How to Build a Stereo Cooler Part II
I decided to take the next step and install a receiver in my cooler so that I can control the audio from outside the cooler without having to get inside and mess with my iPod. I chose the Pyle PL98M4 for $100 as my receiver, mostly because I knew that I wanted to play mp3 from a card rather than CDs, and the Pyle unit is “mechless” in that it doesn’t have any moving parts. This should make it more reliable and eliminate the risk of water penetrating a CD slot. I was disappointed that the unit does not have an REM output that would allow me to turn the amplifier on and off from outside, but otherwise it’s a good unit and the LCD display is convenient.
I’m using the RCA outputs and not the built in amplifier because I already have the 400W Jensen unit. I don’t know whether the receiver’s amplifier draws the same current if no speakers are connected, so I’m a little concerned that it will mean less battery life overall, does anyone know? If it is drawing lots of current then in a future project I will install more speakers – we might as well use the juice rather than waste it!
To protect the receiver from water, I purchased a universal splash guard. It’s not water proof, but should be good enough to protect the unit from a brief dunking if the worst comes to the worst on the river. I had to install it on the back of the cooler due to lack of space on the front. The water resistant seal provided provides a convenient template for cutting into the cooler.
Having done this a few times now, the best technique I’ve found so far to remove the foam is to cut a grid pattern, then pry out the foam in cubes. Once you’ve got most of the foam out, you can simply cut through the inner panel from the outside. You need to make the hole on the inside about 3/4 of an inch larger on the top side to accommodate the lid of the splash guard. A sanding block comes in handy for smoothing and shaping the foam.
The receiver comes with a caddy that you’re supposed to fix into your car and then the receiver can slide into it easily. Push the caddy in from the font and then fold the metal flaps out to grab the body of the splash guard. Given that we’re putting it into a cooler there’s not much support for the caddy, but fortunately we can use the splash guard itself to secure the whole apparatus to the cooler.
Don’t try to install the splash guard and caddy with the receiver already in it, it would be much more difficult.
This is the view from the inside. I used the nuts and bolts provided with the splash guard and washers to secure it to the panel. I marked and drilled small holes in the panel to slip the bolts through, and cut out foam to get at the nuts from the inside to hold them while I tightened. I would not do it the same way again – it was a major hassle fitting and tightening the nuts. Instead, I would buy longer 3″ bolts, long enough to pass through the entire wall of the cooler. Then it would be easy to just drill through the entire cooler wall and secure cleanly on the inside.
Now to wiring. I already have an amplifier hooked up, but if you’re using just the receiver for amplification then you can use the appropriate steps from my initial post on building an ice chest stereo to set up and wire the speakers, switch, and power supply. As I said before, there is no REM wire to control the amp, so we’ll need to continue to rely on the switch to power the system on and off. It’s important that we can turn off both the receiver and amp at the same time, because they’ll quickly draw down the battery if left on even with no music playing.
The instructions provided with the Pyle receiver were completely worthless – the only useful information is in the wiring diagram printed on the unit itself (see above). I have no idea what “Memory B+” means, but a little testing showed that this is the +12V power line that drives the unit. “Ignition Switch” is the signal line that triggers the unit to turn on. We need +12V on both these lines, but the real current is drawn on the confusingly named Memory B+ (can anyone explain what this means?) [Edit: Jacob F pointed out that Memory B+ is most likely to keep the clock and settings alive and that Ignition powers the receiver - he's almost certainly right]
The solution is to put the Ignition Memory B+ line on the same circuit as the REM switch. We also need to connect power, so I opted to crowd everything on the amp connectors, doubling up the +12V and GND. This looks messy, but is screwed down tight and secure. Both the amp and the receiver are at +12V, but the switch simultaneously gates power to the receiver ignition and amp REM lines keeping them on or off together.
I also took the opportunity to secure the switch to the side of the cooler. I used a metal strip that happened to come with the receiver, with a nut and bolt and wood screws. I used 3 screws just to be sure because the plastic wall is flimsy.
And here is the finished result.
The Pyle receiver will accept SD and MCC flash RAM loaded with MP3s, and allows you to navigate through one level of folders. I was disappointed that it didn’t handle the track names better when browsing for music, but I usually just listen to playlists on the river anyway, occassionally skipping through tracks, so it isn’t a major problem.
Well that’s another afternoon project completed successfully! Next time I might add some smaller speakers to the front of the cooler to get more of a “surround sound” and take advantage of the additional amplification in the receiver. Comments and feedback are welcome as always!
June 2nd, 2010 at 8:36 am
My setup includes this amp: http://www.sonicelectronix.com/item_11596_Boss+CX350.html
along with two 5 inch Pyle speakers…no head unit, just plugging the ipod directly into the amp. Was thinking of adding a subwoofer. How would I connect it…just wire it to one of the two unused speaker channels? (its a 4 channel amp but i only have two speakers hooked up at this point)…or would i need some additional hardware? thanks everyone…
July 17th, 2010 at 6:29 pm
Saw one this week at Port Aransas. The guy had used a trolling battery and had that hooked up to a small trickle charger that he could charge with AC in the garage when not in use. He had also mounted a solar panel from Fry’s on top of the cooler and had that wired in to charge the battery as well. Finally, he replaced the wheels with some big pneumatic tires from Home Depot. His wasn’t really made to float the river but it was sweet for the beach.
