Most of the parts were old (at least when I started):
1. Old automotive amplifier found in the garage. Eventually, as they project grew, it got upgraded with a second amp, the original one pushing 440 watts on two channels ( powers the subs) and a 1000 watt with built in crossover powering the midrange and highs.
2. Power supply from old pc.
3. An abundance of old speakers. I originally had 2 old 15's from a club speaker I got from my sister (pictured). I also had a pair of 4 inch mids scavenged from a Sony home stereo, 2 two inch tweeters from some pc speakers, and a 5 1/4 Sony, scavenged from another home stereo speaker.
4. a raspberry pi ( I started with a b+, but upgraded to the 3 because of the integrated Wi-Fi)
5 Wood. Lots of wood. Most I had, some I bought. And fasteners (screws, wood glue etc.)
6 Some old el wire. I had made some Halloween decorations using it the year before, and used the remainder for lining the subs.
This was phase one. It had no style. Just good sound. But both would soon improve.
The picture is below.
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Step 1: Power Supply Modification
The power supply needs to be modified which is simple. On most ATX power supplies, you will cut the green wire and a ground wire coming off the main longer to the board. There are several sites on the web that provide detailed instructions on how to modify a power supply too power a car amp. Just keep in mind yellow wires are 12v, and red ones are 5v. Use the yellow and a ground one to power the amp. Use the red and a ground for the pi. I cut a Usb cable, and connected it to the power supply wires inside (red and black) to the 5 volt rail of the pc power supply, and plugged it in to the Pi. Eventually, I put a switch in the line so I didn't have to always go in the back and turn on and off the psu.
Step 2: Cutting Holes.
Of course, you may not have the same number and size of speakers as I do, or you may not make it the same size I did. But what you will need is a hole / circle cutter. I used a Dremel with the hole cutting attachment. For my larger ones, I cheated, and just traced the speakers, because the Dremel hole cutter stops at 12 inches, and my subs are 15's. Keep in mind to cut your holes the same size of your speakers inner dimensions.
Step 3: Assembly
Be sure to tighten all of your screws well. Vibration noise is your enemy. I also use great stuff in the crevices and any small holes I made, but due to design changes were no longer used. Initially I had the amps on the inside, but they vibrated against the wood, plus I wanted to access them to be able to easily change the gain and adjust the built in crossover.
Also, at my wood joins, I not only screwed but after final assembly, COMPLETELY disassembled it and lines each wood join with glue and then screwed it all back together.
Another point of vibration (for me) was the plexiglass. My solution was increasing the number of fasteners (screws), and putting adhesive on the back of the plexiglass. If you use think about using plexiglass...the base is plexiglass covered, but I finally got smart, and switched to lexan for the top with the display and LED's. I had broken 2 sheets, and though I was able to reuse 80% of it, and put a delay in my personal deadline. I recommend lexan I used 1/8 inch thick for both, but I would think less vibration would come from a thicker cut, but:
A: it is considerably more expensive for 1/4 thick sheets.
B: Heating it is already an arduous task, and a thicker cut would take a while.
Speaking of hearing it for bending, I came up with a neat little trick to speed it up.
A long light steel out heavy aluminum pole and a heat gun along the line you want to make your bend, like pictured. Once the pole is hot, it bends like rubber(not the lexan, that is a beast to bend with heat. A bend brake would be the way too go if you choose to use lexan. It took me two hours to bend the tinted 48x24 inch sheet! And then I got smart (again) and drilled a hole through the lexan, and ran an old cat5 cable through it and heated. the lexan at the bend point, while pulling on the rope, with the bend point clamped to a piece of wood. Fairly long parentheses note, eh?).