Introduction High-Definition (HD) digital audio is redefining the quality of recorded audio for the 21st Century. Having created some of the most natural and captivating music sources on the CD standard, AMR has turned its attention to High-Definition audio and in its own imitable way, taken the road less travelled. Our first objective was to deliver the maximum quality of music from the existent libraries of CD standard audio (be it on silver disks or as ripped lossless files) equally balanced with the requirement to also deliver the maximum music quality from the new HD audio formats. We meticulously auditioned the full array of HD DAC chipsets and whittled the field down to one of the latest and most outstanding. Again, the standard textbook implementation was shunned as we applied the same assiduous design and execution of the multi-award winning CD-77 to unleash the full, latent potential of the HD format. Each stage of the signal path is a technical magnum opus focused upon one objective: the most enchanting and pulsating performance. The result is the DP-777 Digital Processor. The DP-777 has the same, unparalleled DNA as every other AMR component; with extraordinary digital advancements never seen before in any converter:
*: World's first, AMR exclusive.
- Gemini Digital Engine (GDE)* Unlike any other converter, at the core of the Gemini Digital Engine, there is not one, but 2 distinct chipsets that define their generation; one latest generation High-Definition 32-Bit DAC to produce the best sound from HD recordings and one Classic Multibit 16-Bit DAC to produce the best sound from CD. These two "non-identical twins" deliver the best of both worlds in a way that is simply unmatched. Further, the Gemini Digital Engine pushes these chipsets beyond what is thought possible. Using Field Programmable Gate Array (FPGA) and Digital Signal Processing (DSP) to handle the core digital duties, including the memory buffer and the signal processing, the outcome are two specially-commissioned DAC chipsets that perform well beyond the textbook.
- Zero Jitter Mode* The Zero Jitter Mode utilises AMR's ingenious Global Master Timing (GMT)* and Intelligent Memory System (IMS) to totally eliminate jitter coming from the source. The Global Master Timing clock system intelligently actualises over 28 million different real-time clock frequencies to exactly match the dynamic input clock down to 0.001Hz (i.e. ~0.04ppm accuracy) of the source. With this new and completely jitterless clock coupled to the Intelligent Memory System (IMS), the GMT/IMS system lock out source jitter once and for all.
- 24/192kHz Asynchronous USB Input The DP-777's 24/192kHz Asynchronous USB Audio Class 2.0 Input is a true asynchronous decoupling of the DAC system clock from the computer that is also fully future-proofed.
- HD Valve Digital input (HD-VDi)* This is AMR's atypical brainchild of using a New Old Stock (NOS) 6N11 high-speed valve designed to operate into several 100Mhz to amplify and purify the high-definition SPDIF signal with zero feedback. Clearly visible on an oscilloscope, with HD-VDi, the signal changes from a blurred to clean and sharp SPDIF signal. Any deficiency in the incoming SPDIF is completely removed.
- OptiValve Output Stage Two NOS valves perform the left and right channel analogue amplification and output buffering duties using the same demanding approach as the CD-77/CD-777; where one half amplifies and the other half buffers without any negative feedback loop. No solid-state devices are present in the signal path.
- High-End Pre-Amplifier The DP-777's direct-coupled/buffered analogue pre-amplifier stage is capable of accepting two analogue sources in addition to the signal internal to the DP-777. The exceptionally precise 71-step resistor matrix-based Analogue Volume Control system delivers unmatched transparency. To attain the highest sound quality, no digital volume control is anywhere to be found.