How to Make an Altoids Can Amp
Today's portable audio devices are incredibly tiny and convenient. Although the low-powered audio amplifier that is built into such devices can do a fair job of driving the supplied earbuds, the small size and low cost of the components, coupled with the severely restricted power supply, compromises their capability to properly drive a pair of headphones.
Do-it-yourselfer audiophiles have designed several small battery-powered amps to solve this problem, and one of the most popular is the CMoy design. This design is small enough to build into an Altoids can and efficient enough to be powered by three AAA cells. The availability of completed boards has made it easy for even the neophyte to make an Altoids can headphone amp.
Things You'll Need
- Awl
- Small toggle switch
- 1/8-inch stereo audio jacks, 2
- Soldering iron
- Solder
- 4-inch-long pieces of insulated hook-up wire, 7
- Battery holder with leads
- CMoy design amp board, prewired or scratch built
- Scissors
- Cardboard
- Hot glue gun
Instructions
-
-
1
Punch three holes in one end of the Altoids tin using the awl. Remove the mounting nut and washer from the switch and the two headphone jacks. Push the switch through the center hole from the inside, and reinstall the washer and nut from the outside to hold it in place. Install the headphone jacks in the outer holes in the same manner.
-
2
Solder a piece of hookup wire to each of the three terminals on each of the two headphone jacks. Solder the last piece of hookup wire to one of the terminals of the switch. Solder the red lead from the battery holder to the other switch terminal.
-
-
3
Solder the three wires from one of the headphone jacks to the corresponding input pads on the amplifier board, observing correct polarity. Trial fit the board first, and shorten the wires as much as possible.
-
4
Solder the three wires from the other headphone jack to the corresponding output pads on the board, observing correct polarity. Again, shorten the wires as much as possible prior to soldering.
-
5
Solder the black lead from the battery holder to the ground connection on the board. Then solder the wire from the switch to the B+ pad on the board, after shortening the wire to fit.
-
6
Cut a piece of cardboard to the same size as the amplifier board, using the scissors. Glue the piece of cardboard to the bottom of the board, using the hot glue gun. Then glue the board into the Altoids tin, near the switch and headphone jacks. Glue the battery holder into the other end of the tin.
-
7
Install batteries, plug the headphones into the output jack and plug the jumper cable into the input jack of the amp and the output jack of the audio device. Switch the amp on, start the audio device and set its volume at mid level. Adjust the board-mounted amp gain control to the maximum comfortable listening level. When listening, adjust the volume via the control on the device.
-
1
References
Resources
- Photo Credit mp3 image by Magalice from Fotolia.com
