Car stereo PC power supply mod with pizzazz

Now many have used computer power supplies to run various devices in the past, car stereo equipment included.  I wanted to do one that had a little style to it, yet didn’t break the bank.  It had to be able to fit in with a variety of décor, as I wanted it to be portable.  One could easily take my design further and equip it with ability to also run off a battery back, maybe finish the panels in brushed aluminum or even do away with my humble folding antenna and take advantage of the stereos built in relay to power on/off a motorized antenna, adding some nice visual movement to the unit.

• I started with an MP3 CD player unit that also had USB and standard input jacks to play music off every thing from a thumb drive to your average Ipod.  The beauty of this unit is that it has a remote, something I used to mock, but now appreciate. It used to be housed in my poor 80’s Tercel, before it bit the dust with a blown head gasket this fall.  30 bucks new with free shipping, love that ebay!
   
• The case came from a book shelving unit, made of MDF and finished in a red satin finish that my loving wife was willing to let me use, even though it broke up a set of 4.  The front and rear panels were completed in pine, with a neutral satin varnish.  Normally I am not a fan of mixed finishes, but I think it works in this case. 
   
• Speakers came from various sources, The center 20watt sub-woofer and resonating port came from a el-cheapo computer sound system.  The two 10watt side speakers came from Sony battery powered auxiliary speakers.  I didn’t bother with an amp, as the radio is all ready pushing out 50 watts per channel, and my low rated speakers don’t need it.  Surprisingly the sound coming out of the unit is amazing, clear tight highs, resonating mid-tones and some decent base.
   
• Grill for the front was found in a box of odds and ends, the two chrome side grills are actually trim rings off ceiling mounted fire extinguishing sprinkler heads.  With the backs cuts down a little the look awesome.
   
• The handle came off an old defunct sewing machine box.
   
• The antenna was a cheap after market product purchased to go on the Tercel and then promptly misplaced.  Its recent re-discovery initiated this instructable.  Oddly enough it lends a nice military look to the unit regardless of the colour scheme.

Note – “This is one of those creations conceived and constructed during a single night of insomnia.  Not thinking, I did not take any photos initially so this instructable will be a little reverse engineered.  Any gaps have been made up with drawings of the construction and careful labeling of detailed photos.  I recently added an antenna, and this was fully documented.”

The video below kinda sucks, waiting for my daughter to open her Christmas present, so I can borrow it!  For now this will have to do, by the way its State radio playing - So Bohemian  Grove.  Saw them last year at the Commodore in Vancouver, awesome!
 

 

 

Step 1 Supplies & Tools

This list will of course vary, the point of this is to build it into something that no one has seen before, similar to PC case modding.  But, here is what I used for supplies

• 1 mod style book case, open on both sides.  approx 18" high, 10" wide and 8" deep
• 2 3/4" thick sections of wood panel that will fit the interior dimensions of the book case to form the front and back
• 4 wood battens, 3/4" square by about 12 inches
• 2 3" mid range speakers
• 1 5" sub-woofer speaker
• 1 3" tube port - optional
• 1 functional computer power supply
• 1 car antennae - stubby works best
• 1 car stereo - best to find one that accepts a multitude of inputs and playable media
• 5 minute epoxy, or suitable strong, thick adhesive - I used alot, I found them at the dollar store super cheap, 2 for a dollar.  Normally they are 6 bucks a pack - score!
• Hot glue sticks, about a dozen
• screws of various sorts, lengths will be determined by your case choice.
• varnish or wood finish of your choosing - or perhaps au natural!

Tools used:

• Jigsaw
• Measuring tape
• Drill and drilling bits
• Circular saw
• Glue gun
• Dremel, angle grinder or tin snips - to manipulate any metal bits that need manipulating!
• Paint brush

Comments

[snyluc13]

awesome work!!! saw this mentioned on engadget which is awesome!!

http://www.engadget.com/2010/12/22/oval-bookshelf-is-the-perfect-case-for-this-diy-car-stereo-radio/

[iminthebathroom]

Thank you very much for posting this, I would not have know otherwise that it is being featured on other sites now. Makes me wonder if any of my other instructables have made it onto other sites, hmm, wonder how one could check this easily. Anyway, thanks for the positive feed back.

