Some basic information about violin, viola & cello set-up for teachers and players - what you can do, what to watch for and what to leave alone.
(Notes from workshop given to AUSTA string teachers, November 2000)
PEGS: There is probably nothing more frustrating for a teacher than to spend half a lesson trying to tune a student's instrument. Badly fitting pegs can not only dampen the enthusiasm of the player, but they may also damage the instrument. Trying to force a peg to hold in place puts pressure onto the sides of the pegbox and this can cause a crack to occur, usually running along the grain between two of the pegholes, or to the edge of the pegbox.
To check how well pegs fit in the holes, remove the string from the peg and the peg from the pegbox. Examine the two worn areas on the peg shank where it contacts the sides of the pegbox - you should see two even shiny rings. The less the area of contact, the worse the fit and the more likely is the peg to slip.
You can try to improve the movement of the pegs by applying a peg paste (such as Hills Peg Paste) - this not only lubricates the action of the peg but it will also provide a slight "grip" to resist slipping. Or you could try using combinations of chalk and soap (in moderation). If the pegs still refuse to hold you will need to visit a violin repairer who may (reluctantly!) be able to file them to a better fit - otherwise they will need to be replaced.
The position of the string hole in the peg can also affect the ability of the peg to hold in place. Ideally the string hole should be positioned to allow one turn of the string inside (away from the pegbox wall), and all of the subsequent turns outside (between the string hole and pegbox wall). The final turn of the string should bring it just up against the wall of the pegbox, to provide a locking action which will resist the tendency of the peg to pull out. The string should not be crammed in tight as this will force the peg in further and may jam it altogether. It may be necessary to take a couple of turns on the outside of the string hole before crossing over. It is a very simple procedure for your repairer to drill a new string hole in the correct place.
Finally, students should always be encouraged to turn pegs with one finger and the thumb while the rest of the hand holds the scroll (as soon as their hands are big enough to cope). This tuning method tends to keep the peg in as it is turned, whereas the hand-off-the-scroll technique tends to pull the peg out and is more likely to result in a slipping peg. Also pegs will often pop with changes in humidity and temperature so it is a good idea to keep instruments in a closed case when not in use.
NUT: The distance between the top and bottom strings at the nut should have been accurately set, and the other strings placed evenly between. We use the following measurements for the total string spacing at the nut:
Violin: 16.5 mm (down to 12 mm for smaller sizes)
Viola: 17.5 mm (down to 16.5 mm for smaller sizes)
Cello: 23.5 mm (down to 20 mm for smaller sizes)
The height of the nut should be sufficient to give a visible clearance between the strings and the fingerboard. Also the strings need to leave the front edge of the nut cleanly to avoid the possibility of buzzes and other extraneous noises. The back edge of the nut should gradually fall away so that the strings do not change angle suddenly over an "edge" which may lead to breakages. All edges of the nut which will contact the hand should have been carefully rounded and smoothed.
Another consideration is the material from which the nut is made; ideally it should be a good quality ebony. Cheaper instruments often use a softer wood which cannot be polished to a smooth glassy surface and so the strings tend to "grab" as they are tuned. String grooves in softer woods will also rapidly wear and deepen, increasing the chances of catching a string. This is a very common problem on Chinese cellos. If you find that a string is continually breaking at the nut it is worth having it examined and possibly replaced. It costs around $100 to fit a new cello nut, about the same price as 3 Jargar A strings.
Also look at the depth of the string grooves. They need only be one third the diameter of the string. Keep a 2B pencil on hand to lubricate the string grooves every time you change or remove a string. It is a good policy to always pull strings up to pitch slowly, so that the tension has a chance to equalise on either side of the nut.
FINGERBOARD: The fingerboard needs to be shaped to a very complex series of curves for optimum performance. In addition to the obvious cross-sectional curve it is also slightly scooped from end to end, and this scoop increases from the treble to the bass side. The shape of the fingerboard needs to be graduated carefully so that there are no bumps which could give rise to buzzing strings. You can place a ruler lengthways on the fingerboard and view it from the side to see the extent of the scoop and whether there are any obvious bumps (cellists will need an extra long ruler).
Watch also for the longitudinal ruts which will wear under the strings over time. The fingerboard should be made from good quality ebony - cheaper instruments will have inferior (and therefore faster wearing) wood.
