Boat Audio/Video System with a Mac Mini

My boat is a 40' Carver. It has a salon inside with 2 bedrooms and a bridge on top. There are effectively 3 zones for audio: Bridge, Salon, Aft bedroom. The front bedroom is not wired and it's probably not necessary.

My main objective was to eliminate the need for a typical car headend unit. This works great in a car where you are always within arms length, but it's more of an excuse in a boat as far as I can tell. I elected to have a MacMini as the 'headend' this presented several challenges as The MacMini and the 24" Samsung LCD are both AC Powered. I also decided to use a Clearwire modem for connectivity to the Internet. It's particularly nice because I'm connected anywhere my boat travels on the lake. It's plugged directly into the Ethernet Port on the Mac Mini and I have the MacMini setup to act as an access point sharing the Clearwire connection with any other laptops or iPhones that care to connect via WIFI. Sweet!

So, while the Mini (2 amps), Monitor (.5 amps) and Clearwire Modem (2 amps) are AC powered, the marine grade amplifier is DC powered. I ordered a DC breaker from Carver for my DC Panel. It's a short run from the DC panel to the entertainment center. I ran the positive and negative connections to separate distribution strips. Then I connected the inverter (I chose a 600W inverter - 5A at 120V) and the amplifier to those strips. In planning for this, I determined that without a headend unit, I was going to have a problem managing the power of the DC Amp. I decided that trying to remember to flip a breaker to turn the Amp on and off would result in a dead battery or overheating. With most car installations, the headend unit turns the amp on with a 12v remote control wire. Since I have no headend unit, I had to find an amp that would turn on by sensing audio on the RCA inputs. I found one, Kicker MX350.4 Marine. Happy Day.

Now the Mac Mini has a small, flaky mini jack as an audio out. I found a really cool device made by Behringer U-CONTROL UCA202 USB-Audio Interface for around $30. It plugs into the USB and outputs RCA, headphone and Optical. Absolutely amazing for $30! An added bonus is that there is no driver installation required on my Mini. Just plug it in and the device shows up as an output option in the Sound Preferences.

Now I've described the full path to get the power to the hardware and the audio to the amp. It's a 4 channel amp and I have 6 speakers. You may be thinking "Bill didn't think this through". Ah, but you would be wrong. I decided that I did not want to manage relative volume of the 3 zones through software so I found a piece of hardware to handle it. Managing zone levels in software is just not responsive and flexible enough. Sometimes it's easier just to tell someone to turn the knob down.

Another interesting problem to resolve was the amp power. I needed to use a DC powered car amp. I looked around and finally found the Kicker ZX series. Most amps are turned on with a remote +12v wire. This amp has a selector to enable power-on when it senses audio input on the RCA jacks. It's exactly what I was looking for! Now, it automatically shuts off when the mini stops sending sound.

I found the Niles Audio SSVC-4 Speaker Selector with Volume Controls. This is a 4-way speaker distribution box with separate volume controls and on off switches for each zone. I'm assigning 3 of the volume control to my 3 zones. I bridged the 4 channel amp to turn it into a 2 channel amp and ran those wires to the input on the Niles Device. I then hooked each zone (bedroom, salon, bridge) up to the Niles Zone Controller. The Niles requires no power so that was easy.

So, that's it! My Mac Mini sleeps after an hour of inactivity and the monitor sleeps after 1 minute. Interestingly, boxee has a 'suspend' setting the sleeps the mini...very cool. The amp powers down after sensing no audio after 30 seconds or so. The best thing about this setup is that there is no loss of continuity when I turn off shore power since all pieces of gear run off the house batteries. My house batteries have dedicated chargers that run when the engines are running and when the generator is running, and according to my calculations, it would take 15 hours of continuous use in order to run the house batteries down.

Software: The Mac Mini is running iTunes for music and Apple made a great iTunes remote application for the iPhone so I can manage music, including volume from anywhere within WIFI range of the Mac Mini. For video, I am using Boxee.tv. It's in alpha now, and is getting better every day. It connects to many video web sites including CNN, CBS and Hulu and streams video. It also plays basically any format of video you can imagine and works cleanly with the Apple Remote Control. For HD Channel over the air I am using Elgato's EyeTV Hybrid. It works great but I wish that it integrated into Boxee. That would truly rock.

The Mac Mini has a built-in DVD player and Boxee can play from that as well. Looking skyward ala Jon Stewart "Give us BluRay....damn you Apple...". I could play music from the boxee interface, but Apple really nailed it on the iPhone remote application. I'd give anything if Boxee could emulate that for movies/tv/torrents. UPDATE: I found 2 programs that seem to work, although I'd say that Xmote works best. It's $3 and controls any XBMC server. Since boxee is based on XBMC, all I had to do was turn on the web server and I set the port on both boxee and Xmote to 8080. You also need to configure the IP address of the boxee machine in the settings area of the iPhone where Xmote shows up.

Another critical piece for the Mac Mini is a way to have a trackpad. I bought a bluetooth keyboard, but using a mouse with an entertainment center sucks. Air mouse for the iPhone works incredibly well! It's well worth $5. It also acts as a pretty usable keyboard in a pinch. Now I can walk on my boat, wake the Mac mini and have music and or video in a matter of seconds controllable at various levels in various zones. The cost on the entire setup including the Mac Mini and monitor was about $1400. The monitor was $500 of it and the Niles device was $250 and the Amp was $200. I hope this help someone who is struggling with a similar situation. Now I'm looking for standard round speakers that have extra bass response, because I don't want to go through the hassle of installing a separate Subwoofer.

UPDATE: Looks like my inverter was only good for about 5.3 amps and I think I was drawing close to 5.3 amps. I had an easy solution. The Clearwire modem AC/DC brick provides 12V DC to the Clearwire modem. I tested the output from it and it was pushing around 15.5V. The battery bank on my boat varies between 13.5 and 15.5 V so I decided to lop off the brick and I wired the clearwire modem directly into some spare terminals on the distribution strips. I was very careful to make sure that the polarity was correct. The tip (inside) needs to be positive. Make sure you test it with a multimeter to avoid frying the Clearwire modem.

One piece that I had given up on was having the ability to sync my Laptop music library with the Mac Mini. Since I keep my library organized solely on my Laptop, I want to have the Mini on the boat reflect exactly that without exerting any additional effort. A simple Google search revealed Syncopation. It's $24 and it just works. There are many options and I was able to make my Laptop the master and the Mini the slave.