[el_duderino]

Any updates to using a battery to keep the memory intact? I thought I read somewhere that the memory function only requires 7v in which case a 9v battery should suffice. However, i'm not sure how to wire it.

[iminthebathroom]

That is a tricky one, though I'm sure others on this site would know. the problem being that your ground on the head unit is shared, in that its going to the power supply. You need to utilize the ground off of the battery in addition to the positive lead. Now in everything from computers to alarm clocks this is resolved as most are plug in and battery. i would ask this question on the instructables question section with a link to this instructable. It would save a lot of explaining to someone else. By the way, the stereo is what i'm listening to the radio on right now, still going strong and its on almost 24/7 since it was built

[el_duderino]

Thanks for the reply. Maybe the easier answer is to just leave my power supply (pyramid 13.8v, 14amp dc to ac converter) on 24/7 to keep the memory intact. Mine is a marine head unit, slated to live outside in my pool cabana.

[DIY Dave]

How would you wire both front speaker outputs into one speaker?

[iminthebathroom]

oh, thats an easy one, you go mono by using one positive from one speaker out put and the negative from the other speaker output. Some are also designed to utilize both positives. Usually your radio wiring diagram will include steps for wiring it mono.

[DIY Dave]

Thanks, that is easy

[Davvik]

How did you get around the 60 Hz noise with this project? I found that a lot of computer power supplies aren't filtered well to eliminate the noise in the background.

[iminthebathroom]

To be honest, i never had an issue with it - crystal clear sound. I know what your talking about though. i have found that most car stereos I have done this with have never had an issue. Perhaps its the radios own internal shielding, seeing how it is in such close proximity to other automotive goodies that put out lots of interference all ready. Or... I got lucky. I have done this 4 other time though with modern car stereos and havn't had an issue. Did this once along time ago with an old casette tape player, that was a different issue. However that was resolved with careful wire placement

[rbutler8]

Love the three oranges just chilling there :)

[iminthebathroom]

yeah, turned out. wasn't intentional though

[pedroSB]

I have one too...but mine is a box of three bottles of wine, with a sound system of a computer connected to it ... 5.1 pc system of "creative"

[iminthebathroom]

Cool, its amazing what a little car unit will power

[pedroSB]

ya...A lot of Power...when i put the radio on 20 all start a vibrate...

[mdshann]

I understand how you would use the front left and right and rear left and right for the front stereo and back surround speakers, and I am assuming you used the sub out on the head unit for the sub, but what did you do for the center channel? Where does the sound for that come from, did you just combine the two front signals into it? Thanks!

[rapidprototyping]

I FOUND A PIONEER CASSETTE DECK SUPERTUNER AND FOR FIVE BUCKS THEN ALSO FOUND THOUSAND WATT AMP FOR TEN BUCKS
NOW I WONER IF A COMPUTER POWER SUPPLY WOULD POWER BOTH
AND WITHOUT ALOT INTERFERENCE NOISES. MY CAR STEREO HAS ALWAYS BEEN MY HOME STEREO. i'M GOING BUILD A STEREO OUT OF A SMALL FORM FACTOR PC CASE AND JUST HAVE RCA PLUGS FOR SPEAKERS IN THE BACK. i CAN GET ALL SORTS STERO SPEAKERS AS ITS COLLEDGE TOWN AND AFTER GRADUATIOIN THEY DONT WANT THE LARGE STEREO TO STORE.

[bwdane]

I am powering my head unit and a 500W amp off of a 500W power supply. Mind you it has 2x12V rails with a combined output of 34A. The amp is drawing a max of 20A but I don't know exactly how many Amps the head unit is drawing. I would guess around 5A.

[iminthebathroom]

When I was younger I did the same thing and never had an issue, mind you the amp was 500 watts. It should be fine, but... Try to find a higher out-put computer power supply if you can. Think I used a 300 watt PS. These days that is quite weak, minimums these days start at 4-500 watt and many are much higher. My stereo has been running perpetually in the shop now for almost 6 months 24-7 and hasn't had an issue yet. The only thing is being a cassette player, it will consume slightly more power then a CD player, but really only when rewinding or fast-forwarding. You may also want to think about ventilation and resonance. Building it into a PC case, the reverberations of a "tin" case may not sound great, find something to stiffen it or deaden it a little

[tstarner]

Has anybody out there tried building one of these units using a 12v motorcycle battery for power?

