Strings

There are a number of basic principles of instrument construction and resonance/signal physics that seem to boggle the average musician, and therefore are taken advantage of by companies and salespeople to unload junk on you. I’ll try to make some sense of them here. Now, these apply mostly to guitar and bass but many of these ideas are also every bit as relevant in percussion, orchestral and wind instruments. Knowing these will help you decide on the right gear to buy, or what modifications to make to current instruments to get them closer to perfect!

Feel free to ask anything, I'll be glad to answer anything I can!

 

Strings

#1) Glue is the Enemy! Ok, here’s the test – take a glob of glue, a bolt and a slab of maple and drop them from shoulder height. Which is the most resonant? The bolt will chime nicely, the maple will produce a good, solid tone and the glue… well… it doesn’t make any sort of appealing sound, does it? Considering that resonance originates from the neck and bridge (about 70% neck and 30% bridge) and that the body is used to amplify (in acoustic instruments) or feed the sound to the pickups (in electric instruments) the neck joint is the most important place where this can have an impact.

Ideally, all instruments would be made from a single, solid piece of wood, but that’s extremely difficult in the modern world with smaller trees and CNC routing and all. So the best real-world solution is a solid neck-through instrument with a one-piece top/body-wings assembly bolted on – In that situation, the strings would be attached directly to the neck wood at both ends along with the pickups and the bridge would be attached to the body, making it resonate and adding directly to the tone. Glued on body sides like Rickenbacker and Carvin use are almost as good, but don’t fully utilize the body sides to increase resonance (the glue blocks high-frequencies and robs energy from low frequencies).

The second choice is a bolt-on neck. The most important thing to make sure about on this type of instrument is that there’s no glue, paint or plastic between the neck wood, body wood, neck plate, bridge and pickups AND that the neck joint is as airtight and as tightly fitted as possible. Godin guitars (and numerous boutique makers like DeTemple, Tyler and Suhr) are the best example of a bolt-on guitar done properly.

Then there’s the set-neck… Once again, the glue in this type of construction acts as a barrier for higher frequency resonance and hinders the transfer of low frequencies. Since most resonance starts in the neck and moves to the body, this is a BIG deal! Sometimes this can be a choice made to achieve a less biting sound (especially when using woods with extremely high-frequency resonant qualities like maple and ash). In some guitars (especially those using mahogany, or other bass-focused woods) it often lends to a muddy tone where individual notes tend to be rather undefined because the high-frequencies from the neck are unable to get to the pickups and the low-end has energy robbed from it as it makes the transition from the neck to the body. Many guitars try to minimize this effect with maple tops to create more high-frequency waves in the body, but it simply doesn’t work as well as utilizing all the energy from the neck.

SMD Drums has a wonderful article on this subject on their site where they calculate the amount of glue on ply vs. stave shells (2,373 square inches vs. 24 square inches). This is why single piece shells have been making an appearance lately (Tama made some as a limited issue a couple years ago and many of the boutique makers have been doing them as custom jobs). So this is just as relevant to percussionists.

So what can you do to use this information? For set-neck and bolt-on players, the biggest thing you can do is to remove the neck pickup (for set-neck) and see how tight and clean the neck joint is, or simply look at the gap around the neck on a bolt-on… if it’s loose or sloppy don’t buy the instrument, this is something that really can’t be fixed! For bolt-on players, you can also make sure there’s nothing in the pocket hindering full wood-on-wood contact (paint slopped over into the pocket, glue from multi-piece bodies, labels and stickers, etc.). Some bolt-on guitars have a screw or plastic shim that puts the neck in the proper position… TAKE THESE OUT AND REPLACE THEM WITH A PROPERLY FITTED WOODEN SHIM!!! You will be absolutely amazed at the difference these simple cleanup jobs can make.

For all guitars – Make sure the pickups are bolted to wood or metal, not plastic pickguards or pickup rings. On my Fenders, I remove the paint from the pickup routs with a dremel tool and bolt the pickups to the body using maple spacers to adjust pickup height. For guitars with pickup rings, there are metal and wood rings out there or you can do the body-mount thing. This also applies to glue joints within the body, so take a close look at the back and edges of the body for seams – I’ve seen custom shop Gibsons with 7-piece mahogany bodies, and I’ve seen Squires with 1-piece basswood bodies… having all those joints completely eliminates any resonant advantages mahogany has over basswood.

Strings

#2) Choose Your Wood Wisely!) There are articles all over the place that tell you about the tonal personalities of different woods. That’s not what this is about. Consider the structural characteristics of different woods. There are numerous qualities of woods that you should consider when choosing the right instrument.

