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I scratchbuilt a guitar (shrunken Dreadnought shape). I am delighted with its depth of resonance and long sustain. My instructor was playing it yesterday and mentioned that it sounded bass-heavy. Um. If I wanted to experiment at balancing the base more evenly with the treble, would using lighter strings, for the sake of experimentation, on the E,A,and D strings bias the sound to more of a balance?

Thanks for any comments, and insight, and (much needed) instruction.

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Peter Havriluk

There was a big discussion related to this recently, on this or another forum.

You have to remember that the lower notes are much less directional than the higher ones. Thus the player may hear more of the base notes because they radiate in all directions, whereas the trebles are radiated away from the top out to the front of the guitar.

Ideally then to judge the balance of a guitar one should get someone else to play it and then sit in front at a reasonable distance so you get the full soundscape. I am ignoring all the effects of the playing space though this can come into it as well.

Dave

Try monel or stainless steel E, A, D, G strings.

Every three years at the Guild of American Lutherie conference there is a session called "Steel String Listening". Builders submit a guitar, they are tuned by one person and another plays the same thing on each one. The builder describes what he/she has built.

There are typically 35 or 40 guitars, and because of modern building trends, almost all of them are some sort of smaller fingerstyle guitar (usually OM's). At the last conference there were two dreadnaughts presented, one slightly smaller and one made from an unusual wood (myrtle?, sycamore? I don't remember). What was very noticeable was that they sounded like dreadnaughts.

So you probably can't make much difference it the overall balance, but changing strings is the cheapest and easiest way to experiment. Try lighter and heavier strings (generally heavier will drive the top harder so I would tend to put heavier on the first two or three and maybe lighten up the 5th and 6th. Also, string composition (80/20, PB, others) can have an affect on the sound, you might find one brightens up some frequencies or mellows others.

I would suggest, however, that if you are going to experiment with strings that you record it with each set (and play the same things) - comparing your recordings will help you decide which you like the most.

Another way to think about it is that using heavier strings might exert more tension and "tighten up" the top, causing less of a bass response. The fingerstyle guitars I build are usually more responsive with light gauge strings rather than medium or heavy.

Peter, do you like the guitar?
Sometimes we put excessive influence on the opinion of others, and discount our own. If you have enjoyed that guitar for a while and never heard a problem, don't get put too off balance by a one-off comment from someone else.

Yes - by all means try different strings as an easy variable to modify. But in the end you might need to accept that this is the character of this instrument. Not bad; individual. It won't be all things to all people.

It is like your kids - they don't have all of the characteristics you might have wanted to see in them but you should celebrate each of them for what they are. This is why you should make a bunch more of them (guitars, not kids) and enjoy the different character of each of them.

Mark, do I like this guitar? Indeed I do. My GS Mini, played in the same place by the same player, seriously lacks sustain and resonance compared to my lucky accident. It's my first all-scratch-built guitar. My query wasn't aimed at correcting a wrong; it was intended to explore how to influence volume using string characteristics. Folks talk a lot about altering braces, but I was wondering if altering voice could be done selectively through string selection.

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Peter Havriluk

Silk and Steel strings definitely have a different voice which is more muted and mellow and less booming in the bass. They would cost you some of the sustain however. Worth a try if you are into a folk and fingertyle vibe, but not a rock or country player’s preference.

"My query wasn't aimed at correcting a wrong; it was intended to explore how to influence volume using string characteristics. Folks talk a lot about altering braces, but I was wondering if altering voice could be done selectively through string selection."

This is a topic worthy of it's own thread. String composition and their gauge has a great affect on the sound of an instrument. What I have noticed is the composition of the strings influences the tone color or timbre and the gauge affects the tension placed on the top, which then has many effects on the sound and playability of the instrument.

Lighter strings would likely bring it down. You may however want to take what your instructor said with a grain of salt. I suppose it depends on playing style and taste but I've never met an acoustic with "too much". I hope you have documented how you achieved this feat! Please share!

I've got a near twin to this one assembled right now. I'll soon see how they relate to each other. Same species of wood in both. Same sources for the woods. Both tops were tap-tuned at the same time. Big difference between them is a half-inch variance in scale length. New one is the longer of the two. Bracing adjusted out of consideration for the scale length and bridge support.

We'll see soon.

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Peter Havriluk

As has been said, bass-treble balance is largely a matter of how big the box is, at least IMO. Dreads sound like Dreads, and not like Jumbos, because of the shape, in part, but they both have the 'big box' sound.

One simple way to alter the relative balance a bit is to change the mass of the bridge. Adding mass cuts down on the output at all frequencies, but more so in the treble, so it makes the balance more 'bassy'.

If you want to do a bit more work, you might try shaving the back braces. That's often the best way to bring up the bass on a smaller guitar. A lot depends on how stiff the back is now, of course. Finding the 'main top' and 'main back' tap tones will tell you if it might work. Hold the guitar up by pinching the end of the fingerboard and the UTB between your thumb and fingers. Your hand should block the hole pretty well but without touching the top if you can help it. You have to block the hole to kill the 'main air' resonance, which would mask the higher pitched top and back tones, and also couple them together, which alters the pitches. Tap lightly on the bridge in the middle with the ball of your thumb and listen for the tone; you should be able to get a fairly clear impression of the pitch. Still holding the guitar, tap lightly in the middle the back in the same way. You may have to move the tap point up and down the center line to find the lowest clear pitch. Basically, when the 'top' and 'back' tap tones are very close together in pitch they will work together to drop the 'main air' resonant pitch, and also make it stronger. Since the 'air' pitch is the lowest resonance that can effectively produce sound this will tend to increase the bass presence.

You won't need to actually shave braces to get an idea of whether this will work. Just get some poster adhesive and slap a wad of it onto the outside of the back. Pick a spot over one of the back braces where you can get a pretty clear tap tone. The added mass will drop the tap tone pitch, the same effect you'd get from shaving the brace. It may take a bit of effort to find the best place. Platy it yourself, and also have somebody else both to play and listen, so you get a better all around reading.

Once you've found the pitch that gives the tone you like best, simply carve away on the brace(s) until you get that same pitch. Take wood off the center of the brace, not the ends: it's far more effective. Stop often and play the thing. Use the 'rule of half': do half as much as you think you want to , and sleep on it before doing any more. You can always take off more wood, but even when you number the shavings it's hard to get them all back on in the right places.

There's a whole lot here for my weak brain to process. But it's fun, and I have a high-class problem according to me anyway.

Taking a different tack on strings, if I were to leave the three upper (E,A,D) strings alone and use heavier G,B,and E strings , am I moving toward making the treble louder? I realize I'm dealing in oversimplifications, but I'm curious if I'm going down a path that might yield up more treble and leave the bass alone.

Thanks, folks.

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Peter Havriluk