How can I be sure a self-made acoustic won't sound like a cardboard box?

[emmsone]

Hi All, hoping I can get some advice here and tap the vast, vast volume of knowledge and experience here on this forum!

After a successful solidbody bass guitar build at christmas, I got hit by the building bug and decided I would build an acoustic next. I'm pretty confident that my building skills mean I can make what needs to be made, but just following build instructions well and having a nice looking and well built guitar means sod-all if it sounds like a wet fish being slapped on a rock.

This question has been annoying me for months (since i finished the bass) and as much as i've read about sounds and voicing, just about all i've worked out is, "until you put the strings on you just don't know" (unless i can find some frequency analysis equipment for free lying around behind a university or something to that effect)

As much as i'd like to be able to just have a bash and hope for the best, i just can't outlay the cash for a side bending device and all the woods needed and the rest without knowing i might at least get SOMETHING useful.

How am I supposed to get around this? obviously the sound/voicing it all comes with experience, but if you have none, where do you start?

With the bass guitar I built, as long as it was set up ok and played ok, the sound all came from the pickup, so you find in advance what sound you want from your favourite pickup and as long as you build it right, you know pretty much what you are going to finish with. Unfortunately an acoustic is nothing like this.

Any advice you can give is much appreciated.
Dave

[Sperry]

Leave nothing to chance.

[Ben-Had]

When I first got started I took a building course. The cost of the course and guitar cost me less than a Martin D-18 (which was my model guitar) and sounds just as good (if not better). That way I ensured I'd good good woods, learn the procedures I'd need to continue, learned the basic tools I'd need to build more. Since then I have built close to 70 guitars and have a nice little retirement business in repair and custom building.

[MC5C]

If you are starting out cooking, you follow a recipe. You follow it exactly and if it was any good, you'll have an acceptable result. Same with guitar making. You get the book or set of plans of your choice, and you do exactly what they tell you to do. The biggest thing with building an acoustic guitar, aside from the obvious woodworking skills, is bracing and tuning the top. You don't know how to do that, so you build your first top exactly they way the instructions say to - but paying attention the whole way to what the wood sounds like when you tap it, what it feels like when you flex it - and then some of the words about voicing a top will start to make a little sense to you. You listen to the wood and try to make it musical even before it's glued into a box.

Then you glue up the box and start to worry about not screwing up the finishing...

[dekutree64]

Originally Posted by MC5C

The biggest thing with building an acoustic guitar, aside from the obvious woodworking skills, is bracing and tuning the top. You don't know how to do that, so you build your first top exactly they way the instructions say to - but paying attention the whole way to what the wood sounds like when you tap it, what it feels like when you flex it - and then some of the words about voicing a top will start to make a little sense to you. You listen to the wood and try to make it musical even before it's glued into a box.

Yep. If you can find a local luthier to help when you get to the soundboard thickness and then brace carving, that could be the answer you seek. Make sure you flex the unbraced soundboard along the grain and commit the feeling to memory, and tap on the final carved braced plate and remember how long it rings and low pitched it sounds compared to when the braces are first glued on and it just makes a short ping.

Don't get caught up in trying to make it the most spectacular, highly responsive guitar ever. The more lively (lower mass and stiffness) you make the soundboard, the more any frequency response issues stand out and make it sound funky. Learning to build that style takes time and/or a few failures. But luckily steel strings have enough raw power that they sound good even on moderately responsive guitars, like your typical Martin.

A side bender can be made quite cheaply using a piece of exhaust pipe from a muffler shop scrap bin, and an electric charcoal starter squashed in a vise so it fits in the pipe. Mine is 3" diameter, but even better would be a 2.5" pipe squashed into an oval shape so you have more radii available.

[emmsone]

Originally Posted by Ben-Had

When I first got started I took a building course. The cost of the course and guitar cost me less than a Martin D-18 (which was my model guitar) and sounds just as good (if not better). That way I ensured I'd good good woods, learn the procedures I'd need to continue, learned the basic tools I'd need to build more.

I was considering going this route but the 2 places that do build courses here in Switzerland are a) very very expensive and b) from what i've seen in my research of these places, they use kit builds with pre-bent sides, pre shaped necks and everything. I'm not sure i'd learn enough from these courses to be worth it. Seems the opposite of what I need. I had looked at a few courses over in the US, but by the time I add on flight and accommodation costs, that doubles the already expensive course price. That is a long way from ideal.

Originally Posted by MC5C

If you are starting out cooking, you follow a recipe. You follow it exactly and if it was any good, you'll have an acceptable result. Same with guitar making. You get the book or set of plans of your choice, and you do exactly what they tell you to do. The biggest thing with building an acoustic guitar, aside from the obvious woodworking skills, is bracing and tuning the top. You don't know how to do that, so you build your first top exactly they way the instructions say to - but paying attention the whole way to what the wood sounds like when you tap it, what it feels like when you flex it - and then some of the words about voicing a top will start to make a little sense to you. You listen to the wood and try to make it musical even before it's glued into a box.
Then you glue up the box and start to worry about not screwing up the finishing...

