There is still 3 options for different locations for pc-drawer and amplifier + ups. I can post here the current setup I have on my prototype. It works fine but it would be easier to deal with all the cables if the amplifier would move together with pc OR neither of those would move. In that case the front panels would be only doors that opens vertically. I will have to decide soon the first product version structure.
Note! situation without processor fans. This setup never actually tested in practise.
--> power moved and MB "tilted":
These are not pictures of final version. Just some pictures of different test setups.
Air comes in via the "labyrinth" and continues to sound absorption tunnel and finally comes out from the other end of the furniture.
Computer is very cool and silent with this setup. Amplifier may need active cooling, alltough I have had the entire setup powered on 24/7 for almost a year now with out any problems. The amp might move downstairs next to the pc unit...
Using passive components is absolutely out of question, because the idea is, that this "furniture" does everything. Including the gaming (youtube link)
and multitasking etc. Sound issue is solved by understanding the difference between sound absorption and sound isolation and using space enough to absorb the sound. Isolate the noisy parts airtight (rule no. 1 in isolation) + use rubber fixing to isolate the vibrations. Make the cooling air flow through a long and twisty tunnel that is coated with sound absorbent material.
Also make sure that the hot air goes straight out of the area that needs to be cooled and never circles back.
IMO ALL the current commercial htpc cases that I have seen are lousy, because the back panel is wide open - no isolations / absorption so they just can´t be silent if active cooling is used.
(vid. using HTC Desire to control the system