Understanding viola size

The size of a viola is usually given as the length of back measured over the arching from the side of the button to the centre line at the bottom. Violas of between 16 and 16 ½ inches [40.6 to 42 cm] are considered as medium size, with small violas sometimes being as short as 15 inches, [38.2 cm] with large violas occasionally reaching 18 inches. [45.7 cm] Although the back length probably is the most important criteria, there are other variables which have a great bearing on how big an instrument feels.

From a playing point of view, the main manifestation of viola size is how far you have to extend your left arm in order to play in first position. To get an idea of the importance of the left arm extension, without holding a viola, if you lift your hand so your fingertips touch your shoulder, and then very slowly move your hand away from your body, you will notice that once the upper arm moves past the vertical position the tension in your biceps starts to increase, most noticeably when the upper arm is around 45 degrees to the vertical. This is region where you need to hold your arm to play the viola. Although you might not be aware of it, there is also an increase in tension in your shoulder and back. If you then twist your hand round and pretend you are playing a violin [if you can bear the idea!] and then move your hand away and pretend to play a viola, as your arm extends further from your body you will also notice that it becomes more difficult to move your fingers. This combination of factors is why viola size is so important.

It’s not just the back length that’s important
However, just using the back length does not tell you how far you are going to have to extend your left arm; it is the combination of the body length and the neck length. You might think that there would be a standard length for viola necks, but that is not the case. Unlike the violin, viola necks are neither a standard length nor are they consistently proportional to the body, and the different models vary so much that you can, for instance, have a 15 ½ “ viola with a longer string length than a 16 ¼ “  viola, whereas two instruments theoretically of the same size [having the same length of back] may have necks that differ in length by 10 mm.

To see why this is the case, and the effect it has on playing comfort, let us consider two models of viola.

Andrea Guarneri











The first is an Andrea Guarneri model which has a back length of 16 1/4”, the other a Maggini model which also has a back length of 16 1/4”.  If you look at the Andrea Guarneri, the position of the bridge, the f holes and the c bouts are relatively low on the instrument, the proportions being typical of instruments produced in Cremona and Venice. The relatively low position of the bridge means that the part of the strings overlying the belly is relatively long. The decision the viola maker then has to make is to decide how long the neck should be. If this was a violin it would be simple; the neck length compared with the body stop [the distance from the bridge position to the edge of the belly next to the neck] is always in the ratio of 2 : 3. With a viola it is quite possible to do the same thing, and some instrument makers do in fact use the 2 :3 proportion, so in this case the neck would end up at 148 mm. But when I make this model I always use a neck length of 140 mm, violin makers allowing themselves to vary the neck length/body stop ratio on violas from 2 : 3  to 2 : 3.2 . The reason I use a shorter neck length is because the extension of the left arm is that much less, so the same ‘size’ viola feels smaller and more comfortable.

With the Maggini model however, the position of the bridge, f holes and C bouts is significantly higher up the instrument, typical of instruments made in Brescia. This means the body stop [the distance from the bridge to the belly edge next to the neck] is significantly shorter than on the Andrea Guarneri. If I was to make the neck the same length as the Andrea Guarneri, the overall string length would be rather short. One effect of a short string length is that the strings are at a lower tension when tuned to the correct pitch, and therefore the downwards pressure on the bridge is also lower. Although viola strings do work at a range of lengths, there is a range beyond which the strings are working outside their ideal parameters. So with the Maggini model I increase the neck length to 148mm. Nonetheless the overall string length is still shorter on this model than on the Andrea Guarneri.

Which is more comfortable?

So the question for the viola player is which instrument is more comfortable, the Andrea Guarneri model or the Maggini? For the left arm, the Andrea Guarneri requires less extension, and because the bridge is also nearer your body the bow arm is also nearer your body, which is also makes it easier to play. The Maggini model however, does have a shorter string length so your fingers are closer together. So if you have relatively short fingers and long arms this model would perhaps suit you. Otherwise for most people, the Andrea Guarneri model would be easier and more comfortable to play.

Why then, would anyone choose to make or play a Maggini model? The answer is in the sound, the Brescian models such as Maggini tending to have a different quality of sound, more reedy, somewhat broader and less sweet. Within the wide range of viola sound, some viola players prefer this sound, and if you are big enough to play it comfortably, that is fine.

Ultimately it is for each individual player to balance the sound they want to produce with an instrument that is comfortable to play. At one time it used to be said that to get a good viola sound required a big instrument, but improvements, particularly in string technology, have largely changed that perception. It is also the case that many older small violas weren’t much good. Inevitably these factors led to many violists to play instruments that were too big for them, often causing back, shoulder and arm problems.

Nonetheless, it is easier to make a viola which sounds good if it is over 16 inches long, particularly in respect of the C string, which is one reason why there is greater choice amongst instruments of this size.  However, just because it is hard to make a good sounding small viola, that doesn’t mean it is impossible, and there are a number of violin makers with a particular interest in violas who consistently produce good small instruments. So if you think you need a smaller viola but haven’t found one which suits you, you need to carry on looking.

Three things you need to know

If you are thinking about getting a new viola, as far as size is concerned, there are three things you need to know about your present instrument and any you hope to try. These are the back length, the neck length and the open string length, with the body stop measurement as an optional extra. Adding the back length and neck length together will tell you how far you will need to extend your left arm. From this measurement, if you subtract the string length you will know how much your right arm will be extended, and the open string length will of course indicate how far apart your fingers will need to be.

Although these measurements will help you compare instruments and to understand why they feel different, what they do not tell you is whether the instrument is heavy, whether it has an uncomfortable neck, how easily it responds, or of course what it sounds like. To find those things out you will have to play it.

William Castle is a professional instrument maker from Shropshire who specialises in small and medium size violas. He has also made a video on viola size which is available on U tube and on his web site – www. williamcastle.co.uk