Acoustic/electric controls

[mairj40]

I have an old acoustic electric that I am working on. It originally had two knobs (one volume and one tone) sticking out of the body by the neck. I would like to install a more modern type of preamp setup on it. How difficult would it be to install a newer system?

[SwedishLuthier]

That, of cause, depends on what type of system we are talking about and what you want to do with the "scars" from the old system. I'm assuming the current controls are mounted at the sides of the body and that it is ok for you to either plug the current holed with something that is visible or just leave the controls in place. If not you also need to adress the holes in some way or another. You can even make the holes a feature and call them sound ports...

Anyway, if you are looking at a system that is mounted like this

it takes some skills to do it. You need to assure that you doesn't weaken the structure too much (at least don't cut through too many side braces). The preamp need to at least reasonable match the curvature of the sides to fit nicely. And you need to be able to cut a few straight lines in the side. If you feel comfortable doing this it shouldn't be impossible to do it yourself

[WillyD]

Could you tell me more about your guitar? Like the make and model, or at least what kind of wood it is made of. Are the back and sides rosewood or mahogany? I ask because if the guitar is made of rare and expensive woods I would hesitate before recommending a new system that involved cutting into the sides. I have seen preamp systems that mount the tone and volume controls inside the sound hole where they can be reached with a finger but are not noticeable.

You still have to deal with the holes left from the old control nobs. I would not leave them open. Instead try to find some kind of plug. To move forward on that part of the project you have to answer the question: "do I need the plug to be as invisible as possible, or am I OK with it being off color."

If invisibility is important to you, then find a piece of wood that matches the wood on the sides of the guitar and is the same thickness ( check lmii.com or your local guitar repair shop ). Cut patches to fit from this wood and glue them in place using a cleat on the inside of the guitar. If possible the cleat should be made of the same material as the patch only thicker, about 1/8" or so. Clamping a patch and cleat in this area of a guitar is very tricky. I would say you'll have to use two rare earth magnets to exert pressure. They can be purchased online at stewmac.com. To make the seams look good you can pile up a small mound of dust from sanding the patch wood around the seam of the patch. Then put drops of CA glue all around the pile of sanding dust and let it dry. Then sand the area flush with the sides. What grit of sandpaper you start with depends on how uneven things are, but I would not start any rougher than about 800 and work your way up to 2000 grit. Then you are ready to apply a new finish to that area of the wood. I don't know much about refinishing guitars so you might want to take a look at other tutorials for details on that part.

If you don't care much about the patch matching the existing wood, then I suggest looking around hardware stores and places like that for small plastic "buttons" commonly used to cover screw caps in furniture and the like. I most often see them in black but you might get lucky and find some in wood grain.

Cheers

WDA

[Prostheta]

I think that given your recent excursion into the insides of your repair guitar, you should manage this quite nicely. I examined how the pre-amp to one of my Washburns was mounted a while back and as Peter says, it is just about placement and maintaining structural integrity. If the sides on that particular guitar are less than ideal, it is not impossible to glue in a patch of flexible veneer to shore it up. My Washburn was straight cut through with the screwholes being the areas that would need the most attention to getting right.

Peter - what's the best way of organising loose wiring inside the box? Adhesive cable retainers on the sidewalls?