My son plays the violin. Recently, we saw that someone in the neighborhood is selling a viola, I don't remember the exact size, perhaps it was 1/4. Is it possible to string the viola using violin strings and to play it as a violin?
I know that an adult-sized viola is larger than an adult-sized violin, but are there any differences in the dimensions of a violin and a viola, so that maybe a 1/8 sized viola is equivalent to a say 1/4 sized violin?
Yes, it is absolutely possible to restring a smaller size Viola into a Violin. You will not damage the instrument by doing so.
Fractional size violins can roughly correspond with smaller size violas, although technically some will be slightly different in length.
In most cases if the strings are good you can move the G D and A strings down and add a new E string.
The tension of viola strings run slightly higher than violin strings, so keeping them may be similar to moving to a higher tension violin set, although looking at a string tension chart there is some pretty wide variation of tensions by brand across the smaller size instruments.
Technically the body of the viola is usually deeper than a violin, but in some brands I've seen the only difference between the viola and violin models was the label inside, and what set of strings were put on. The dimensions were otherwise identical.
I haven't personally made a viola, but checking my measurement book it looks like the full size viola top plate is made slightly thicker. For mass manufactured student size instruments I seriously doubt that most models would have a different tooling than the violin plates.
Another difference you may see is the viola bridge can be set slightly higher than a violin bridge would be, up to a millimeter or so for the thicker strings.
If the viola you are converting does have a deeper body or thicker plates, there will be a tonal difference. In the mass manufactured student instrument market it is unlikely that the tonal difference will be significant.
If you have a hand made and plate-tuned smaller viola made by a trained Luthier, then I wouldn't recommend converting it, since it will have been made to respond to the viola tuning and it is better to keep that kind of instrument in the tuning it was designed for.
I would not recommend it. Full size violins and violas have significantly different lengths, so you may end up in something with a similar length, but:
So you would have to restring the instrument, risk damage due to higher tension and it is not guaranteed, that it sounds well afterwards.
Given, that viola players are typically in short supply in amateur orchestras (quite the opposite with violin players), your son could switch to viola, however. The teacher of our son regularly let her students try playing the viola - it's always possibly, that the student finds it more pleasing. The need to learn the alto clef is a disadvantage, however, even if some casual players use mental short cuts to map the score to treble key.
I transitioned from violin to viola by playing a 3/4 size viola for a while. While the 3/4 viola (a Boosey and Hawkes, from memory) was nominally the same scale length as a 4/4 violin, the body was notably deeper.
It's not an absolutely terrible idea, functionally speaking (14" viola = approx. 4/4 violin), but do keep in mind that this is mostly preferable for fractional instrument sizing.
Adult full size violas are much larger (most professionals play 16" or larger, a few play 15.5", and even fewer play 15"). Just be sure to use proper viola strings (you might need to have a viola bridge carved to accommodate the strings properly), and also be aware that the body of the violin is meant to resonate best at its intended frequencies, so the body is thinner than your average viola proportions and may not be as resonant especially in the lower frequencies.
In essence, it functionally works, but ends up being a sub-par instrument.
Regardless of the size of the viola or violin they operate in different registrars. If you play violin for music written for viola you will find a whole lot of notes impossible to play. The lowest notes on a Viola is the c an octave below middle c where the violin only goes as low as the g below middle c.
Also even if you have music that fits the compass you may know also find that the fingering is all wrong and this may make music again either impossible or a whole lot harder than need be. This may be the case regardless of the size of the particular instrument
