Whether you call it string, line, wire, or cord, the thin, flexible linkage between your valve levers and your valve rotors is your lifeline to a properly functioning horn. This thin line has advantages that cannot be duplicated (a smooth action throughout the lever’s travel), as well as flaws that some consider fatal (a tendency to break).
If your horn has a string linkage then the composition and properties of that string are of paramount concern to you, but many horn players never even give it a second thought. That is, unless it breaks. And Murphy predicts this catastrophic failure will most likely occur during a concert. So before you live the nightmare of forced use of alternate fingerings, choose the string on your horn wisely.
What makes a good string for your horn?
A good horn string should be as lightweight and thin as possible without being prone to breakage, strong enough to take the pressures involved, easily installed and knotted, resist slippage, have a low stretch coefficient, and be able to resist the lubricants that one uses.
The thinner and lighter the string is, the less friction there is while operating the valve levers. Less friction means a smoother, faster action. But thin and light strings tend to be weaker, so you have to balance this against the strength (usually measured in test pounds) of the string. Action is also affected by whether the string stretchs under load, so the less stretch the better.
Many horn players use the Yamaha brand string (the yellow string), which has all of the desired properties and is readily available. I prefer a variety of fishing line known as black, braided Dacron squidding line which is pretty hard to find these days. I have it in various test strengths (30 lb, 50 lb, and 80lb) of which I prefer the lightest. The higher strength strings are correspondingly thicker, with slower action, but don’t break as readily.
Breakage and slipping
Speaking of breakage, I find that 30 lb test is strong enough to resist the strength of any horn player’s fingers. Strings that break (and especially if they break habitually) most often break because of sharp edges that cut them on the levers or screws, and not because of any inherent weakness in the string.
In general the best strings to use on your horn are various braided synthetic fishing lines. The hard part about finding good string is finding string that does not slip. Many of the commercial fishing lines these days are coated, often with Teflon, and the string will slip no matter tightly you screw it in. There are so many brands and kinds of line on the market that it would be impossible to survey them all.
You can’t go wrong with the Yamaha brand or with the string supplied to most repair techs through Allied Supply. If you have a favorite, I’d love to know what it is.