This is basically my question, if I follow the instructions of a build and get an acceptable result great, but with cooking you can follow instructions exactly and it doesn't give you the same result because you have different equipment to the recipe writer and the recipe wasn't written after their 1st attempt, unfortunately with building a guitar, its a lot more expensive to just bin it and start again if it doesn't sound good.

Originally Posted by dekutree64

Yep. If you can find a local luthier to help when you get to the soundboard thickness and then brace carving, that could be the answer you seek. Make sure you flex the unbraced soundboard along the grain and commit the feeling to memory, and tap on the final carved braced plate and remember how long it rings and low pitched it sounds compared to when the braces are first glued on and it just makes a short ping.

Don't get caught up in trying to make it the most spectacular, highly responsive guitar ever. The more lively (lower mass and stiffness) you make the soundboard, the more any frequency response issues stand out and make it sound funky. Learning to build that style takes time and/or a few failures. But luckily steel strings have enough raw power that they sound good even on moderately responsive guitars, like your typical Martin.

A side bender can be made quite cheaply using a piece of exhaust pipe from a muffler shop scrap bin, and an electric charcoal starter squashed in a vise so it fits in the pipe. Mine is 3" diameter, but even better would be a 2.5" pipe squashed into an oval shape so you have more radii available.

I wouldn't expect the first effort to be highly responsive or perfect, but i just want it to be decent and not sound like a toy or a cheap 100 dollar yamaha and I'm still trying work out how to guarantee it won't be that terrible!

I've seen youtube videos and posts on here about those homemade heated pipe side benders, but living in a single room apartment its not safe to do that here, and the woodwork shop i can get access to is public access, so they probably wouldn't let me do that in there either. i was looking at the chinese ebay electric ones, probably just about affordable.

[Rodger Knox]

Think about it this way. All the major factories build to dimensional specifications, which is exactly what you will do by following a plan. There's no reason to believe that what you build won't sound just as good as the factory guitar, provided you use good materials (more on that later) and accomplish the woodworking. You've built a bass, so you have some idea of the woodworking required. An acoustic is more difficult, but most first builds that I've seen were at least as good as factory guitars acoustically, but the fit and finish frequently is not all that good.

It's actually more difficult to refine your woodworking and finishing skills to come close to the fit and finish of factory guitars. Starting with good materials is important, but that doesn't mean it has to be expensive materials.

I'd recommend getting your top from :http://www.alaskawoods.com// . They're great to deal with, and all they sell is salvaged old growth. The more expensive is better cosmetically, but the cheaper grades may have more "character" and are just as good acoustically. The rest of the wood isn't that important acoustically, so get something that's inexpensive and easy to work. Check out http://www.rctonewoods.com/RCT_Store/, they have quite a few options for less than $100 for back and sides.

Don't try to get too fancy, plain wood binding with no top, back, or side purfling. Binding is difficult enough for a first build, but you do need to do binding on an acoustic. That is a bit of woodworking you probably did not do for the bass.

[dekutree64]

It's fairly easy to match the quality of the better factory makers. It probably won't sound like a cardboard box as long as you use a softwood soundboard and reasonably thin finish. Hardwood soundboards can be great too of course, but they're easier to mess up.

As others have said, pick a recipe and follow it. Once you get to the braced soundboard stage, if it sounds tight, you can generally carve them lower than the plan. But remove a little material from everywhere, rather than a lot of material from certain spots. Keep the overall stiffness distribution the same, but just lower the absolute value of it.

You can also do some voicing by sanding around the perimeter of the soundboard after the box is closed. Much better tap tone at that stage than with a free plate. You can even glue the bridge and string it up before doing that, to really hear what effect each change has. But then you have to either unglue the bridge, or finish around it. But finishing around it isn't too much trouble unless you're trying to make a perfectly flat mirror gloss.

[LouieAtienza]

Well, for one, don't use cardboard! (Though Robbie O'Brien may say otherwise...) But seriously, if you are seeking a particular sound from an instrument you want to emulate, it would help to use similar materials.

I don't think you necessarily need to do frequency analysis to build a good instrument.

As to tooling, you may want to see if there is a maker-space in your area, and join it.

Bottom line - don't worry about something you won't know about! There are many free plans online. It's not hard to "tune" a guitar in the white, strung up. Though as others already mentioned, starting off with decent materials goes a long way - and makes it easier, because it's easier to work straight grained quartered wood!

[Tom West]

Follow this plan.
http://www.stewmac.com/How-To/Bluepr...itar_Plan.html
Tom

[capohk]

I recently bought some plans from these guys - great, detailed plans with all the templates you need (no affiliation). I would strongly recommend not using figured wood for backs and sides for your first guitar. I found that plain black walnut bends easily and sounds great. Mahogany is also a great choice I think.

I agree with the problem of uncertainty regarding bracing and final 'tone'. I haven't built enough yet to say that my methods are good, but I have been pleased with the guitars I have made so far.

