Home Cinema Project
When we bought our house, one of the "nice to have's" was a room that had the potential to become a home cinema. Luckily we found a place in need of renovation, but offered value for money regarding space, so we ended up with a spare bedroom which became the cinema room.
System Design
Learning from others
I've been to friends houses who have had a stab at this, and had to use long VGA / HDMI leads with signal boosters due to the length, and to use it, they have to get a laptop out and connect it up each time they want to watch something. This just seems like hassle to me
It's also a shame when people forget about installing the audio side, and you end up listening via the poxy laptop in-built speakers.
I've seen the same oversights made by schools, colleges, and universities. It just comes down to not thinking it through first.
This approach was not for me!
I wanted reliability, user friendliness, impressive user experience, simplicity and neatness.
So I set some design criteria:
- No long cables on show
- No need to connect up a laptop each time
- Hidden / remote audio amplifier, speakers by the screen
- Remotely controlled media player device local to the projector
- Family friendly interface to keep everybody happy
- Low cost
Media sources and networking
All of our media was already held on a NAS Drive (Network Attached Storage), so the new cinema media player needed to be able to sit on the network, just as our television does.
As I'm a fan of reliably smooth, glitch-free viewing, I chose to run Ethernet cable to the media player, avoiding the annoying intermittent problems of relying on flaky WiFi.
For future-proofing, I also added the option for a TV aerial in case I ever want to add a TV tuner to the setup.
Wiring design overview
As we were planning to renovate the house, it was an ideal opportunity to install wiring in the ceiling spaces and walls for the home cinema as part of the bigger renovation project.
At the projector location the following was needed:
- 2x mains power outlets (one for projector, one for media player)
- 1x Ethernet socket
- 1x TV aerial socket
- 2x RCA / Phono sockets for audio L/R
Audio Wiring
Fortunately above the screen location, we had a small loft / attic space, so I chose to locate the audio amplifier here.
The coaxial audio phono cables needed to run from the projector location through the ceiling cavity, to the hidden audio amplifier location to in the loft space. There are then speaker cables from the amplifier that run down to the cinema room to the speaker locations.
As part of the house rewiring, I had the electrician install a switch in the cinema room which remotely controlled a mains socket in the hidden loft space, hence, remotely controlling the power to the hidden amplifier. I selected a switch faceplate with neon indicator to remind you to turn the power off after use.
Selecting The Equipment
As with all of my projects, this was being done on a low budget - and ended up costing about the same as an average LCD television!
Media Player
The £35.00 Raspberry Pi3 had just been released, so this is what I selected as the media player. It offers much better performance then it's predecessors, mainly noticeable when going through menus. It has a £4.99 SanDisk 8Gb Micro SD card, £1.99 minimalistic case and at uses an old Blackberry phone charger as it's power supply, that I had lying around.
Projector
The selection of the projector had little research behind it, as we got lucky with a Black Friday Deal from Currys. An Optoma HD141X Full HD (3D) Projector for £399.99. Fortunately it's quality is great. Projector mounting bracket was £14.99
Screen
The screen selection was based on the width of the wall at the end of the room, it needed to fill the space available, and fully cover the window behind it. I found a Homegear motorised screen 16:9, 2.6m x 1.5m, (120" corner to corner). It had average reviews, as the screen tends to ripple, but it was around £89.99, so for that money, you can't argue. The ripples are only really noticeable during wide panning shots.
Audio
I bought another pair of my favourite speakers second hand from ebay, a pair of KEF Coda 7 bookshelf speakers for £35.00. The wall mounted speaker brackets were a bit pricey at £29.95 though.
The amplifier is one I've had since about the year 2000, even then it was old. A 1993 Marantz PM-34SE, I bought it second hand for £15.00 back then. It's probably worth more now as a classic!
I added speaker wire binding posts to the front of a standard blank 1 gang faceplate. All four posts cost £6.45, and the blank faceplates were £0.43 each.
Remote control
I bought the nice OSMC RF remote control for £16.99 - a nice simple family-friendly interface.
Total Cost
£644.75 - plus a little for the wiring installed in the house, faceplates etc.. perhaps another £10.00 or so.
Installation
Electrical Faceplates
The projector & Raspberry Pi connections installed as part of the house renovation, from left to right: Audio to hidden amplifier; Ethernet from main switch; TV aerial from loft; Double mains outlet.
I custom made faceplates for the speaker connections just by installing binding posts to blank faceplates.
Wiring up
The Raspberry Pi sat nicely on top of the projector, a short HDMI cable used to connect them together. Audio was taken from the projector, as it's output is better quality than the Pi. A short piece of trunking carried the cables from the wall to the projector.
KEF Coda 7 speaker installed beside the screen and wired to the custom faceplates.
Homegear Projector Screen Motor Control Modification
The Homegear screen came with a hardwired controller, plus IR remote control to operate it up / down. This unfortunately looked a bit messy, needing to be plugged in in the cinema room, and it meant ANOTHER IR remote control, when I wanted simplicity.
So, I found a solution to tidy it up.
As I already had a mains socket remotely controlled in the loft space above the screen, it occurred to me that I could use this signal to lower the screen when the amplifier is turned on, and raise it when the amplifier supply is turned off. This of course would need a separate supply to lift the screen it when the amplifier power is removed.
The screen's connection to the supplied control box consists of one Neutral wire and two Phase wired. Energising either Phase wire will make the screen move in either direction until its internal limit switches stop it travelling. This interface made the design nice and simple, just using one relay:
Operation
I chose OSMC as the operating system (a fork from Kodi / XBMC), and used the OSMC remote.
Review
OSMC runs very nicely on the Raspberry Pi 3, is easy to set up, and the OSMC remote worked straight out of the box.
The remotely controlled amplifier works really nicely too, the red indicator light on the switch was a good call, as when you go to leave the room and put the lights out, it's obvious when you've left the amplifier on.
I'm really very pleased with it as a system, as it's achieved all of the criteria I set out to achieve by thinking it through first. It's neat and tidy, gives an impressive experience, and most importantly, my family are happy using it, which means I'm not getting "tech support" calls to play a film!
The only further improvement would be to somehow get rid of the ripples in the Homegear screen, or one day replace it for a better quality one.