Picture of Back Woofer
How to create a simple amplifier from scavenged car stereo parts to put sound into a backpack
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Step 1:

Picture of
I didn’t want to spend a lot of money on parts, so budget wise most my parts were scavenged from a car stereo a friend was going to throw into the trash. I made this so I could have a more portable and convenient boom-box type back pack.

Like this scavenged TDA1558Q from that stereo. (On the heat sink)

I did something like this before by taking the set up out of a gaming chair with the speakers, inputs, and volume control, that was nice but it didn’t have the bass that I really wanted from a portable stereo. My improved version has the bass that I was looking for and has the volume control from the audio input device (i.e. Mp3, ipod, iphone, etc.).

Step 2:

Here are the components that I used:
• TDA1558Q (x1)
• 1k Resistor (x1)
• Red L.E.D. (x1)
• .1 uf Capacitor (x2)
• 2200 uf 50 V Capacitor (x1)
• RCA/Headphone cable (x1)
• Suitable Heat sink (Medium sized) (x1)
• Band-pass Filter
           22 ohm 5 Watt Resistor (x1)
           68 uf 35 V Capacitor (x1)
• Enclosure (x1)
• Wire
• Solder
• Proto board
• 4 ohm speakers (x2)
• 12 V Battery pack (x1)
• Suitable (durable) backpack (x1)

Tools that I used:
• Solder iron
• Drill
• Wire strippers/cutters
• Assorted drill bits
• Screwdrivers (for mounting into enclosure)

Step 3:

The TDA1558 puts out about 22 watts into 2 channels. It worked for the 6 inch woofer that I used, and it handled a mid range or tweeter as well. I incorporated a simple band-pass filter using one resistor and one capacitor for the low channel. The mid range or tweeter was un-filtered on the remaining channel.

Step 4: Schematic

Picture of Schematic
This is my schematic:
ToXiCATOM9 months ago
so how does it sound?
I'm glad you asked, it actually sounds really well, better than you would originally expect, i will soon find a way to add a video or a link to a video so you can hear it, thank you for bringing that to my attention

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