I have read and read about the ideas behind trying to be scientific or somehow magical about tap-tuning. At this point, I cannot see how being good at second guessing the finished tone of a guitar by assessing a braced plate can be something that you can do consistently other than with the 'muscle-memory' of having built tens or hundreds of guitars. There are simply too many variables to account for to be able to apply some kind of scientific theory in the absence of experience.

My first reading on building guitars was the most useful - William Cumpiano's book. Below is a quote from an interview with him that I feel strongly must be at least mostly correct:

Any words of wisdom or secrets to pass along to the full-time or hobbyist luthier?

Be very, very skeptical of any and all claims of foolproof, controllable acoustic “adjustment” of guitar tone by scratching little bits of wood in diverse magical, discrete areas of the guitar, whether its called “tap tuning,” “tone adjustment,” “top tuning,” or by any other seductive name. There’s nothing useful there to learn, no matter how “scientific” or enticing or romantic it might seem.
The secret of consistent excellence in guitarmaking lies among the following, if anywhere:
• Architectural optimization: minimum adequate structure: like Ervin Somogyi once said, “guitars sound best when they are built just beyond the cusp of collapse
• Precision and control of the guitar’s three-dimensional geometry
• All tonewoods selected for even, uniform, texture and fiber organization
• Forget the specie. The most expensive, exotic, and rare hardwoods add not a whit of tonal advantage over inexpensive and plentiful alternatives. Experiment with local materials. One of the great, unknown domestic hardwoods of the future is Sycamore.
• Soundboards should be selected for predominance and proliferation of medullary rays (“silk”) over all other factors. This feature denotes the material at the peak of its architectural efficiency (stiffness-mass ratio).

[Truckjohn]

The biggest correlation is to err on the side of thinner and lighter rather than heavier and stiffer with the soundboard, bracing, bridge plate, and bridge.

If you look at quiet guitars - they usually are built with heavy tops and stiff bracing.

The next thing is to use the right string size for the size body and construction. Dread and jumbo shapes have to be built heavier and stiffer so they don't sound woofy and flabby. Because of this - they usually take heavier strings to really drive them. They can be almost deafening up close when played hard with heavier strings, though.....

Small guitars on the other hand are very hard to build so light so that they sound woofy and flabby... Their tops are lighter and stiffer just by the sheer virtue of size/geometry and can be surprisingly loud even with light strings. Just the simple fact of dimensions - a 14" lower bout guitar top weighs 75% of a 16" lower bout guitar top at the same thickness but is about 15% stiffer all else being equal.

Thanks

[emmsone]

I'm finding it interesting how you guys are pretty much all saying that all I have to is follow some decent plans and i'll get an decent guitar.

That's good news.

I'll probably have to buy some plans to put up against the ones i've drawn up myself in CAD and see where i need to update my own plans to get a decent final result.

[redir]

Plans tend to be over braced so take that into consideration. What you need is a base line. Start building today make your mistakes and move on. Your tenth guitar will be a good one.

Your first one will probably be good enough and in fact better then most of the store shelves as long as you get the action, intonation and playability right. When it comes to fit and finish that is a whole other art form so don't worry about it too much at this point. If you follow a plan, maybe even reduce it a bit, and get the setup right you will have a descent enough guitar.

[Alan Carruth]

Think of it this way:
People have been making guitars for a long time, and some of those folks were pretty smart. Everybody is always trying to make a better one; changing stuff around and hoping for the best. Every once in a while one of the experiments succeeds. When that happens all the other makers copy that new feature so they won't be left behind, and it becomes part of the 'standard'. Thus the standard designs are really pretty well optimized, and are very hard to improve on. If you use good wood, do good work, and stick to a standard design, it's hard to go far wrong.

'Good' wood is one key variable that's hard for the beginner pick out sometimes. Most of the grading standards on wood are cosmetic rather than acoustic. It's not hard to find 'AAA' or 'Master' grade tops that are really not very good from a structural or acoustic standpoint, but just look great. Nor is it difficult to find cosmetically challenged tops that will make an excellent sounding instrument. Basically, in the top, you're looking for light and stiff, but it can take a while to develop a sense for that. There are ways of measuring these things, but they take time, and the suppliers don't usually bother. For your first few efforts (nobody makes just one...) I'd say don't bother with getting a high grade top; just go with something in the middle range. I'd also stick with Sitka, if only because it's common enough that you might get a better top at a given price than you would with some more fashionable but scarcer wood.

B&S woods also vary, of course, but since most of the sound is in the top I would not worry too much about that in terms of tone. Unless you really have a thing for the mahogany sound, I'd say go with Indian rosewood, in a middle grade. It's easy enough to get in good quality for a reasonable price, makes as nice a guitar as you're likely to manage the first time out, and usually doesn't give any trouble in bending or whatever.

Keep in mind that a guitar is a system. There are a number of ways to make one that all work, even though they're different. If you get a book or a video series as a guide, get one, and do what they tell you to. If you get three or four books, choose one and do that, and put the others on the shelf. Trying to follow more than one will just be confusing. Later, when you've made a few, you'll have the experience to see how the different systems compare, and be able to choose features of another system to include in your own building.