4) Power Supplies
All incoming DC is converted to a high-frequency waveform and then recti ed and ltered by a choke input
capacitor lter (that is straight out of classic tube design, brought up to the latest 21st century technology).
This produces a rst-level DC bus from which all further voltages are derived. This circuit also generates a
galvanically-isolated power supply voltage for the USB input circuitry.
The digital section is powered by a bank of ELNA Dynacap DZ (TM) super capacitors of 6.6 Farad (6,600,000uF) value
in total. ELNA Dynacap DZ (TM) super capacitors have around 400x lower internal impedance (in comparison to
similar products of regular grade) and are used to avoid the typical drawback of the very high internal impedance of
common 'super capacitors'.
Individual low-noise TI LDO regulators with local LC ltering provide the nal low-noise power for all individual
digital sections. A total of six individual regulators cover clock, S/PDIF input and the digital section. The analogue
side of the DAC is supplied with ultra-low noise super-regulators based on iFi audio's custom ultra-low noise
OV2028 operational ampli er.
The USB input section has its own separate power management system with multiple regulators and ltering
operating from the galvanically-isolated voltage generated to power this section.
Higher voltages (especially for the tubes) are required for the analogue stage, which in effect operates on 60V rail
providing massive potential dynamic range. These are generated from the main DC bus and are ltered via multiple
inductor/capacitor stages based on great Elna Silmic capacitors.
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