The glossy plastic is mostly transparent. There is a layer of dark
material applied inside to block unwanted light. However there happens
to be blank spot above the source knob and that is where I installed the
green LED.
The LED needs a power-on signal. Without a schematic, I found no test
point that could be tapped. But there happens to be a transistor power enable on the
power-on touch board seen here in the lower left corner of the upside
down 3045. I carefully soldered a 30 awg solid wire (white) which will
activate the LED.
The green LED and related components are soldered on a PCB fragment
which is tacked to the top of the source selector using glue gun thermal
glue. In addition to the power-on signal, which needs to be buffered by (R2), the PCB needs 3v3s (orange to D1) and gnd (green) from the mainboard header.
Cover Removal:
Now we open the case. Notice there are rectangular tabs around the
inside edge which are to be caught by tiny fingers on the top cover. I
pried the cover partially open with a spackling tool to feed in a
temperature sensor. That was a temporary task to measure the operating
temperature (52C). An external fan is needed because heat is the enemy
of semiconductor electronics.
Removing the cover completely is difficult because the means of
attachment are invisible. For example, the blue analogue input module is
screwed to the top cover and also to the rear metal panel (light grey)
which is covered by a thin black metal plate which has the connector
labels. The black plate has three screws to align it but it hides six more that prevent opening the case.
The two plates are joined by a sticky, tarry substance. Separating
these two requires intuition and determination. But after the internal
work is done, it can all be assembled without apparent damage.
Cooling:
The D3045 has a few tiny holes in the rear panel for ventilation. There is a narrow grill in the top and bottom covers which is only for the metal box of power line components. It does not cool the Hypex module which is attached to the box by a metal bracket. This flat bracket is not a good heat conductor. The thermal resistance of the plastic case contributes to the excessive heat problem. If a plastic case feels warm know that the inside is hot.
The Hypex FAQ insists never operate the amplifier without a heatsink. See questions 9 and 10 for explanation.
I have a rented PVR which has a plastic case with tiny holes providing very little ventilation. It gets hot like the D3045. In recent days it randomly ignored the remote or got stuck on one channel. Finally it bricked and needed replacement. Never buy an amplifier in a plastic case. It is a potential hot brick.
Heat is the enemy of semiconductor electronics.
There is internal space where a fan could be installed in the D3045 but that would
require drilling holes in the glossy plastic. Instead a fan placed
behind the unit will lower the internal temperature and keep the cover
near ambient. I attached the fan to a spare pcb to prevent it from
tipping over when positioned between the wires.
The class-D concept for audio amplification was not a serious contender
for many years. Now NAD and Hypex have advanced the technology. It
looks superior from the specification numbers even though audiophiles
may shrug. The D3045 has the power but the case design is so compact
that usability is compromised. However, I am satisfied with the
simplified power-on indication and improved cooling.
Right To Repair .. proposed legislation may lead to better designs.
