What is a Bridge?
The two strips of wood running down either side of the dulcimer on which the strings rest and pass under are called the Bridges. The left-hand Bridge is called the ‘Treble Bridge’ and the right-hand Bridge is called the ‘Bass Bridge’.
The Bridges are not fixed down to the face of the instrument. They are merely held in place by the pressure of the strings that run across them.
Why is the Treble Bridge position important?
The Treble Bridge is designed so that you can play the strings on BOTH sides of the Bridge. The corresponding notes on the left and right side of the Treble Bridge are always tuned a fifth apart. In order for this to be possible the Bridge is placed in a very precise position. This also enables accurate tuning on both sides of the Bridge.
The only way that both sides of the Bridge can be simultaneously in tune is if the Bridge stays in its exact position.
The Bridge should ALWAYS run in a STRAIGHT line from end to end. If its position alters even a fraction then the two sides of the Treble Bridge will not tune to each other.
*Note: Some Dulcimers are specially designed so that you can play BOTH sides of the Bass Bridge. In this instance it is also possible for the Bass Bridge to shift and need adjusting.
How do I know when the Bridge needs adjusting?
If you are having difficulty getting both sides of the bridge to be in tune at the same time (i.e. when one side is in tune but the other is sharp or flat), then you may find that the bridge is out of line and needs adjusting.
There are other reasons why you might be having difficulty bringing both sides of the bridge into tune, and adjusting the bridge should always be a last resort. Check the tuning page on this website to see other tips on how to bring the strings into tune.
I think My Bridge needs adjusting. What should I do first?
Before you attempt to adjust the Bridge, you need to determine which end of the Bridge has shifted, as this is the end that you will need to realign. Wherever the Bridge has shifted, is where you will have un-tuneable courses on your Dulcimer.
In my experience it is more often the top end of the bridge that shifts a fraction to one side or the other, resulting in the top couple of courses being out of tune. If this is the case then it is only the top of the bridge that will need adjusting. However it is possible for the bottom end of the bridge to shift and in rare cases the whole bridge can shift meaning both ends will need adjusting.
You will need a tool to tap the bridge into place. I find a metal ruler works well. Be extremely careful when using your tool, as the Dulcimer Bridge is fragile and can be easily damaged.
So how do I adjust the Bridge?
Basic guideline: Locate the course(s) you are having problems tuning. Bring the right side into tune and check the left side.
If the right side of the Treble Bridge is in tune, and the left side is flat, then the Treble Bridge needs to be moved to the left.
If the right side of the Treble Bridge is in tune, and the left side is sharp, then the Treble Bridge needs to be moved to the right.
Here are the steps I use to adjust the Bridge:
1. Locate the course(s) on the Treble Bridge that needs adjustment.
2. Make sure that the right side of the course(s) in question is in tune.
3. Check the tuning on the left side.
4. If the left side is flat, then place the Ruler on the right side of the bridge, directly below the course and against the bottom of the bridge. You can place a leather pad or other protective material between the Ruler and surface of the Dulcimer.
5. Gently tap the Ruler with enough force to move the bridge a tiny fraction to the left. A very small fraction of an inch will make the difference between “in balance” and “out”.
6. Retune the right side of the course in question, (as this will now have altered) and check the tuning on the left side. Repeat this procedure until both sides are in tune. If you move the bridge too far you will need to bring the bridge back again by repeating the process from the other side of the bridge.
7. Check all other courses to make sure that you have not knocked any other courses out of tune to each other.
Remember that flattening one side sharpens the other and vice versa. Each time you move the bridge you must check the tuning of both sides until they are both in tune.