Our modifications start with a series of upgrades to the power
supplies, upgrading bypassing & decoupling capacitors, upgrading the
generic regulators to ultra-low noise types, upgrading the analogue stage.
Starting with the incoming DC supply and bypassing for
the voltage regulators we upgrade the capacitors. The
input and output bypass capacitors have a ripple voltage (seen as noise on the
supply voltage) proportional to the ESR of the capacitor. Highest grade, low
ESR capacitors ensure lowest noise across a wide frequency range; we use
Panasonic FC & Sanyo OS-CON for best results.
The WM8741 DAC has both 3.3V (digital)
& 5.0V (analogue) power supplies, here we replace the decoupling for
analogue supplies with the excellent Elna Silmic RFS capacitors, and OS-CON are
used for digital decoupling.
A total of 6 voltage regulators are
enrolled in the rDac for the 3.3 & 5.0V supplies. The task of the regulator
is to remove ripple (noise) and provide a regulated, stepped down DC voltage to
specific circuit blocks. The latter is achieved, but the industrial standard
regulators have higher than desirable noise for audio. We replace all key
regulators with the Super-regulator 3 boards, a discrete regulator with
ultra-low noise, low impedance output. Super-regulator
3 has a very high noise rejection capability and provide circuitry with a much
cleaner current, thus enabling the DACs to express their full dynamic range.
rDac Linear Power Supply
The factory supply wall-wart supplied
with the rDac is a limiting factor to performance. We highly recommend
upgrading the wall-wart supply to the TeddyrDacPS
Power Supply, a very high discrete regulator supply based on the
SuperTeddyReg circuitry.
Arcam rDac Level-1 Upgrade
1x Panasonic FC capacitor for DC input bypassing.
1x Panasonic FC capacitor for 3.3V digital regulator output bypass.
2x Panasonic FC capacitor for 3.3V digital regulator output bypass. (WM8805)
2x Panasonic FC capacitor for 5.0V analogue regulators output bypass.
3x Elna SILMIC RFS for DAC analogue decoupling (WM8741)
2x OS-CON SH for DAC digital decoupling. (WM8741)
4x Elna SILMIC RFS for analogue stage decoupling.
1x Super-regulator 3 for 5.0V analogue output stage.
Arcam rDac Level-2 Upgrade
1x Panasonic FC capacitor for DC input bypassing.
1x Panasonic FC capacitor for 3.3V digital regulator output bypass.
1x OS-CON SH capacitor for 3.3V digital regulator input bypass. (DAC &
Logic)
2x Panasonic FC capacitor for 3.3V digital regulator output bypass. (WM8805)
2x OS-CON SH capacitor for 5.0V analogue regulators input bypass.
2x Panasonic FC capacitor for 5.0V analogue regulators output bypass.
3x Elna SILMIC RFS for DAC analogue decoupling (WM8741)
2x OS-CON SH for DAC digital decoupling. (WM8741)
4x Elna SILMIC RFS for analogue stage decoupling.
1x Super-regulator 3 for 5.0V analogue power supply (DAC).
1x Super-regulator 3 for 5.0V analogue output stage.
Arcam rDac Level-3 Upgrade
1x Panasonic FC capacitor for DC input bypassing.
1x Panasonic FC capacitor for 3.3V digital regulator output bypass.
1x OS-CON SH capacitor for 3.3V digital regulator input bypass. (DAC &
Logic)
2x OS-CON SH capacitor for 3.3V digital regulator input bypass. (WM8805)
2x Panasonic FC capacitor for 3.3V digital regulator output bypass. (WM8805)
2x OS-CON SH capacitor for 5.0V analogue regulators input bypass.
2x Panasonic FC capacitor for 5.0V analogue regulators output bypass.
3x Elna SILMIC RFS for DAC analogue decoupling (WM8741)
2x OS-CON SH for DAC digital decoupling. (WM8741)
4x Elna SILMIC RFS for analogue stage decoupling.
1x Super-regulator 3 for 3.3V digital power supply (DAC & Logic).
1x Super-regulator 3 for 5.0V analogue power supply (DAC).
1x Super-regulator 3 for 5.0V analogue output stage.
