Digital music now comes from a multitude of sources, but your PC's sound card is an afterthought. Pass the same file through the 851D's twin DACs in dual differential mode and its 2nd generation Adaptive Time Filtering process and the music will sound extraordinary - just as the original artist intended.

We built the 851D using all our hi-fi know-how, so it has a large toroidal transformer, audiophile internal components and connectivity with as many sources as possible. There are digital TOSLINK, S/PDIF, BNC and AES/EBU inputs, while if you add a BT100 Bluetooth dongle you can pair with compatible devices. For your PC there's an asynchronous USB audio input with a dedicated driver, allowing you to bypass the PC's poor audio path.

The outpus are similarly designed with flexibility in mind, with both digital, balanced XLR and traditional RCA sockets. As the 851D is also a pre-amp so can be directly connected to a power amp such as our 851W or active speakers for further sonic benefits.

24-bit/384kHz audio upsampling:
The 851D features ATF2 (2nd generation Adaptive Time Filtering) audio upsampling. The ATF2 system intelligently upsamples all incoming audio to 24-bit/384kHz and dramatically reduces digital jitter.

High quality digital pre-amplifier:
Thanks to the highest quality of digital preamplifiers, without bit-reduction, you can connect the 851D directly to a power amplifier such as the Azur 851W to create a truly astonishing digital music system!

Twin Analog Devices DACs:
The 851D features twin Analog Devices 1955 DACs (the Rolls Royce of DACs!) used in 'dual differential' mode for the very best digital to analogue conversion.

Toroidal transformer:
The 851D uses a large toroidal transformer to deliver perfect, low distortion power for all your music.

High performance USB:
The 851D features a high quality asynchronous USB Audio input for playback of up to 24-bit/192kHz high resolution files from a connected computer.

Superior connectivity:
Six digital inputs include S/PDIF coaxial, Toslink optical, as well as BNC coaxial and AES/EBU. Plus there's asynchronous USB Audio and Bluetooth wireless connectivity, meaning that wherever your music comes from, you can play it back in stunning quality through the 851D.

Bluetooth connectivity:
As well as the Standard Bluetooth Codec (SBC), the 851D also supports the higher quality Bluetooth system, aptX, which is supported by more and more devices and sounds even better, meaning you can get the best possible results
from any Bluetooth device.

Selectable digital filters:
The 851D has three selectable filters (linear, minimum and steep) which allow you to choose the sound that best suits your ears.

High quality headphone output:
The 851D's inbuilt high-end, low distortion headphone amp, allows you to get the best possible performance from your headphones; great for when not wanting to disturb others.

Full Metal Jacket:
All the above points would mean nothing if the 851D was not built to last! From the all-metal casework and ultra rigid chassis, to the high-quality, low distortion toroidal transformer, every component in the 851D is designed to give many years of listening pleasure.

DAC: 2 x Analog Devices AD1955
Digital audio inputs:
2 x S/PDIF, 4 x Toslink optical,
1 x BNC, 1 x AES/EBU,
1 x BT100 Bluetooth,
1 x USB Audio
Analogue audio outputs:
1 x Balanced XLR
1 x Unbalanced RCA
1 x headphone output
Dimensions: 115 x 430 x 360mm (4.5 x 16.9 x 17.7'')
Weight: 7.5kg (16.5lbs)