I end up spending a lot of time in the garage or the driveway, and sometimes it’s nice to have soothing music in the background – and other times it’s nice to have adrenaline-pumping rock assaulting my ears. I used to have a moderate-sized old boombox for that purpose, but my son took it camping… then threw it out when the batteries died (as if I could make this up!). Parts Express had a good sale going on a little while back, I was about to commit to buying a little amp with an integrated USB port, and was searching eBay for some Bose or Cambridge Soundworks Sat/Sub combos – because anything that is “just” 2 channels is pretty much a giveaway these days. I was getting ready to pull the trigger and buy, when I thought to myself, “Nah – let’s see how close to free we can do this.” So, off to the parts bin.
I suppose it helps to have pack-rat inclinations, I save a lot of old stuff that I should probably throw away.
Speakers: I ran across a set of 6×9″ Polk “triaxial” speakers (in, of all things, an Infinity 10.1d sub box) in the basement recently. These have probably been sitting in my basement for 12+ years, I had briefly installed them in a 1994 Accord. I kept them when I sold the car because they sounded great and I was sure I’d put them in some family member’s car. In spite of the seriously-compromised design of a 6×9 cone with 2 drivers mounted in front of it, they will do the job nicely for my garage. While I was going to stay cheap and build enclosures out of plywood scraps, I splurged and bought a set of Scoshe 6×9″ enclosures on Amazon. Considering that $24.99 was the total outlay for this project, money well-spent.
Sound source: If you’ve worked on multiple project cars, chances are you’ve come across a head unit or two you didn’t need. My latest project car had a Sony headunit with a USB input, bluetooth, bells and whistles galore. Not good enough for the “no compromises” MR2 Spyder project, but just fine for the garage. I hooked it up to my bech power supply and one of the polk-in-scoshe speakers to test; works good, sounds good.
Power: Of course, there’s no 12v power source in the garage to run a car headunit. So we need a power supply. The purist in me kicked in, I started searching for linear 12v regulated power supplies. Hmmm. Tons of inexpensive power supplies out there, but anything with some iron in it is still expensive (see “purist” and “linear” earlier in this paragraph). Aha – I remembered I had an old regulated power supply somewhere in a box, my father-in-law used it in the 1970s to power his CB radio (again, I can’t make this up). I even remembered where it was. Took it out, dusted it off, plugged it in and… nothing. Would not run the Sony. A quick check with a voltmeter showed this 40-yr-old 12v power supply was not outputting…. 8.63v. So, let’s open it up and take a look…. really simple design…. cross-reference the one power transistor….. order up some replacement parts and fix it, right? Well…… nah. Let’s not buy parts and spend time. I’ll keep the transformer (see “pack rat,” above) and toss the rest. There are alternatives.
Alternative # 1 – I have a bunch of desktop computer power supplies, let’s look through those. I found 3. Smallest one is 440w output. hmmmm, that’s way overkill (on the bench supply the Sony cranked up high was drawing under 1A @ 13.2v). I just don’t like the idea of running a 440w PS to power a maybe 15w draw. Plus, there’s the heat and the fan… let’s move on.
Alternative #2 – Laptop power supply. A quick search of my bin of AC/DC plug-in converters found a charger brick from an old Panasonic Toughbook: 14v @ 5A. Perfect. Clip the plug end, plug ‘er in and….. we have tunes. Well worth the $25, and I made some space in the parts bins to boot!
