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Acoustic instrument with added speaker in the Body? Answered

Hi... :-)

I am in a mariachi band and play an acoustic instrument called a guitarron. Sometimes at gigs it is too noisy or too large a venue that it is difficult to hear the acoustic instruments and singer w/out mics and would like to try and make my guitarron into a portable speaker system which has ample space to add hardware.

I am looking forward to reading all the fantastic, innovative ideas (even the sarcastic with, if any), but would like to:
 *Keep the weight at a minimal level (as I will be carrying my instrument)
 *Allow inputs for a mic and 1/4" jack (1/4" my guitarron has thanks to an "instructables user", which works great!)
 *Allow for mp3 input
 *Battery powered, if possible
Also the speaker will have to be small to fit through the sound hole, but if needed for better, louder sound I can make an opening to the body to allow for a larger speaker.

And if anyone has any other suggestions or a similar idea to what I want to achieve, please post it...
Thanks to all who have taken the time to read my project idea!!! Hopefully it is possible and not too far-fetched...


Here's what I like

Here's what I like


3 years ago

It's not too far-fetched, there have been other guitars with amps/speakers mounted inside.

The biggest concern with an acoustic instrument is that it will feedback like crazy, which is a common issue with all hollow-body guitars, even with standard (external) amplification. Even miking with a PA can lead to this problem. Hollow instruments are just very resonant. It is the reason solid body guitars were invented, in fact.

If you are willing to modify the instrument (it sounds as though you are), then you can reinforce parts of the guitar to prevent unwanted resonance, moving towards a "semi hollow body" type of instrument.

I don't know why I didn't think to start a google search for instruments with amps/speakers mounted inside. That was dumb on my part... I just thought it was something unique I was trying to create. Thanks for that!!!

I found this site http://www.gizmag.com/unlimited-smartphone-electri... and it is exactly what I am trying to create. But how to or where do I start? Any thoughts?

Thanks for taking the time to comment on my project!!!

Teisco made one in the mid-1960's, and there have been others since.

That's an interesting little plastic guitar (your link). There's a picture on the page that shows the construction of the top half, and the body isn't solid plastic (too expensive), but it's not a resonant structure, either. Any guitar that doesn't "self amplify" via it's inherent structure (any non-acoustic one) --well, there's no limit, as far as materials or construction.

Re feedback: an all-in-one guitar (pickups, amp, speaker included) would require two transducers--one to pickup the sound, another to reproduce it. Since both are mounted in the instrument, it's essentially a "positive feedback loop." The pickup picks up the sound of the speaker, feeding that back through the amplifer to the speaker, back to the pickup, etc., etc., ad infinitum. When it comes to audio "positive feedback" is usually not a good thing...

Still, the problems can be overcome, or there wouldn't be any historical examples...

You also might look at "sustainers" for electric guitar. There are several DIY projects that do this -- it's uses dual transducers to feed back signal into the strings in a controllable way. You might learn what not to do for your project, since they fight a similar battle to produce the desired results. Fernandes makes a commercial version of this.

Don't get me wrong as I am not a musician but do you want to be able to use the instrument properly after the mod or just use it as a case for a speaker but never again play on it?

If you want to keep it as an instrument forget about a putting a speaker in as it will ruin the accoustics of the instrument.

You can use standard guitar pick ups to get the sound to a little amplifier, add a mixer and connect the other instruments as well.

In case of enough space I would prefer a dual mono system - all instruments and singer from the left into the left amp and the other way around.

You can also get quite sensitive piezo "microphones" that can be glued onto the body of a guitar or similar to be used as an input for an amplifier.

But you have to find the right spot on the instrument to get the sound to match.

I would like to continue playing my instrument; and if not as an acoustic bass anymore then maybe as an electric bass might work.
I have the piezo mic installed ( if you saw the pics of my instrument : the 1/4" jack and the wires are visible ) and it works well, so maybe if I can convert my acoustic into an electric then add the dual mono system inside I can make it work. (I don't know what a dual mono system is, so I'll look it up.)
I have an older version of my instrument, so if adding the speaker system on that one doesn't work like I envisioned, then I can just use it as a case for a speaker like you've said. I've also looked at YouTube videos, but have not seen anything to what I am trying to make, so it will be unique...

Thanks for your reply! And if you can share more insight as to how I can make the mod the would be fantastic!

Your biggest problem will be be to eliminate the acoustic part so it won't interfere with the microphone.

At least I think you don't want to hear two different sounds when playing in a smaller room...

I think the single pickup systems that go at the base of the strings are better suited for your project as they eliminate the vibrations from the body of the instrument, however this will also change the sound - similar difference from an acoustic guitar to an electric one..

You might need a small amp and some time to experiment with the right pick up system and how to make your instrument "silent" like an electric one.