Posts tagged speaking length

Piano String… Repair or Replace?

I was introduced to the concept of repairing bass strings only 5 years ago.  A fellow tech friend of mine showed me this simple knot in order to ‘save’ a bass string.  Now before i get down the path too far, some of you might be thinking…’well why not just throw it out and replace with a new string?’  First of all, it it’s plain wire, you do.  Plain treble wire is readily available and there’s no magic in the wire.  When it comes to the bass strings however, they are custom made for the size, model and scale of each piano.  The core wire, the copper winding, the length of the copper and the speaking length all come into play.  You don’t just pick up the phone and ask for a new one… especially when the company has been out of business for 60 years.  In addition, a new bass string will not carry the same ‘weathered’ sound as a the more brilliant brand new string.  Aged strings tend to be duller.  So there’s a lot to be said for splicing a bass string.  This knot (shown in a diagram and also picture) tightens up wonderfully.  There are a few criteria however…

1. The break cannot be in the speaking length.  That’s the part where the string sings.  A knot will inhibit vibration.

2. You must have enough steel to make the knot.  Most recently i went to a home where there was a broken bass string and although i was hoping to splice, the broken wire only had about 1/8″ or about 5mm before the copper… not enough to work with

I usually use brand new wire of the same core thickness at the tuning pin because if it has broken once, it’s probably brittle enough to break again.  Once tight, the string usually acts as normal and you can once again listen to the bass with a continuous flow or sound rather than one note ‘jumping’ out at you.

When in doubt just say “Duplexing”

Duplexing just sounds complex. Complex means it’s complicated. Complicated must mean that you’re somehow smart. And so… (follow the trail) knowing about duplexing means you’re smart. Ha ha. If you’re ever at one of those hors d’oeuvres-type parties and everyone’s dressed in tuxedos and ballroom gowns, you’re going to want to have something to say when they ask your professional opinion about the piano. My advice? Nod… add a few “mmm-hmmmms” and say “Ahhh… Duplexing”…hee hee. Ok enough of my jesting…

So what exactly is duplexing anyway?? Created by the late great Mr. Steinway himself in 1872, it was designed as an ‘added ring’ to pianos – giving more resonance to the tone. How is this accomplished? Glad you asked. Any piano string has what is called ‘speaking length’. This is the live portion of the string which resonates freely when a note is played on the piano. The speaking length starts just past the tuning pins on a part called an agraffe (or capo d’astro… ok i’ll define those some other time) and ends on the bridge. Past the bridge, the string is then wrapped around some sort of termination pin. The tone past the bridge was traditionally considered ‘dead’ tone. But Steinway thought “what happened if we kept this part of the piano ‘live’ or ringing in harmonicity with the instrument”? And so the duplex system was born. Think of it as duple time… duple by definition means ‘double’. So duplexing then is a double ringing part on the piano. How did Steinway make this contraption? He rigged another ‘bridge’ just before the termination point. One that was made out of a series of bars. In fact, if you want to test out the duplexing on your piano (if you have it), simply look past the bridge (which is easy to see on a grand piano) and you’ll spot the parts that are called “Aliquots” (another great party word after you’ve used duplex). You can test how live the duplex is on your piano by simply strumming that portion. An aliquot on a piano is a bar shown in the pictures here. By definition it means “fractional part”. Stands to reason… since we’re adding a fraction of the sound to the tone. In Latin, it simply means “several” or “a few”. Steinway’s thinking was to add either an octave or 5th to the existing tone, making it fuller and richer sounding.

Having said all that… some people just don’t like the extra ring. Solution? Simply cordon off the strings with what is called ‘understringing braid’. (I know i know… too many new words this time around). In the tech world, it’s simply called understringing – anything touching the strings will stop the extra tone and so if you have a technician ‘block’ the tone by adding understringing, it will alter the added ring on a piano. By the way, one experiment i did about 5 years was change the proximity of the understringing with the bridge. It changes perceived tone considerably.

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