The Onkyo ND-S1 is broadly speaking an Ipod Dock, but a
more correct title for the ND-S1 is a ‘digital media transport’. The reason for
this is that the ND-S1 takes an unfettered digital signal from the Ipod before passing
it on via coaxial or digital, whereas most other docks take an analogue signal.
The internals of the ND-S1 shares some similarities with
the Wadia 170, both use the Texas Instruments PCM2704/5/6/7 chips, a Stereo
Audio DAC with USB Interface. The ND-S1 is a lower cost product, and cost
cutting is clearly seen between these two docks. The quality of PCB’s, extent
of power supply decoupling, bypassing; are all a lesser affair in the ND-S1,
but then it is £250.00 cheaper!
One advantage with the cost saving is these funds can be
used to invest in to key areas of the ND-S1 to boost performance. We have
developed two levels of upgrades, level-1 improves the unregulated power supply
by adding a Bulk decoupling capacitor to the DC input, the stock unit has only
a 0.1uf capacitor so we install an OS-CON SP capacitor to reduce noise and add
stability to the 5V supply rail. The generic 3.3V digital regulator is replaced
with a Super-regulator 3, this significantly improves Power Supply Rejection
Ratio (PSRR), the power supplies ability to reject noise at the input. The
Super-regulator provides and extremely low noise, low impedance 3.3V supply
delivering clean power to the circuits. The general purpose decoupling
capacitors are replaced with Sanyo OSCON SVP. At the digital output we add a
Bybee Slipstream purifier to clean up the digital signal. To finish we add
Sontech SFRT-AL resonance control to the chassis.
Level-2 installs all the upgrades as per level-1 but with
the addition of a Bybee Slipstream purifier on the DC input. The RCA phono for
digital out is upgraded to a WBT NextGen cu type.
Onkyo
ND-S1 Level-1 Upgrade
Sanyo OS-CON SP for DC input.
Super-regulator 3 for 3.3V digital supply.
4x Sanyo OS-CON SVP for local decoupling.
Bybee Slipstream purifier for digital out.
Sontech SFRT-AL resonance control.
Onkyo ND-S1 Level-2 Upgrade
Bybee Slipstream for DC input.
Sanyo OS-CON SP for DC input.
Super-regulator 3 for 3.3V digital supply.
4x Sanyo OS-CON SVP for local decoupling.
Bybee Slipstream purifier for digital out.
WBT NextGen cu RCA phono for digital output.
Sontech SFRT-AL resonance control.
