Tag: DIY

Box Amplifier Kit – Part 1

DIY Box Amplifier Kit

The do-it-yourself (DIY) project I chose to work on this past weekend was waiting for me in a box for over two months. I ordered the Box Amplifier Kit from the Maker SHED store around the end of September. Things, as usual, got busy and I just never made the time to assemble it.

Box Amp Kit

What originally interested me in this kit was a need for a small, portable, amplified speaker that I could use with my iPod, electric guitar or anything else that had an audio/headphone output. This kit does that. The description from Maker SHED store follows:

A great-sounding, loud amplifier kit designed to easily fit in almost any box (cardboard or otherwise). It goes from solder station to stage in under 60µF!! Solder it up, cut out holes for the speaker and controls, and plug in your instrument!


* 1/4″ Jack connects to most instruments (electric guitars, keyboards, theremins, etc)

* Highly portable – take the amp to your jam session, band practice, or the front porch!

* Simple installation in a box allows for easy enclosure customization

* Solders up quickly and easily

* Great for beginner “makers” and accomplished musicians alike

* Works with any center positive 9-volt power supply

* Can be modified to operate on a 9-volt battery

via Box Amplifier Kit.

What’s even better about this kit is, for a relatively low price ($29.95) and a little effort with a soldering iron, I get the satisfaction of having made it myself.

My assembly process.

Sunday afternoon, I finally unpacked all the parts, spread them out and got to work. Using the easy-to-follow How to Instructions I was able to assemble my amplifier in less than an hour. See some pictures of my assembly process below. In addition to the standard DC power jack that is for connecting to a “wall-wart” AC adapter, I added a 9-volt battery snap for portable use. After hooking up the power, I plugged in my electric guitar. Strumming a few notes, I smiled when I heard how much sound came out of that little speaker. Next, I connected the headphone output of my iPod to the amplifier. Again, even though monophonic, it sounded pleasantly full.

In search of …the perfect box.

The reason it’s called a box amplifier is simply because you have to find your own box to mount the amplifier and speaker in. Like the product description says, the assembled kit is intended to fit in almost any kind of box. But it needs to be housed in some kind of box for both protection and to provide the best sound. The kit came in the small cardboard box you see in my pictures with the big red “AMP” stamped on it. I think the stamp looks cool and I considered using that box, but after trying various placements of the speaker and circuit board inside, I decided against mounting it there. It was just a bit too small.

In Part 2 of this project, I’ll describe finding the perfect home for my new box amplifier. My goal is to use “found” materials for the enclosure. Nothing bought or manufactured. Something that can be reclaimed and re-purposed. In short, I’m in search of …the perfect box.

Giving the PalmPre a MintyBoost

I’ve spent about a week and half with my new Palm Pre and I’m still enjoying using this phone. This happens to be the week the new iPhone 3GS is being released with all the fanfare you’d expect from an Apple product release. I’m sure it’s a good phone with some nice new features and a lot of people will buy it. That’s cool. I’m not going to compare the two phones – you can find plenty of that information in countless other places. The Palm Pre is what works for me.

Palm Pre (keyboard open)
Palm Pre (keyboard open)

What I’m excited about today is the the MintyBoost Kit I ordered from Adafruit Industries. What’s a MintyBoost Kit? It’s a make-it-yourself portable battery pack and USB charger in a mint tin. Once assembled, the MintyBoost will charge my Pre and many other rechargeable USB devices. I learned about this little $20 device on the PreThinking Blog.

MintyBoost battery pack & USB recharger
MintyBoost battery pack & USB recharger

My MintyBoost Kit shipped today and I should be receiving it via USPS Priority Mail within the next couple of days. I’ll get it all put together and post an update on how it’s working for me.