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For a couple of hundred dollars, the builder can frame and put a door to turn the niche into a closet.


I think you need a cheaper builder.
You can get all sorts of door types at places like Home Depot but if smaller closet doors won't fit, a frame and custom door is very easy to DIY. Now if you are going with something like glass on the front to work remotes through it, that's a bit different. We have two 22" french doors with glass at the opening of our media room so i know you can get doors that small, non custom.

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The closet might help with noise from the electronics


The loudest component i have right now is my dvdp. I can hear it whirring away. This is one small reason i may consider buying a more expensive dvdp, to get a more quiet transport.

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Do people who have their electronics in a niche or out in the media room wish it was hidden away in a closet? Do those who have their gear in a closet wish they had more direct access to their gear?


I prefer to show the equipment but yes, a clean look is necessary (nice rack, organized cables). It just takes some patience and time in bundling all the cables together with ties, ropes, elastic bands, gum and sticking them into conduits or cable runs on the back of the racking, but the end result is worth it. I've seen some closet style equipment before but rarely completely enclosed. Heat can be an issue (and hence installing HVAC specifically for that small area a pain) but constant access to the dvdp or any other component is a second reason to leave them 'open'.
That's my four cents.

"Those who preach the myths of audio are ignorant of truth."