Storing music on a hard disk is not a new concept,
companies like Olive Audio’s 4HD music server has been available for around 5
years. With the inset of higher
resolution movie formats, namely, Blu-ray, a similar approach has been adopted
by Popcorn Hour with the C-200. Described as a Networked Media Tank, the C-200
is a versatile unit which allows you to store digital media on a Hard Drive,
accepts media on a flash drive, and has an option to add a Blu-ray drive.
The C-200 like any other network media players
performance is largely influenced by the quality of AC power supply, DC
regulated supplies, noise filtering and clock jitter. By removing noise on the
DC supply lines, regulated power supplies, as well as removing jitter, we have
been able to significantly improve movie picture quality, movie sound, and the
quality of digital audio via the RCA coaxial output.
The modifications have been categorised as
follows to suit individual set-ups;
HDMI Only
Upgrade: - These
upgrades are perfect for the user who wants to connect the C-200 to a HDTV, AV
receiver, etc.
Full Player Upgrade:-Optimises all audio & video outputs.
Digital
Output Upgrade:-Improves the RCA coaxial output for use
with a separate D-A Converter.
The upgrade starts with improvements to the power
supplies. Devices like the C-200 are low voltage designs, but the higher levels
of processing complexity mean that power (current) is high and demand for low
ESR greater. This is because as current increases, so does ripple voltage
(noise) so lowest ESR capacitors must be used to keep noise to a minimum. We
replace capacitors in the SMPS with Rubycon ZA/ZL type, with higher ripple
current and lower impedance than any other wet type electrolytic. The output of
the SMPS is brought to the main PCB with an ATX connector. The input bypass
capacitors on the main board are upgraded to Rubycon ZHL type for the 12V and
5V supply lines. These supplies are then regulated down to 5V & 3.3V for
the video and audio circuits using generic 3-terminal regulators. We
replace these with “Super-regulators”, this discrete regulator provides
excellent Power Supply Rejection (PSRR) across a wide bandwidth in conjunction
with an ultra-low noise, low impedance output. The associated regulation bypass
and local decoupling capacitors are upgraded to Sanyo OS-CON SP to ensure the
best noise filtering.
For the digital output upgrade we fit a Bybee Slipstream purifier for
the digital coaxial output. During
transit through the Quantum Purifier, quantum noise energy is stripped off the
electrons, streamlining their flow through ensuing conductors. Unwanted quantum
noise energy dissipates as heat within the Quantum Purifier rather than
emerging as a layer of contamination residue over the digital signal.
As standard we upgrade the master clock for the SMP8643
media processor. The 27 MHz clock is derived from a logic gate inside the
SMP8643. The 27 MHz crystal connects across the input/output of the gate to
form a Pierce oscillator. The Pierce Gate receives noise from the hundreds of
switching processes of the SMP8643 processor which is transferred to the output
of the clock signal. We replace the Pierce Oscillator with the
Superclock 4. With the SMP8643 referenced to an ultra-low jitter external clock
jitter is significantly reduced with marked improvements picture and sound
quality.
