Tonbak Drum Skin Replacement
A Note on the Tonbak Skin Replacement
Introduction. Drum skins (drumheads) significantly impact the sound of your tonbak and the music you play. There are several factors to consider when choosing and changing drum skins. The main purpose of this note is to explain which skin to use and how to replace the tonbak's skin (in Persian, "ta'viz-e poust-e tonbak تعویض پوست تنبک").
A brief on the tonbak. The tonbak (also known as tombak, donbak, dombak, or zarb) is a Persian goblet-shaped drum and the chief percussion instrument of Persia. The tonbak consists of five parts: the skin, body, throat, small opening, and large opening. The skin of the tonbak covers the large opening and is secured to the edge of the drum using a traditional and natural glue called "serishom" (سِریشُم) in Persian.
A brief on the serishom. Serishom is a sticky substance obtained by boiling the bones, cartilage, and skin of animals such as cows and fish. It turns yellow or dark after drying and is used in carpentry to glue wood and boards. The use of "serishom" (سریشم) as a traditional Persian glue dates back centuries. For example, the Persian poet Nizami Ganjavi (c. 1141 - 1209) mentions the term serishom in his poems. Here is one of his verses that includes the term "serishom":
سبویی که سوراخ باشد نخست به موم و سریشم نگردد درست
How to replace the tonbak's skin
If the skin of the tonbak is damaged, it is necessary to replace it with a high-quality skin. Here is a step-by-step guide on how to replace the skin:
1. Wet the Skin: The part of the skin stuck to the body of the tonbak needs to be wetted using an appropriate amount of water based on the skin type. For example, if the tonbak's skin is camel skin, pour about half a centimeter of water into a large pan and place the tonbak upside down in the water, allowing the skin to become completely wet. After about an hour, the skin and the "serishom" glue between the skin and the wood will be moist enough to easily and smoothly separate the skin from the tonbak, using a screwdriver if necessary.
2. Alternative for Softer Skins: If the tonbak's skin is softer than camel skin, such as goat skin, it is not necessary to submerge the tonbak upside down in water, as too much water may damage the wooden body. Instead, wet the skin with a damp cloth and wait until it is safe to remove the skin.
3. Remove the Damaged Skin: Once the skin is sufficiently moist, carefully remove it from the tonbak.
4. Clean the Wooden Part: Use soft sandpaper to clean the wooden part of the tonbak where the skin was attached.
5. Apply Wet Serishom: Rub some "wet serishom" on the prepared wooden part to stick the new skin onto the body of the tonbak.
6. Stretch the New Skin: The tricky part is determining how tight to stretch the new skin around the large opening. If it is stretched too tight, the skin or even the body may break when it dries. If it is too loose, the skin will not sound properly and will need to be stretched again.
7. Fix the Skin: Once the skin is properly stretched around the large opening, fix it in place using eight small pins and a cloth rope. Ensure the pins are small enough not to damage the wooden body of the tonbak.
8. Remove Pins: After the skin has dried, remove the pins and the rope.
To find out what skin can be used for the tonbak, see my note The Skin and Wood of Persian Drums.
Also, check Structure of Tonbak.
References.
[N]: Peyman Nasehpour, Personal Interview with Ostad Nasser Farhangfar, Tehran, 1990.
[S]: Mehdi Setayeshgar, Vazhe-Name-ye-Musighi-ye-Iran Zamin, Tehran, Vol. I (1995) & Vol. II (1996).
[T]: Hossein Tehrani, Amouzesh-e-Tombak (Tombak Rudiment), Tehran, 1970.
Keywords. replacement, substitution, repairment, tonbak, tombak, donbak, dombak, zarb, drum, skin.