Last week I received the K40 Chinese laster cutter I ordered from eBay. So I am building a 2x 2 Watt Bluetooth Sound Box. I mean, what else can you do? There are plenty of instructables available, like this one for example. Beautiful.
The Bluetooth Sound Box is constructed from the following components; a Bluetooth receiver, a 2x 2 Watt amplifier, and two 4 Ohm 2 Watt speakers. For fun, I added some LED. Just to give the final version a bit of retro look.
As a first step I connected the components, just to make sure the electronics works. Straight forward really, just connect to the amplifier board. Which is – size wise – somewhere in-between tiny and small, so you might want to use glasses.
After verifying the electronics work, or at least that I managed to connect the components in the right order even if I did not stick to the proper colour code (plus is Red, right?), I cut my first box. Very simple. Just straight. The tricky part here was the creation of the TLP file. What is a TLP file? it is the file format that Moshidraw LEFT (almost good enough piece of software, just don’t touch the USB wires otherwise it goes haywire and somehow cannot calculate cutting patterns anymore…..?). PLT fils is not one of the standard exports on your average Illustrator application. After some search, I found that Ink can one the one side import Illustrator (.ai) files and export into .plt files. Great! After adjusting the mirrors a bit, the K40 actually cuts, and in the right scale etc. Careful, though. The laser is (according to the specifications) 40 Watt which is enough to cut through your skin. Even if it is not 40 Watts, it is strong enough to cut through your skin. No need to try it. Trust me.
Again just checking it all works. And it did. It did. Sound was crap, though. There seems to be an art to building speakers that goes beyond connecting components and putting them in a box. In any case, not discouraged by the crappy sound, I proceeded and created a slightly better looking sound box, from plywood, and as an extra twist, adding the LED light to give it a bit of retro look. Still waiting for the power supplies to arrive, for now I powered it via the Mac’s USB port.
Happy, proud, etc. Note the how the screws connect the front panel. Simple stuff. Sound still is crappy, though.
For a next update, I made two changes. First, the panel inside on which the speakers are mounted I fixed on all six corners. See the six screws on the front panel. This actually made the sound almost decent. More than decent. Still 2 Watts, but almost decent. As a next step I will try a slightly more powerful amplifier, maybe make the box a bit larger etc. Also, maybe talk to an expert. Second, and after some feedback from friends, I changed the front panel pattern. The feedback was that this should be more organic and random. So, playing around with Wolfram’s Mathematic and the Golden Ratio resulted in this – fairly standard but still nice – pattern.