[iminthebathroom]

Should work just fine, the only caveat being are motorcycle batteries good at being drained and recharged like deep cycle batteries? Small tractor batteries should work as well. What might really shine are the small deep cycle batteries that come with electric pocket bikes. i won for my daughter at a carnival and it is tiny. Or the 12v batteries out of wall mounted industrial emergency lights. In the end, as long as its around 12 volts and gives enough amps it should work fine

[tstarner]

Maybe a 12v battery from a power wheels vehicle would work well. I'd bet a trip to the local Interstate Battery store would be a good idea as well. That place has a lot of batteries!!

[dnutman]

Great pictures and a beautiful end-product. I'm thinking of doing something similar, but hopefully with a battery (or batteries) to power the whole system. Do you happen to know how many amps your head unit draws?

[iminthebathroom]

Hmm... Not sure. I still have the manual I'm sure lying around. I'll see what it says, it should be listed in the specifications. You might be better off looking at the spec' s for your particular radio being used though.

[static]

A nice looking compact unit, and a good instructable detailing the build. For my tastes the unit is too compact , not enough separation defeats the effort of constructing a stereo.

[arocse]

Great stuff. I've bought a 2nd-hand busker's amp & will use this as my box. One question though, do you have to reset your station presets if the unit is unpowered?

[iminthebathroom]

look 4-5 posts down, somebody is all ready updating schematics

[iminthebathroom]

sadly yes, but only for now. If you read down through the comments this is being addressed by several people. I will be working on the issue myself when I get a chance. The simplest idea would be to just hook up a tiny 12 volt battery to the "memory wire" In theory the memory circuit will be the only draw.... but in theory is a dangerous word sometimes. It does need some thought, but should be simple to rectify with all the people on this site!

[carlo$]

All you designers and builders are awesome! I have plans for my tool box now!

[asdfghqwerty]

how you connected the radio with the computer power

[tblo163]

I've built the unit and it works good,with good quality speakers,the sound quality is perfect.I have even added rainbow LEDS running off the 5volt supply of the PSU to the speakers to give it a great visual effect.However,I have a problem that you may be able to help with.The constant of the radio is connected to the 12v supply,but when the power is turned off I have to re-tune the stations and also re-enter the radio code.I am a bit reluctant to leave the PSU on all of the time.I was thinking maybe a back-up battery just for the memory might work.Does anyone know the minimum voltage the memory requires?

[pedroSB]

yes...you have to add a batery to the radio memory...and the memory its 12v

[iminthebathroom]

Hey thanks, I'll say it again, having people comment on this site helps everyone. I always tell anyone doing any of these builds to read through the comments as there is always a wealth of info

[iminthebathroom]

OH, totally know what you mean! Think about alarm clocks that have the 9volt battery for memory, that is what the orange wire is usually reserved for. The only problem I could think of is the negative ground. If when you powered up the unit would it multiply as feedback? Have to post this in the question section of instructables. Give me a couple day to work on it. Of course you could just add a small 12 volt battery and that should work fine, in theory...

[tblo163]

I'm getting in the deep end with the memory circuit.The constant supply appears to go all over the board,it supplies the amplifier ic and carries on to virtually every component.These are then turned on by the ACC circuit.

[tblo163]

I think the 9volt battery idea would work,it's worth a try.Also the installation of diodes should solve any feedback issues.I will experiment,and post the result.

[iminthebathroom]

you'll have to post some pics when your done!

[iminthebathroom]

very cool, this is the sort of thing why I love instructables!!!

[LS1Proud]

In Regards to guds777 comment below: "Dec 26, 2010. 3:30 PMguds777 says:
nice. but i think 600-1000 w are necessary, but if you build capacitor bank then your machine will get the power. At least you can crank it up a little.
But cool thou."

Most newer car stereos are rated at 200W of Peak Output. 50Wx4

These all have fuses to protect them rated at 10/15 amps.

The supply being rated for 11 amps on the 12V rail should supply plenty of power to crank a car stereo up beyond distortion. Just a little electronic theory, not bashing by any means.

[iminthebathroom]

exactly, I think guds777 response was to my slighlty confusing idea when I brought up using a High rated amp as well. Its all good, and thanks. Adds clarity to the issue. : )