The first is flex vs. shatter. This is most obvious when it comes to instrument necks. Mahogany and maple are the two most suitable woods for necks due to their density and resistance to collapse under string tension (rosewood is also good, but is far too rare and expensive to be realistic in most cases). The main difference, structurally speaking, is that, when smacked around, maple flexes and dents whereas mahogany cracks and shatters. Think about how many old Fenders have dented up necks and how many Gibsons have had split or broken necks and headstocks! I personally repair 3-4 mahogany necks a week (at $200+ a pop) and remove dents from someone’s maple neck about once a month (for about $40).

Moisture content is the second big deal. Members of the alder, basswood, poplar, aspen family and other swamp-dwelling trees like ash and tulip have extremely high water content, that, unless properly dried before crafting, can lead to serious cracking and will generally have dead tone (try hitting an empty bucket vs. one filled with water and see which resonates better). Softwoods like pine, spruce and cedar are a little bit drier than the previous group, but let go of their moisture more quickly, thus they crack very easily. Then there’s the non-nutbearing hardwoods like maple and mahogany that have moderate moisture levels and dry fairly well. Nut-bearing hardwoods like walnut, oak and hickory tend to be very dry… and then there’s woods like ebony, rosewood and ironwood, which have almost no water in them.

Another interesting property of wood is that it grows in a spiral because of the spin of the earth, just like water spiraling down the drain. You can most easily see this by laying under a pinetree and looking up at the pattern of the branches… it’s usually a pretty obvious double or triple helix. This causes the wood, when under longitudinal pressure, such as string tension, to naturally untwist causing splits or twists in the neck. Maple, ebony and rosewood are the best at resisting this twist. Another interesting thing is that mixing woods from north and south of the equator the twists resist each-other and prevent neck warping! This is why Fender necks with northern-hemisphere maple have either a southern hemisphere rosewood fretboard or paduk skunkstripe. This also works with laminate necks like many basses (and guitars like Rickenbacker, Carvin, Alembic, American B.C. Rich…) have.

Strings

#3) Solid Anchor) Bridge designs… how many hundreds are out there? Like I said above, 30% of your resonance gets to the body through the bridge, so it’s important that this is as solid and efficient a connection as possible. There are a few main things to focus on when considering this aspect of an instrument.

First is design. Look at various type of bridges and how solid their connection is to the body… Most are terrible, some for a good reason, some just because it’s cheap or traditional. When looking at a bridge, think of sound as traffic trying to get from the string to the body – if there are choke points or breaks in the road surface it’s tough as heck to get where you’re going! Look at tremolo (more correctly called vibrato) bridges. The standard Fender style makes contact with the body at two or six knife-edge points. Obviously the six-screw type has a more solid connection, but it’s still pretty weak. Then the tune-o-matic… although the bridge design itself is cool, all the resonant energy has to travel through a pair of scrawny little legs. The archtop style is better with a pair of fairly solid style feet, so long as the particular bridge doesn’t share the tune-o-matic’s weakness. The best type you’ll normally see out there is the Fender style hardtail or Tele type bridge. It has a very solid footprint bolted directly to the body wood while still allowing for a wide range of adjustments for each string. Other good designs are the newer style bass bridges where each string has it’s own, individual bridge piece, and, my personal favorite, the Weber Brekke bridge (check it out at www.soundtoearth.com). I use a modified version of the Brekke bridge on the instruments I build. There are also a new generation of tremolos using ring bearings which make a much more solid connection than the old-style trems. I’m liking these designs even though I think they still need a few more years of development.

The second aspect that’s going to make a difference is mass. Strings have very little mass and therefore have a hard time making a high-mass bridge resonate (since momentum is mass x velocity). One way of making a bridge low-mass to make it small – a Fender vintage trem blows a Floyd Rose out of the water in terms of resonance. Or to make the bridge out of low-mass, but still hard and resonant, materials. Wood is the best solution, but is subject to wear and breakage… seeing how many people treat their instruments it often isn’t the best way to go. Jazzboxes usually have wooden bridges because it’s assumed that they will see the least abuse, so they can afford to go with the wood. Barring that, aluminum, brass and titanium are the way to go. Titanium is new to the scene, but I think it’s going to take over in short order. Brass was big in the 70s and early 80s and is still big with the bass crowd as evidenced by Warwick and Ken Smith. Aluminum, although great for resonance is subject to wear and breakage, not as much as wood, but it’s still a factor. Rickenbacker and Bigsby are the only companies I know of that use aluminum. Steel is by far the most common due to it’s strength, cost and, most importantly, it’s image with the common public. People see it as strong and reliable, and although it is, it’s relatively high-mass doesn’t lend itself to this purpose as much as other materials… AND many companies out there are using lesser, softer grades of steel that are REALLY bad. One way to test if you have a lesser grade of steel is it’s magnetic properties… if a magnet sticks to your bridge, you’ve got a cheapie! Graphtech saddles are a great way to reduce mass and increase hardness of a bridge cheaply and easily... plus they are slippery as heck and greatly reduce string breakage! If you have a Fender bridge, I'd also check out DeTemple Guitars, they have a retrofit titanium bridge that sounds great.