Thanks for all the info and photos. Will definitely build one of these soon.
September 7th, 2010 at 12:36 pm
can you show me the rca hook ups on the amp and the stereo please i hooked it up to what seemed right but got a real low sound if any at all, dont know where the rcas go, thanks and appriciate your help, Ronny
January 8th, 2011 at 10:41 am
If your radio doesn’t have a “REM” output, you could just use a + speaker output wire instead.
February 2nd, 2011 at 5:57 pm
Although this seems to be a fairly simple build, I have a couple important questions! How long does this battery play for? Because I am planning on using mine for Mardi Gras, both at the parades and bringing on our float as our sound system, I will not be utilizing the water proof materials but I am using the ice chest for easy transportation, how many or what type of batteries should I use to last approximately 12-14 hours? And how many or what type of amplifier should I use? Lastly, because we will want to cover a lot of area sound wise and I need speakers that are not mounted in the ice chest, what kind of speakers would I use? I am assuming I can drill two small holes in the ice chest to run the speaker wire from the radio to the standalone speakers? Any suggestions on my many many questions?
February 3rd, 2011 at 6:36 am
Kim, yes you could do this. If you don’t want speakers in the cooler you can just use regular bookcase speakers. For 14 hrs you will likely need 2 mower batteries or 1 full size car battery. Get a ‘deep cycle’ one.
March 26th, 2011 at 8:26 am
Hey Keith, Learning alot from you. I do have one question regarding the head unit. What did you use to ground the it? Or, do you even need to ground the head unit? I am working on my first build. My goal is to create a lightweight, more portable cooler for floating. As anyone who has floated the Guat knows sometimes the campsites don’t drop you off in the best of places…even for a rolling cooler. Below is a list of components I have already purchased for the build, let me know if there are any issues with what I am using, as I am an extreme novice:
- 6.5 IN Infinity 225-watt Marine speakers
- Reno Series 240 watt 2 channel amp
- Pioneer DEH 2200UB Reciever
- Battery Float Charger (to charge the battery using a wall outlet)
Will the head unit be able to turn off/on the amp?
I know this is a long post…I just don’t want the system to melt the cooler or components to burn out.
Thanks!
March 26th, 2011 at 11:45 am
Adam, I’d recommend building with just the receiver first. It might be loud enough for you, and will be lighter, draw less power and generate less heat. You could use a small sealed battery from an electronics store (eg Fry’s) and truly have a small light system. If you want more volume you can add the amp later. On grounding, in car audio, ground is just the circuit return to the battery negative terminal. Usually this will be the car body itself. It’s not like grounding in light circuits. Best of luck!
April 19th, 2011 at 11:08 am
im going to put an 8 inch sub on mine am i going to need to have an amp also and if so how many watts
April 21st, 2011 at 8:59 pm
How would I go about adding a car stereo?
April 27th, 2011 at 1:26 pm
Hi Everyone, I just bought PYle marine speaker/amp set from Amazon and hope this works well for only $106. Take a look, it seems to have almost everything you need. This is my first build and I plan to be on the river for 6-8 hours.
http://www.amazon.com/Pyle-PLMRKT4A-Channel-Waterproof-Amplified/dp/B003GSLDUY/ref=sr_1_2?s=electronics&ie=UTF8&qid=1303935662&sr=1-2
I have 3 main questions:
First, what is the ideal cooler qt size, is 54 Qt good??
Second, would a 12v battery be good enough or do you think i should get two or a car battery?
Third, any suggestions on speaker placement, should i do one on each side, front back, top………..
Thanks, I am glad I found this site.
May 4th, 2011 at 7:18 am
another question, I have an 18v cordless drill battery, does anyone know if that would last long enough?
May 8th, 2011 at 8:22 pm
Needs to be 12 volt to power the car audio equipment.
May 9th, 2011 at 10:47 am
Hey Keith Im curious about how you secure this setup to a tube. Is it very top heavy. I know a picture is alot to ask but that would be ideal
May 9th, 2011 at 11:16 am
Steven, you need to get a tube with a bottom. The cooler I used fits snugly in the ring, resting on the bottom, and is extremely stable. I’ve also been using bungee cords to tie it down, but that’s probably only really needed for a small or tall cooler where there’s a risk of it moving around.
May 9th, 2011 at 4:42 pm
Thanks.
Alot!
May 12th, 2011 at 3:49 pm
I should have my build done this weekend. I will try and post some pics. Thanks Keith for all the tips.
June 30th, 2011 at 10:14 am
Hey Keith- I have built mine with 4 speakers and an Alpine Head Unit and Kicker Amp using a Die Hard Tractor battery. I’m not getting any power to anything but switch. How do I wire the Radio/Amp to battery with ON-Off switch??? Any help–Thanks