MIDI is a great tool for virtually any musician. Unless you’re a keyboard player, though, it might be hard to use it live. [Evan] recently came up with a great solution for all of the wistful guitar players out there who have been dreaming of having a MIDI interface as useful as their pianist brethren, though. He created a touchless MIDI controller that interfaces directly with a guitar.
Brothers [Armand] and [Victor] took their acoustic guitar to the next level, making their own pickups to turn it into an electric guitar. The result is that awesome electric guitar sound.
The pickups are homemade magnetic pickups. Each string has a steel bolt behind it with three ceramic magnets on each bolt. A coil is also wrapped around all the pickups. That coil is what’s connected to the wires going to the amplifier. When a string vibrates, it changes the magnetic field in the pickup which induces a current in the coil and that is then sent on to the amplifier to be altered as desired and turned back into sound. Of course that meant the guys had to replace their nylon strings for steel ones.
With just the volume amplified the sound isn’t very different but when the amplifier’s gain is turned up and the volume turned down the sound is undoubtedly electric. As you can hear in the video below, Johnny B. Goode, Paint it Black and Satisfaction take their acoustic guitar’s sound to a whole new level.
Cutting the slots in a guitar’s neck for the frets requires special tooling, and [Gord]’s contribution to his friend’s recent dive into lutherie was this lovingly engineered and crafted fret mitering jig. We’d love to have a friend like [Gord].
We’ve covered a number of [Gord]’s builds before, and craftsmanship is the first thing that comes to mind whether the project is a man-cave clock or artisanal soaps. For this build, he stepped up the quality a notch – after all, if you’re going to build something you could buy for less than $200, you might as well make it a thing to behold.
There’s plenty to feast the eyes on here – an oak bed with custom logo, the aluminum jig body with brass accents, and the precision bearings that guide the pricey backsaw. Functionality abounds too – everything is adjustable, from the depth of cut to the width of the saw blade. There’s even a place to store the adjustment tool.
The result? Well, let’s just say that [Gord] and his friend [Fabrizio] are kindred spirits in the craftsmanship department. And [Fab]’s not a bad axeman either, as the video below shows.
Sheet metal. Beer cans. Pieces of chain. Not items you’ll typically find on the BOM for a custom guitar. But nobody told [Maarten van Halderen] that, and so he threw them all together into a gitaar van schroot, or scrap guitar for the Dutch impaired (YouTube link).
The video shows the build process, starting with plasma cutting and welding sheet steel for the body. The neck is fabricated from rectangular steel tube, with nails serving as frets. Overall it looks like a Les Paul, except for the sink strainer basket mounted in the sound hole and the crushed beer and soda cans tacked to the body for decoration. The chains are a nice touch too. And this doesn’t appear to be [Maarten]’s first attempt at scrapyard lutherie – toward the end of the video we see that the beer can axe joins a very steam-punk looking older brother. They’re both good-looking builds, and the video after the break proves they can sound pretty good too.
The folks at [ElectroSmash] recently released 1Wamp – a one watt, open hardware, Guitar amplifier packed with features. It consists of a JFET based pre-amplifier, a Big Muff Pi a.k.a BMP based Tone control and an LM386 power amplifier. The dual JFET pre-amp provides tube-like sound, the BMP provides a nice tonal range while the LM386 can drive various types of output’s ranging from headphones to speaker cabinets.
1Wamp had controls for Tone, Volume and Gain, a Speaker/Cabinet output, a headphone output with an integrated attenuator switch and an aux. input. The aux. input is handy as it adds any line level input signal to the guitar sound, allowing you to practice with metronome or MP3 backing tracks or drum bases. It runs off either a 9V battery or can be powered via an external power source. [ElectroSmash] have released all the native KiCad design files. If you’d like a quick look at the design, check out the Schematic PDF and the Bill of Materials. There’s also a handy assembly manual [PDF] that shows how to build it in five easy steps.
Their blog post provides extremely detailed circuit analysis of every part of the design, starting from the power supply filter to remove mains “hum” all the way through to PCB layout considerations for noise reduction. Oscilloscope screen shots provide signal analysis showing bias points and signal levels throughout the circuit. The choice of value for every component is explained, along with the consequences of changing those values. This makes it easy to customise the 1Wamp to suit individual tastes. We also noticed SPICE models for the recommended and alternative JFET transistors, in case you need to customise the design by changing component values.
There’s also a lot of audio amplifier trivia, references and links shared in their post. This includes a detailed analysis of the LM386 op-amp. Want to add some bling to your 1Wamp build? There are a lot of handy tips on how to add cool LED lighting to the amplifier if it is mounted in a standard metal enclosure. However, the PCB has some really nice graphics, so an acrylic-sandwich-type enclosures look best. Check out the video that walks through the features of the 1Wamp and shows off its performance. And while on the subject of Audio electronics, here’s one of their earlier projects – an open source Arduino guitar pedal.
Documentation to this level proves several things, most notably a love for this design and deep consideration for those who will use and modify this amplifier. It’s a great pattern to follow with your own Open Source designs.
[fichl] plays electric guitar, and with that hobby comes an incredible amount of knob twisting and dial turning. This comes at a cost; he can’t change the settings on his small amp without taking his hands off the guitar. While larger, more expensive amps have multiple channels and footswitches, this tiny amp does not. Instead of upgrading, [fichl] came up with a device that turns his single channel amp into a completely programmable one, with just an Arduino and a handful of servos.
The amp in question – an Orange Dark Terror head – has just three knobs on the front of the chassis, volume, shape, and gain. [fichl] had the idea of controlling these knobs electronically, and the simplest solution he came up with is cheap hobby servos. These servos are mounted in an aluminum box, and mount to the knobs with a few shaft couplings.
The footswitch is the brains of the setup, with three buttons, four LEDs, and a DIN-5 output jack that delivers power, ground, and three PWM signals to the servo box. With the help of an Arduino Nano, [fichl] can change any of the knobs independently, or switch between twelve programmed settings. It’s an interesting setup, and something that could serve as a prototype for a much larger system on a much larger amp.
Some things just go hand in hand. Hacking and guitars are one perfect example. A huge number of hackers, makers, and engineers have at least dabbled in playing the guitar. Even those who don’t play have heard the swan song of the wayward guitarist “Bro, you fix amps?”. Seriously, once your guitar toting friends find out you tinker in electronics, you’ll never be left wanting for pizza or beer. This week’s Hacklet is about some of the best guitar projects on Hackaday.io!