An unexpected re-tuning

by Edward Schocker

My instrument is glass. Over the years I have found and collected one hundred glass vessels of various sizes and shapes and compiled them into a musical instrument.


I didn’t intend glass to be my main instrument. In 1998-99 I worked at a dance school in Arnhem, Netherlands. I was there to work with two other composers/performers to collaborate with the students and visiting artists on newly created works. As we were developing work that was to go on tour, I quickly realized that we lacked musical instruments at the school and that I needed something to accompany the dancers with. 

The following weekend I found myself in an outdoor market in Brussels. It just finished raining and most of the vendors already packed up to go home. One of the vendors that was still there was a man selling brandy snifters. He had them nicely displayed on a mat on the ground. The glasses glistened from the sun shinning through the raindrops that hadn’t evaporated yet. I kneeled down and started rubbing my finger along the wet rim and they instantly made a beautifully pure tone. I sold the man out, bought every one of the glasses (about 10 in all) and soon found myself back on the train to Holland to start experimenting with my new instrument. 


Back at the school I found a discarded table with a glass top. I used tape to connect the glasses to the tabletop and began experimenting with tuning the glasses with water. I was astonished at how precise I was able to tune the glasses, but it was difficult to take out a pinch of the water if I added too much water. One of the students at the school gave me her eyedropper and that worked perfectly to add or subtract small amounts of water in order to fine-tune the instrument. Once I found the correct water levels, I used an oil pencil to mark them on the glass so it would be easier to refill them. And from there is the basis of how my glass instrument was constructed. Through the years I started to find very large (multi-gallon sized) vessels and the instrument grew to become a 40-piece 3-octave set tuned in a 11-limit Just Intonation. I’m still amazed at all the many sounds and effects that can be produced by this instrument and I continue to learn more about the instrument each time I play it.

Surprise Return

One of the annoyances of this instrument is finding a place to store all the glasses. Currently they are all stored in different places around my house and at a storage space at a school that I’m in residence at. On returning from a project in New York, someone somehow decided to steal my glasses. I assume they didn’t know what was inside the travel cases and just grabbed them from the storage space and somehow hopped a 10-foot fence to escape with the goods. I would have loved to have seen the look on their faces when they opened up the cases and saw what was inside (each case had a glass table top with about 40 brandy snifters siliconed to them).Many thoughts went through my mind in the ensuing days –why did this happen? Should I take this as a sign to move on or should I find a way to rebuild them? It took about 10 years to slowly build this instrument, how could I rebuild it in two months for my November performances at Yerba Buena Center for the Arts and the Berkeley Museum’s L@TE event? After talking with the members of the Thingamajigs Performance Group and other colleagues, I realized this is a great opportunity to learn from the mistakes from building my last instrument and to build another, better designed, one. Fortunately the Foundation for Contemporary Arts thought it was a great idea also, and agreed to fund and support the building of the new instrument.


I started immediately looking for brandy snifter glasses. I find that brandy snifters are the best for the kind of glass playing I do because they have a small stem between the glass and the base. The stems on traditional wine glasses are longer and thinner and always break when I’m playing in a rough manner.

My first stop was IKEA because I knew they had the largest selection of quality glasses. With my electric tuner in hand I tapped on every brandy snifter they had in the showroom (much to the resentment of the employees and customers around me). The glasses were well made but they only had a range of a Major 2nd between the highest and lowest pitch glasses. I ended up buying 20 of them because I knew I could expand that range once I added various amounts of water to them.


Once I had my base pitch-range from the first batch of glasses, I started to scour other stores to find glasses of different pitches. I found brands such as KROSNO, Portifino and Libbey all had higher pitch glasses, and I was able to build the upper octave of the instrument with these. But I was still missing the middle-range of the instrument (G5 through B5). From here I started searching through secondhand stores and markets. I knew it was much less predictable of what kind of glasses they would have, but I was ready to sift through their stock to find the right ones. After spending hours in 3 different stores I found a few good glasses that fit the pitch range I was looking for (at the time of writing this blog, I’m still searching for more of the missing notes) and would be sufficient enough to build the basic set (minus the microtonal ones that I still need to find).

Once I collected all the glasses I could find, it was time to bring them together and start tuning them. I tune my glasses in Just Intonation, which allows for very pure and resonant intervals within the octave. For this I use a Peterson Strobe Tuner that was recommended to me by Ellen Fullman. As I add water to the glass the pitch will go lower. It’s best not to fill the glass up more than halfway with water, otherwise it gives a muffled, less resonant sound. If I add accidentally more water than I need, I use a turkey baster to take out small amounts of water until I’m exactly on the pitch I want. 

Once the glass is at the desired pitch, I mark the water level with an oil pencil. I repeat this method for each glass until I have every note of my scale.

Finally, I place the glasses in a strategic arrangement on a glass tabletop. Ideally, I want the glasses as close to each other as possible, in a melodic sequence, so that I can play as many of them at one time as possible.


Once the glasses are in the best order, I trace the outline of the base on the tabletop, add a special silicone to the bottom of each glass and permanently attach them to the tabletop. It takes about 5 days for the glasses to permanently adhere to the surface and be waterproof. 

Currently I’m still finding the missing pieces to fully build the instrument to the size and pitch-range that I want it, but I do have a set that is large enough to create the sounds that I need for my upcoming performances. Below is an image of the set that I used for Dohee Lee’s MAGO performance, and I will have a bit larger set for the November 21st L@TE performance at BAM/PFA.


I suppose the beauty of this instrument is that it is constantly growing and developing. I am always keeping an eye open for new glasses and am continually finding new techniques to play this amazing instrument.

Another video: