This will involve installing some mid-range drivers, tweeters, and crossovers into the bodies of two acoustic guitars. Over time I'll update the instructions as I make progress on the project.
So far, I've collected two each of the following:
- guitar,
- mid-range driver,
- tweeter,
- cross-over electronic components,
- speaker terminals, and
- MDF for internal acoustic improvement modifications.
I've also designed a simple cross-over and determined a desired volume for the internal dimensions for the guitar body using a test speaker enclosure (instructions and pictures for these to be added in over time).
I have some quality Vifa mid-range drivers and tweeters that need a new home. I already have a number of bookshelf speakers so have been thinking of making something a little different.
The spec sheet for the driver provides a recommendation for the ideal enclosure volume (3–10L sealed) so I'll be starting with that as a first step. However, I like tight sound and am not too fussed with pushing out a lot of bass (and if later that is desired there's always the option of adding in a port or even a subwoofer to the system) so I'll be looking at making a test housing to pick a desirable sound profile.
The plan is to make a box with a sliding baffle so I can determine the desired volume. I'll put plans for this up over time.
The next step will be to knock up a basic cross-over circuit so the speaker can be tested in the temporary housing and the best volume determined. That will provide the necessary dimensional requirements for the internal volume of the guitar body.
WARNING: ALL INSTRUCTIONS ARE A WORK IN PROGRESS AND ARE LIABLE TO CHANGE ON A REGULAR BASIS TILL THE PROJECT IS COMPLETE!!
Buying vs building
[Discussion of pros and cons]
The main advantage of buying a ready-made guitar is the significant reduction in work needed as compared to building a fake guitar from scratch. The primary disadvantage is that guitar bodies are designed to resonate and to amplify sound, which is not what you want from a speaker housing. I've addressed this latter point in my build by gluing in layers of MDF inside the bodies of the guitars.
Buying
This option involves buying a guitar and then making alterations to it to make it suitable as a speaker housing. (I'll provide more details about this later in the instructions.)
The main considerations to make when buying are guitar are as follows:
attractive shape and colour;
choosing one with that has an internal volume a little larger than required for the mid-range driver being used; and
location of internal framing, as cross-beams that are placed under the sound board can make the widening of the centre hole for placement of the driver quite difficult.
This was the option I went with for this project, as I wasn't overly keen to build any from scratch right at this time. Perhaps in the future...?
I was able to find some ludicrously cheap guitars online that looked okay but importantly were the right volume [see step XX below].
Building
Quality speaker housings are typically constructed from MDF (either painted or covered in a timber veneer) in order to provide a solid, dampened structure. The ideal approach, then, when building the fake guitar bodies is to make them from MDF so you have the best of both worlds—a well-made speaker cabinet but one that looks like an acoustic guitar.
2
Selecting a mid-range driver
Finding a mid-range driver is the first step for this project, as this will determine an ideal volume for the guitar body. Alternatively, you can
[I'll add more information in here over time about the selection of drivers.]
3
Selecting tweeters and designing crossovers
[This will briefly cover 1st, 2nd, and 3rd-order crossover choices plus selection of quality electronic components. I will likely heavily reference other sites here because I don't claim competence in this area.
I'll also talk about options for tweeters in line with the previously chosen mid-range drivers.
Inductors, polyester NP capacitors, polyspeaker protectors, tweeter, and mid-range driver.]