ΝΑΙΜ
DAC/Zero S/PDIF Jitter DAC
・Overview
The new Naim DAC is a high performance zero S/PDIF jitter digital to analogue converter.
It is power supply upgradeable, includes eight S/PDIF inputs: Two 75Ω BNC, Two RCA and
Four TOSLINK (EIAJ optical). In addition, the Naim DAC includes a USB (Type A socket)
on the front and rear panels, which facilitate USB memory stick playback and fully
authenticated digital connection from an iPhone or iPod.
・What makes it a Zero S/PDIF Jitter DAC?
Besides the usual attention to the finest detail for which Naim’s R&D is world-renowned and
which will be obvious from the list of key points below, the special element of the design is the
way in the Naim DAC that the master clock is not recovered from the S/PDIF signal as in
other DACs. Instead, the incoming audio data from S/PDIF is stored in solid-state memory
and then clocked back out to the DAC chips using a fixed-frequency local master clock.
This eliminates jitter caused by S/PDIF. In essence the memory, master clock and DAC
structure behaves in a similar manner to the CD, master clock and DAC structure of a CD
player.
The Naim DAC’s high-speed DSP (digital signal processor) front-end is electrically isolated
from its high-resolution DAC and analogue circuits. The two sections are also run from
separate power supplies significantly reducing the effect of RF noise (S/PDIF is a source of
RF noise) from the S/PDIF circuitry on the DAC stage.
Naim’s buffer or memory method of jitter removal relies on a simple concept: the audio data
is clocked into the memory at the incoming inconsistently-timed rate, and is then clocked out
of the memory and into the DAC chips using a precise clock. The rate at which the memory
fills and empties is controlled by selecting the master clock that best matches the average
incoming clock frequency. In this way, the data entering the DAC chips is completely isolated
from the incoming jitter.
The Naim DAC digital filtering is handled by an extremely powerful SHARC DSP chip running
unique Naim authored code to create an ultra high precision 40bit floating point filter. The filter
over-samples by 16 times on 44.1kHz data and provides stop-band attenuation of 156dB with
virtually no pass band ripple. Following the digital filter are the DAC’s two mono Burr-Brown
PCM 1704 digital to analogue converters, as used in the CD555 CD player. Finally, the Naim
DAC features a very high performance, low noise, and low distortion fully discrete analogue
output stage.
・All that technology – what does it sound like?
Naim’s reputation has not been built on technology alone. It has been built on delivering
sound quality driven by solid engineering, clever use of technology and of course consistent
reliability and customer service.
The Naim DAC is no exception; its musical performance is quite exceptional. It combines the
detail, control, and accuracy of truly great digital playback with a musical sense of
performance and inherent rightness that is a joy to listen to. Old and new recordings become
alive, with a sense of renewed vitality and communication.
・Key Points
Zero S/PDIF Jitter design
8 S/PDIF inputs: 2 75Ω BNC, 2 RCA and 4 TOSLINK (EIAJ optical)
2 USB inputs
10 separate sine wave (Colpitts) generated clocks for lowest RF noise generation.
Fixed frequency clocks for zero S/PDIF Jitter
16 Times oversampling of 44.1kHz or 48kHz signals
Automatically switches to asynchronous sample rate conversion if input is out of specification
Memory buffered digital input
Naim custom designed Digital Filtering and 16 times oversampling (aka Integer Upsampling)
Two mono PCM1704 DACs as used in Naim CD555
Power Supply Upgradeable – just add a Naim XPS or 555PS
Includes Apple authentication chip
Full digital connection to iPod (5th Gen onwards) and iPhone
USB Stick music playback to 24Bit 768kHz with control of tracks played
Isolated S/PDIF inputs
Power Supply and Digital processing completely isolated from DACs and Audio Output
Remote controllable: Naim remote or Apple remote
Field upgradable firmware
Ground switchable for optimal performance with all systems
iPod charging is switchable for best sound quality – Not charging sounds better.
SHARC® processor for flexibility in digital filtering and future upgradeability
Fully input integrates with a Naim integrated amplifier or pre-amplifier: becomes inputs 7-10
Front input buttons double as transport function buttons when USB or iPod is connected.
Linear Power Supply
210VA Toroidal transformer with 26 regulated low impedance supplies
New bayonet PCB mounting for all circuit boards
Switchable DIN / RCA analogue output connectors decoupled from case for low microphony
Slim line non-magnetic low-resonance chassis and sleeve
Machined from solid, brushed and anodised front panel
Designed and manufactured in Salisbury England. (£1.950)
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