Piano Tuning in a Nutshell
So you want to tune your own piano, eh?
You'll need a piano tuner's kit:
- a piano hammer (what you tune the pins with)
- a long skinny strip of felt (muting - put in between the outside strings of the 3 string sets)
- 2 rubber wedges (for muting individual strings)
I also like to keep a big guitar pick handy, as well as a couple of screwdrivers and pliers.
The first thing you need to understand is the nature of the tuning pin. It's about 50 cm long with very very fine threads around it. The pin sits in a block of wood called the pin block. Nothing keeps that pin in there but friction.
If the wood block dries out (which it starts doing after about 25 years) your pins won't have the friction to keep the strings in tune.
The first tool to remedy the problem of "slippery pins" is a tool called a "tuning pin hammer". You use this to sink the pins a little deeper into the wood. A couple of whacks is usually all you need (be very careful!).
The second "tool" to remedy this problem is "pin block liquid". Pouring this liquid around each pin causes the wood to swell, which in turn makes the tuning pins seat better. If you have an upright piano, you'll have to lay it on its back, apply the liquid and leave it there for at least 24 hours. This is only a temporary fix and only lasts about 5 years.
Assuming the pins are solid in the block, the manner of actually tuning individual strings is as follows:
Bring the string sharp (not horribly sharp - just a little bit). Now back the tuning hammer off by giving it little hits, you should feel little "cracks" as it flattens. What you're doing is trying to find a place where it "cracks" into tune and there the pin will stay.
This can be infuriating. Hit the hammer a little too much and it slips flat and then you have to start all over again. But sometimes the pin just really likes a place that's not quite in tune and you can't seem to find a "crack point" that's right on the money.
A piano tuner's "secret" is that not all three strings have to be perfectly in tune, a slight difference (which you'll get anyway in a couple of months with regular playing) actually beefs up the tonal quality of the note (chorus effect). However, if it's out enough to really bug you - then you gotta fix it.
Each region of the piano presents different problems. I like to start with the highest double string and work my way down. Generally you get a pretty good response off those strings and since they're doubles it prepares you for working with the triples late on.
If you're using a chromatic tuner, you'll need to know that the higher you go the sharper you have to go. The same is true for the lower notes, they become progressively flatter.
Tune your middle region to 440, but for each octave above that, progressively raise it by about 1 cent. This means that your highest notes will be about 3 or 4 cents sharp. For your lower strings use the same formula, also flatten them progressively by about a cent per octave.
Another thing I should caution you about is the temptation to tune by perfect fifths. The ear will naturally be drawn to a natural perfect fifth. In tempered tuning, fifths are NOT perfect! If you try tuning your piano using natual perfect fifths you'll sound great in one key and everything else will sound like hell. (Which is why they invented tempered tuning in the first place).
Once you've got one of the strings in the set tuned, use the method I described above to set the pin(s) of the remaining string(s) so they stay in tune.
The single string bass notes generally have to be tuned by ear no matter what.
The problem is that with older pianos, the metal tends to crystallize and the harmonics become akin to a bell. Old dead bass strings are a bitch to tune. If this is your situation, just make sure that the "clunk" they make is at least close to one of the main harmonics that correspond to the octave above it.
You'd think that now we've done all the doubles and the singles that the piano's half done, eh? Dream on...
Typically you'll shove the long felt strip in between each set of three strings, and tune the middle one in the set. That works for everything except for the top octave and a half (which has to be tuned by ear).
Start at your bottom note that has a set of three. Tune the middle note. Once you've set it, pull the felt out on the left side. Now you have two strings open that have to be tuned to each other.
While hitting the corresponding key, tune the leftmost string to unison with the tuned middle string. Using "beat frequency", bang the key and tap the hammer until the beats disappear.
Next put your rubber wedge on the left side of the set of strings and pull the felt out of the right hand side. This leaves the middle and right hand strings open. Tune to unison as above.
Pull the rubber wedge out and hit the note. You'll hear all three strings sounding. Something not quite right? This is where I like to go in with the large guitar pick and double check the exact tuning of each string in the set.
Continue on until your chromatic box stops responding. Tune your highest notes to octaves.
Once you're finished tuning it. Play it for a bit. Give each key a few good whacks. This helps to settle the strings and will also make you aware of any problem notes that need another look at.
That pretty much sums up the tuning process. But what if you break a string?
Each string is actually TWO strings. Each (3-set) string starts at a pin, goes all the way to the end of the harp, loops around, and goes all the back up to the pin block where it's in another pin.
Sometimes these strings are 2 out of the 3-set, sometimes they're one out of one 3-set and one out of another nighboring 3-set.
It's not the end the world if you've got one string missing from two adjacent 3-sets, but if you've got 2 strings missing out of a 3-set, it's gonna sound really weak.
Take the string off, cut off any bits that are overly curly. Buy a special set of pliers that you can use to make the correct sized loop for the end of the harp. (Make sure to make a really good strong loop that doesn't slip!).
This way you've "repaired" one string (better to only be missing one string than two!)
When you begin to wind the string back on to it's pin, make sure the pin has been screwed out far enough to be able to accommodate the winding. I'd say screw it out by at least 20 to 25 cms.
Now that we've dealt with the technical aspects of "Piano Tuning in a Nutshell", I'd like to address one more thing.
I still recommend that you get someone else to tune your piano. I say this not so much because someone else will probably do a better job, but even professional piano tuners (if they're players) WON'T TUNE THEIR OWN PIANOS!
The rule is "Never tune your own piano!" This because if you do, YOU'LL NEVER BE SATISFIED. You'll end up spending more time "just tweaking one more little note" than you will playing it.