Mapleshade USB-TO-S/PDIF Reclocking Adapter
The Reclocking Adpater’s input is a USB data stream from any PC or Mac USB port. Any standard frequency and resolution up to 192kHz/24bits is accommodated. The Adapter outputs a very high quality S/PDIF stereo audio output signal via standard RCA coax digital interconnects to your system’s DAC (or CDP with digital input). This diminutive Reclocking Adapter incorporates astonishing circuit sophistication and several key elements essential for high quality, high resolution playback:
• Low jitter, low phase noise, high stability clock oscillators. Most audio interfaces and USB DACs use phase lock loops to derive their clock from the incoming noisy USB data stream, which introduces heavy jitter (i.e. the data timing errors that make even the finest DACs sound harsh). Instead, our Reclocking Adapter utilizes two extremely precise quartz, highly stable crystal clock oscillators; temperature stability is 2-5ppm approximately, compared to 50-100ppm for the clocks normally used on commercial CD players. These crystal clock oscillators independently and asynchronously reclock the output data stream to eliminate from the S/PDIF output data the sound-degrading jitter inherent in the USB input. That large jitter reduction greatly reduces listening fatigue and digititis; imaging, ambience, harmonic detail, analog warmth, transient dynamics and bass articulation all improve notably.
• Carefully-filtered, regulated power supplies for the clocks, buffers, formatting logic and output transmitters. To keep the noise on the input USB 5 V bus from introducing new jitter, the Adapter’s extremely compact circuit board incorporates three independent supply regulators and filter networks.
• Low dielectric absorption, non-conductive, vibration-reducing enclosure. Even highly miniaturized circuits like these suffer from signal-induced internal vibrations. Our Amish woodworkers assemble a beautifully crafted (and ultra-low dielectric absorption) maple enclosure directly to the circuit board, thereby greatly stiffening the board while creating an ample sink for draining internal board vibrations. This maple enclosure avoids the sound-muddying effects of high dielectric absorption of the usual plastic enclosures-or, alternatively, the energy-robbing eddy currents that plague any metal enclosures (eddy currents are inevitably induced in any conductive wire or plate near signal circuitry). A final step after assembly is cryogenic treatment; this significantly reduces background grunge, thereby enhancing ambience retrieval, treble sparkle and the sustain of notes or chords fading into silence.
• Proprietary drivers. Standard audio processing in the Microsoft and Apple operating systems greatly constrain the potential for outputting good sounding audio from computers. Designer Marco Manunta has created proprietary drivers for his brilliant reformatting/reclocking circuit that allow the music player software to transfer audio data without loss of resolution, by-passing 96kHz frequency constraints imposed by Microsoft/Apple operating systems and bypassing their internal sound-degrading kernel-streaming processing.
• Compact size, ease of use and elimination of the USB cable. The extremely compact design of the complex processing circuitry of the Adapter makes it possible to plug directly into the USB 2.0 port of any computer. This eliminates the otherwise-essential USB cable interconnect, a major sonic advantage because even the best available high end USB cables induce significant jitter and clearly audible sonic degradations (S/PDIF interconnects carrying the music data stream from the Adapter to the DAC, notably our Clearviews, can be made far more jitter-free and clean sounding than any USB cable). An additional convenience is that no external power supply is required; the Adapter draws current from the USB bus then regulates and filters the power internally.
||Happy owner of the Mapleshade USB to S/PDIF adapter
|I have been using the Mapleshade adapter since October 2011, connected to my old Denon AVR. My computer is an old single core Athlon powered Windows XP machine.
I play lossless FLAC using Foobar2000, the tracks are either 24bit 96Khz or 16bit 44.1Khz. Since this adapter is not supported for ASIO, I have been using ASIO4ALL which as I understand it is a WDM wrapper which gives ASIO like performance for non-ASIO devices.
I have been very happy with the adapter, but it was only when I recently upgraded my AVR to a high-end Pioneer model that I had anything to compare it against. Since the Pioneer includes its own USB-DAC, finally I had something to compare it against. Comparing the Mapleshade adapter to the USB-DAC really makes the Mapleshade adapter stand out. I will refer to the USB-DAC simply as the Pioneer.
I find the Mapleshade adapter is more musical compared to the Pioneer. I find the Pioneer struggles when the music gets busy, with the many instruments merging together, becoming a blur. By comparison I find the Mapleshade adapter to have no problem when there is a lot going on. It manages to keep the sound stage controlled and tight. The other difference I have noticed is that the Mapleshade adapter is very good with vocals, especially female vocals such as those of K D Lang. The Pioneer sounds quite good in this respect, but not nearly as good as the Mapleshade.
Another noticeable difference is that the Mapleshade adapter is able to clearly reproduce subtle sounds such as the intake of breath which as singer is sometimes heard to make on some recordings. With these sounds, the Pioneer it is not nearly as clear and precise. With the Mapleshade adapter, I find this characteristic makes the whole listening experience more authentic.
I hope that this review is helpful to anyone considering purchasing the Mapleshade adapter. In my experience it has been worth every penny.|