In the last post I talked about some easy surface preparations for piano, but I didn’t mention that there’s a long history of these. Some early piano makers experimented with creating “stops” for their instrument that would change the timbre of the piano. Many of these were essentially mechanisms for surface preparations. The bassoon stop, for instance, lowered a parchment roll (or a parchment roll covered in silk) onto the strings, producing a gentle buzzy sound against the strings when notes were sounded by the keys, much like the surface preparation of placing paper on the strings of the piano. (No I don’t know why folks in the 18th century thought this sound = bassoon.)
Even some modern upright pianos, rather than tying a sostenuto mechanism to the middle pedal, instead install a “practice mute.” On these instruments, pressing the middle pedal lowers a curtain of wool felt between the hammers and the strings, reducing the volume of the instrument.
With a few exceptions, there aren’t a lot of current piano makers who are offering stops on their instruments such as the bassoon stop, so it is up to individual players and composers to dream up their own surface preparations and discover other timbral resources for the instrument.
Here is one more easy and safe surface preparation, which I’ve saved for last because it requires some work. This is for a weighted, cloth-covered mute. This mute has several things to recommend it: since you build it yourself, you can customize each mute to the length you need, and it will cover the number of strings you’d like; it’s cheap and easy to make; it goes on and off easily, and it is safe to use on the piano strings in any register. It’s easily my favorite mute, as it’s totally consistent: place one of these mutes on a set of strings, and it dampens the sound of every string.
I first heard about this mute from composer Stephen Hartke, who made some of these mutes with children’s socks and ordinary filling materials and used them in his piece Meanwhile (2007) written for Eighth Blackbird. Jennifer Jolley also heard about Hartke’s mutes and has blogged about making these herself. (Note these make an excellent composer task-avoidance project! Jolley remarks that adding googly eyes is optional.)
Here’s the basic idea: fill a sock with BBs or dry rice or other weighting material. Sew the end of the sock closed. Wrap the sock in another sock and sew it closed as well. And then probably enclose all of that in one more sock and seal. Finis.
Rather than using socks, which I had trouble filling all the way to the top and, since I was sewing each layer separately, I ended up with an end of the mute that didn’t mute so well, I’ve made a very slight modification. I start with two layers of t-shirt fabric, shape this into a single thick cylinder about two inches across, and double-stitch the end of the layers together. I fill that cylinder with BBs (leaving a tiny space at the top, so the mute will bend and curve easily), then double-stitch it closed, et voila, my own custom mute. Without a specific piece in mind for these, I simply made a variety of lengths, so I have one for just about any piece.
Now for a few simple and safe string preparations. The surface preparations—resting light objects on top of the strings like the paper, aluminum, and cloth items that I’ve talked about thus far—are the safest (and probably the least “scary” to new experimenters). String preparations, which involve inserting foreign objects between the strings, may be a little more intimidating, and there is indeed more opportunity to do damage with these. But, by approaching with care, there are lots of string preparations that you can try without causing any harm at all to the instrument. And, these can open up many additional sounds from the piano.
First, the protocol: Again, start with clean, dry hands. Next, you have to protect the delicate felt of the dampers, so before inserting or removing anything that you’ve previously placed between strings, always first press and hold the damper pedal down, lifting the dampers off of the strings. This prevents your lateral movement of the strings from scraping or compressing the damper felt.
Don’t try to insert anything close to the dampers, or within a couple of inches of the ends of the strings. Richard Bunger in The Well-Prepared Piano warns never to insert anything that doesn’t flex within an inch of either end of the string, and this is very good advice. Let’s play it super safe and, for now, don’t insert any string preparations at all within two inches of either end of the string.
One thing this means is basically no string preparations for the very highest register where the strings are very short and stiff. Also, it’s safest when you’re getting started trying these to avoid the more delicate wound strings of the bass register. Best to try string preparations nearer to the flabby middle of the steel strings in the middle register.
Next, in order to insert most items, in addition to releasing the dampers, you should gently move the two strings apart before placing the preparation material between those two strings. There are lots of items that pianists over the years have used for this. I recommend using a (dull) plastic children’s knife. (A bamboo wedge works very well, also, but plastic children’s knives are easy and cheap to come by.) Lots of pianists use screwdriver blades for this, but plastic is much safer to use than steel. After depressing the damper pedal, place the blade between the two strings, pivot it so that the knife edges gently push the strings apart, place the preparation in between the two strings, then pivot the knife back to release the strings onto the preparation. Then you can release the damper pedal, and check the note.
For a first string preparation, try plastic straws. You can experiment with the difference in sound between preparing with a straw between strings 1 and 2 and nothing between strings 2 and 3 of a unison set, and straws both between strings 1 and 2 and also between 2 and 3. Then try this: place a straw between strings 2 and 3 only. Play the note. Then depress the una corda pedal (left pedal) and play the same note. Cool, right? Since the una corda mechanism moves the action over so that the hammers hit fewer strings in the multiple-unison sets, now you have two different prepared piano sounds available at one key, using only the pedal and a single straw!
Next, try rubber piano tuner’s mutes. These rubber wedges are very gentle on the strings and transform the piano’s ordinary notes into a lovely muted thunk. Since these are soft and wedge shaped, you don’t need to use the children’s knife to insert these—just press and hold the damper pedal before inserting or removing, to protect the damper felt from getting squeezed by the pressure of inserting/removing the mutes.
You could also try wood golf tees. (Try the trick with the una corda pedal with these too!) Rubber cap erasers are also nice—cut a slit across the bass of the eraser and snap that over the middle string of a set of triple unisons. This will modify the sound of all three strings.
Once you’re feeling brave, you could next experiment with some harder materials as string preparations: plastic screws, plastic screw anchors, wedges of bamboo, one jaw of a wooden clothespin. These all work as string preparations, can produce some very interesting sounds, and you can use these on all the strings that are sufficiently long for preparing purposes.
And once you’ve tried all of these, and a built up a familiarity and a comfort level with them, you could try some metal items. Safest to restrict these to use with the flat steel strings, and safest to use soft metal items—small copper tubing, brass bolts and screws, aluminum machine screws. Best to avoid steel, and not to use any metal (or anything with a sharp edge) between the delicate wound bass strings.
I like Anna Thorvaldsdottir’s instructions in her piano solo scape (2011): the score indicates that eight specific mid-register notes should be prepared with screws, and says that the resultant sound should have a “’gong like’ quality,” but she leaves the size, materials (Steel or, even better, brass? Could I get away with hard plastic screws?), and the size and type of screw completely up to the pianist.
Now, obviously, John Cage’s prepared piano works don’t limit themselves to what I’m calling soft metal items. And, I will freely acknowledge that there are some wonderful sounds available by inserting steel bolts of various lengths and diameters, and bolts with additional nuts, or with nuts and loose metal washers kept in place by the nuts to add a rattle to the sound. But, I would not recommend that these be used for the wound bass strings, and great care should be used when inserting steel items even on the steel strings. Save experiments with hard metal items for once you’re thoroughly comfortable with the other string preparations I’ve covered, and consult with a professional before trying these at home!