit audio digital-to-analog converter, featuring Benchmark's UltraLock technology. The converter is designed for maximum transparency and is well suited for critical playback in studio control rooms and in mastering rooms. The compact and rugged enclosure makes the unit an excellent choice for location recording, broadcast facilities and mobile trucks. An internal power supply supports all international voltages and has generous margins for over and under voltage conditions.

The unit features the exact same topography as the original DAC1, but with several additional features. These include a USB input with bit-transparent native 24-bit/96kHz capability, and a programmable mute function. The headphone output now has a programmable headphone gain range. Also added is an automatic standby/resume feature, along with a high-current output stage designed to drive long cables or low-impedance loads, such as high-end power-amplifiers.

Multiple Usage

Essential equipment for mastering studios, high quality recording studios, high-end home audio systems, or anywhere un-colored digital playback is demanded.

Digital Inputs

Four digital inputs (balanced XLR, coaxial, optical and USB) are provided and are selected from the front panel. The XLR, coaxial and optical inputs accept either professional or consumer formats. The USB port has a maximum of 96kHz sampling rate.

The USB input is compatible with Windows 2000, XP and Vista, as well as Mac OS X, and does not require driver installation or system configuration.

True plug-and-play solution, designed to begin playback immediately after the unit is connected to a USB port for the first time.

HPA2 Headphone Amplifier

Two 1/4" headphone jacks are driven with Benchmark's HPA2 high current headphone amplifier. The amplifier is capable of driving a wide variety of headphone loads while achieving less than 0.0003% distortion under load. The gain control sets the output level of the headphone jacks.

Direct Connectivity with Monitors

Interfaces directly with power amplifiers and powered studio monitors in order to provide the cleanest and shortest path from digital to monitor output. Ten, 20 and 30dB pads are provided for interfacing to studio monitors having high input sensitivity.

The gain control can be used to control the output level of the balanced XLR and unbalanced RCA analog outputs.

The left-hand headphone jack includes a switch that mutes the XLR and RCA analogoutputs when a headphone plug is inserted. This mute feature can be disabled with internal jumpers.

Features high-current output drivers that are capable of driving 300Ω loads without an increase in distortion. They are also well suited for driving long cables or high-capacitance loads.

Jitter Immune

The UltraLock system is 100% jitter immune. The D/A conversion clock is totally isolated from the AES/EBU digital audio clocks in a topology that outperforms two-stage PLL designs. No jitter-induced artifacts can be detected using an Audio Precision System 2 Cascade test set.

Any AES/EBU signal that can be decoded by the AES/EBU receiver will be reproduced without the addition of any measurable jitter artifacts. In addition, the receiver IC has been selected for its ability to decode AES/EBU signals in the presence of very high levels of jitter.

Soft Mute

Designed to perform gracefully in the presence of errors and interruptions at the digital audio inputs. A soft mute circuit eliminates pops when a digital signal is applied. Power management circuitry controls the muting and resetting of all digital circuits upon removal and application of power.

Audio is present at the outputs only 60ms after applying a digital input signal and only 500ms after applying power to the unit.

Avoids all unnecessary mute scenarios. Muting is only enabled upon loss of power, or when digital transmission errors occur. The DAC1 does not mute when the input data is all zeros. Consequently, no audio is lost when an audio transient follows full silence.

Sample Rate

Operates even when sample rate status bits are set incorrectly. Sample rate is determined by measuring the incoming signal. Lack of sample rate status bits or incorrectly set status bits will not cause loss of audio.

Phase accurate between channels, and between other DAC1 boxes. A fully digital de-emphasis circuit supports 44.1, 48, 88.2 and 96kHz sample rates and is automatically enabled in response to the pre-emphasis status bits of consumer format digital signals.