Tesla Coil Guitar Amplifier

High voltage is not just the name of a song and album from AC/DC.  The latest Another Geek Moment Video from Digi-Key shows how to use a Tesla coil to see and hear "high voltage rock and roll" without an amp or speaker.

This doesn't look safe to build for most DIYers, but I see from videos on YouTube a few people have tried this before.  It sounds a little harsh, with distortion a bit beyond a heavy metal sound, but the Digi-Key setup sounds better than most.  I wonder if you could use a tube amplifier somewhere in the circuit for a smoother sound.... If it didn't sound better, at least it would look even more extreme with the lights off.

Audio Kits and Amplifier Boards

Parts Express has a great selection of DIY parts for audio projects as well as A/V cables and equipment.  They have recently added a DIY kits section to the website.  Most of the products are called kits but I would call most of them boards because come fully assembled and tested.   They stock Velleman and Parts Express brands.  You can find a lot of audio applications including AM/FM radio, MP3 player, and a few Class-D audio amplification boards.  The amplifier boards use Tripath, Texas Instruments and Power Analog Microelectronics chips.   For an example see the video below for the TK2050 Class-D Audio Amplifier Board.  It is one of the higher end kits at $44 US, they start at $9.90 for the 2x2W@4 Ohm Class-D.

Other sources of Class-D Audio amplifier boards:

Class D Audio Inc. Below is a pic of another Texas Instruments Amp.

International Rectifier

Jameco Electronics always has a good selection of audio kits and kits in general.  Here is an example of a guitar effects pedal built using the Perfboard Prototyping Kit.

Electronic Guitar Pickguard

Eli Hughes, a research engineer and consultant, entered the Freescale Make It Challenge for Kinetis MCUs with an active guitar pickgaurd that really works as you can see from the video.

For the technical details on this design see this deep dive video by Eli.  It is pretty interesting how complex this design was for the contest.  He does a great job making the physics and math behind it understandable.

Musical Instrument Amplifier Embeds a PC Inside

Orange Amps' new OPC, a combined PC and Amplifier is designed for Guitar, Keyboard, microphones and more. It includes WIFI and Guitar Effects software and will be available in June 2010. This could have a lot of uses for musicians, you could pair this with a USB MIDI controller for drums, keyboard, or wind instruments. It will be a nice compliment to USB programmable guitar effects. If successful, it will create more demand for PC connectivity in audio electronics.

New Electric Guitar Uses DSP to Emulate an Acoustic

An electric guitar is being developed at the Massachusetts Institute of Technology that simulates a full sized acoustic guitar using a wooden insert and digital signal processing (DSP). The wooden insert is interchangeable to simulate different Acoustics. The newest version is going to use the Freescale DSP56371 with the Symphony SoudBite Development Kit.

MIT News Feature Story EETimes story

Interface Connects Real Guitars to Video Games

The popularity of video games like Guitar Hero and Rock Band should create a lot of demand for systems like Ediface that interface games to musical instruments. Although the MIDI interface can do this, and has been around for years, so far it has not been used in popular games. The best possible solution would be to use an an unmodified instrument like an electric guitar and connect that to the gaming system. Learning to play a real instrument while playing video games would be a great benefit. That is what the Ediface claims to deliver in a small wallet-sized unit. No word on processor or technology being utilized to do the signal processing.

Update: A new PC/MAC game called Guitar Rising is scheduled for release in late 2008 that will use only the computer mic input for an interface to any electric guitar. Not much detail on the web site, but some early prototype demos at game conferences look promising. We will have to see how the mic input compares to a dedicated hardware interface.