What About The Bass Bridge?

Many upright bass players looking to buy an upright bass, an upgrade or even their first bass, hardly ever think about the piece of maple holding up their strings on the top. No matter how incredible or valuable the bass may be worth, if the bass bridge is not the right size, the right fit, or even the right type, it could seriously alter the whole character of the instrument.  While the most important responsibility of a bridge is to safely hold the strings at the proper height and spacing, it "bridges" the sound of that vibrating string onto and into the body of the bass.  I have personally heard so many incredible differences in tone and responsiveness by even the slightest changes in the bridge.  There are two major companies in the world that specialize and sell bridges: Aubert and Despiau (both based in France.)  Another company, Teller, is based in Germany is slightly cheaper than the French ones, but most prefer the French and will pay more for them.

What makes some bass bridges more expensive than others?  First, both Aubert and Despiau grade their bridges by the quality of the grain (medullary rays) that appear on the top of the bridge grain.  While the 'grainier' wood costs more, it isn't actually harder, so they tend to sound the same, regardless of super dense grain or wider (less) grainy.  Despiau grades their bridges by the grain type and appoints 3 trees (stamped) on top, 2 trees, 1 or plain, no tree (for student or cheaper instruments).  Again, the tree stamps really denote the attractiveness of the wood.  Also (as Despiau) says on their website, the older stored seasoned wood costs a premium as well.  The wood should be old enough that it won't warp easily after being installed and will hold up for many years.  On our Thompson upright basses (both plywood and hybrid models), we use choice wooden bridges: Very dense, solid (treated) maple.  While the wood comes from China they are special ordered from a specialist source and are the best maple bass bridges you can find.  We use our favorite Aubert pattern for the Thompson basses and we can hear a nice difference: They tend to have a lower fundamental and punchy response. 

Even the thickness or shape can change the sound and response of the instrument.  In most of the world, (with the exception of USA and Canada), upright bass players tend to not use any kind of bridge (height) adjusters.  Like their smaller instrument brethren (cellos, violas and violins) you'll hardly ever see any kind adjusters on European players' basses.  While the percentage of seasonal changes are the same, 4% on a bass is far more noticeable on a bass than it is on a cello!!  In the summer where it normally gets more humid, the strings almost always go higher on the instrument.  Some cellos can change so much that some players can go between two bridges throughout the year so that the strings won't be too hard to play on in the summer or too low in the winter.   In Europe, some bass players also will use two bridges and here, (in the USA) many fully carved basses do well with a winter AND a summer sound post for this very same reason.  For the ones that elect not to use adjusters and where the climates are more seasonal, they need two bridges: A shorter one for the summer and a higher one for winter. For people that set up basses and work on them all day long...it still never ceases to amaze us how much character can be altered by the shape and thickness of the bridge. 

At the moment of this writing, we received a beautiful French Thibouville Lamy Bass (circa 1890).  It came with a pretty ugly, crude bridge though and that was the first thing we changed on the bass.  First, when the bass arrived, it immediately sounded beautiful:  Nice tone, not bright or edgy sounding like some French basses can be, but had crude looking old aluminum bridge adjusters and the feet didn't even fit right!  We put a nice Aubert bridge and our special Delrin (black) adjusters. 

When first selecting the bridge size, the bridge (bass bar side) foot should be centered right over the center of the bass bar.  If you do not know what a bass bar is, it can be found inside the bass top, right next to the f hole (E string side).  The center of the bass foot should be centered right over the middle of the bass bar on the inside of the bass.  The other foot of the bridge is then usually placed so that it is equally distant from the other side from the f-hole (on the G string side.) as is the E string side.  Sometimes even the best, most incredible basses can have an off center and/or off kilter neck placement so that fitting the bridge properly also has to wrestle with the placement of where the neck is placed!  Every bass is different.  Usually for a 3/4 size bass, the typical bridge width is 150mm, though by careful placement and measurement, if the bass bar center requires a slightly wider bridge, say 154mm can really add to the lower end quality of the bass.  Again it depends on where the bass bar is inside the bass.  By adding a bridge that is too wide is just as bad as one that is too narrow.

Getting back to that Lamy bass!  Changing the thickness of a bridge in either direction can have astonishing results (both good or bad!)  When fitting a new bridge, we first fit the bridge perfectly and also with the same exact optimal playing height that we want on the bass.  We then play the bass (without the bridge adjusters installed yet!!!) to first get the exact sound we want, the tone, and to see how the bass responds.  Only after we are happy with the way the bass is playing, do we then install the Delrin bridge adjusters.  On the Lamy bass, the new bridge was thicker than the original one that came with the bass.  The bass seemed also a little fuller (bigger) sounding, but at the same time, I noticed the G string a bit tight and not as responsive.  So, starting with a fatter bridge is preferable because we can always go less and less, but it's very difficult to add any wood back on!  A bridge that is too thin can easily warp and loose a little power or definition.  A bridge that is left too thick can have the opposite approach: Too bright sounding, and while there might be some additional feeling of lower end power, might also take off the response of the high string(s) or higher registers.  Everything is tradeoff and it is always fun so that when a player knows his bass well, to play it with the his/her luthier to find the 'sweet' spot. 

More about the black Delrin adjusters.  Delrin is a self lubricating, high density material and it will never bind inside of a maple bass bridge.  Anyone that has experienced those super tight aluminum adjusters knows how hard it can be when trying to get them to turn when the bridge has dried a little or shrunk in the winter.  This is why we see so many chewed up looking bass bridges because the player has had to use plyers on the adjusters and they always catch the wood and chip it off.  Also, we find that Delrin interferes less and matches the acoustical wood properties better than aluminum, whereas brass tends to even mute the bridge and vibration.

Why most players do not use bridge adjusters in Europe?  I think...mostly, it is out of tradition, but they (Europeans) rightly ascertain that the adjusters can interfere with the sound of bridge and the bass.  I have personally kept and played on my own bass without using bridge adjusters and the hassle with the changes in Phoenix (winter) proved too much for me to want to keep it that way.  I like to play on low string height and so when the bass shrunk in the winter the strings got so low that they buzzed.  Back went the bridge adjusters!  To be honest, strangely to me, I kind of liked the way my bass played with the bridge adjusters in more than without!  For some odd reason (my G string felt more 'stubborn') and edgy without bridge adjusters and then when I added them in, the problem went away, but the bass still sounded pretty much the same everywhere else.  Some swear that by playing without the bridge adjusters is the purest and only way to go.  That is maximizes the tonal and playing spectrum of the instrument, whereby the adjusters can potentially interfere with some of that.  Maybe so, but on most basses it seems to be a negligible amount.  (My opinion....)  The adjusters can really make a huge difference and besides the obvious playing height, also change the pressure and tension on the bass which can also 'play' a role in the end result of the tone and response.  In the end, there's no right or wrong answer or perfect solution.  Every bass is different and each player has his own idea of what he or she likes or needs the bass to do.