BRIDGE: Position - see separate bridge page.
The bridge should have been cut to a precise height, usually based on the distance between the very end of the fingerboard and the top and bottom strings (referred to as the "string heights"). There is no universally correct measurement - different repairers use different string heights, some taking their measurement from the middle of the string while others measure to the bottom. Also different types of strings may require different strings heights, and players will often have a personal preference for their string action. Finally it should be noted that your instrument is actually a subtle hygrometer and the string heights will vary with the humidity!
To check your string heights you will need a ruler with measurements that go right to the end. Sit the ruler perpendicularly on the end of the fingerboard so that the string passes across the scale and just read off the string height.
We generally use the following string heights for treble and bass strings:
Violin: 3.5 & 5.5 mm (down to 2.5 & 4.5 mm for smaller sizes)
Viola: 4.5 & 6.5 mm (down to 3.5 and 5.5 mm for smaller sizes)
Cello: 5.5 & 8.5 mm (down to 4.5 and 7.5 mm for smaller sizes)
The other important measurement on your instrument which relates to the string and bridge heights is the "elevation" of the neck, measured as the height of the line of the fingerboard at the bridge. If you place a ruler along the centre line of the finger board so that it projects beyond it and touches the bridge, then the distance from this point to the belly gives the elevation. In very general terms a low elevation means a low bridge height and a gentler, quieter sound with the possibility of the bow rubbing against the middle edges of the belly. A high elevation means a high bridge and a harsher, louder quality of sound. Note however that the relative effect of the bridge height may be balanced by some other aspects of the instrument's construction or set-up. In other words, don't worry too much about the elevation unless it's causing obvious problems.
The elevation also changes with humidity and this can be particularly noticeable on cellos (higher humidity = lower elevation = increased string heights). It should also be mentioned that if you happen to notice that your string heights are continually increasing while the elevation is dropping alarmingly then it may mean that the neck is falling out!
SOUNDPOST: The position of the soundpost is critical to the quality of the sound produced by your instrument - a shift of just one or two tenths of a millimetre can result in a discernable difference. Adjusting the position of your soundpost is most definitely a job for the experts. If it is not done properly and carefully it will almost certainly result in damage to the inside of the belly and at worst may cause a soundpost crack. So don't try it yourself and don't let any other amateur soundpost adjusters have a go at your instrument!
It is however a simple matter to make a soundpost gauge, so that you can measure and monitor the approximate position of the post. If your instrument sustains a knock or if the sound suddenly changes, you will then be able to check whether the sound post has been moved out of its position.
A soundpost gauge is a rectangular piece of cardboard or plastic with a cut running parallel to the sides and extending along most of the length. This simple device can tell you two important aspects of the soundpost position - how far it is behind the bridge, and how far it is inside the line of the bridge foot. It will not tell you the other three important aspects - how vertical the post is, how well it fits, and how tight it is.
When fitting a soundpost we usually begin by placing it at a distance of one half of the bridge foot thickness behind the bridge foot and from 1 mm (for violins) to 2 mm (for cellos) inside the line of the bridge foot. We then adjust it from this position to optimise the sound to suit the player's requirements. You can measure and note the current position of your soundpost and you might like to discuss the placement of the post with your violin repairer next time you visit.
TAILPIECE and TAILGUT: Tailpieces fall into two groups - wooden (usually requiring fine adjusters to be fitted), and metal/plastic with built-in adjusters. The main problem with the add-on adjusters is that they are a very common source of rattles. Check that the locking nuts of the adjusters are good and tight. Also note that these adjusters are really designed for use on the top one or two strings. Many people put four of them onto a tailpiece, then try and squash the bass strings into a gap that is too small. If you must use adjusters on all four strings you will need to open the gap with a small screwdriver to accommodate the thicker strings.
We usually recommend that if an instrument does require fine tuners on all four strings (either because of difficult pegs or inexperienced players) then it should have a tailpiece with built-in adjusters fitted. They are far simpler, lighter and less troublesome.
The small "on-the-string" tuners found on Chinese instruments are an abomination and should only be used for land-fill.
The modern synthetic tailguts with threaded ends and metal locking nuts are very reliable. The excess ends should have been cut off, otherwise they could touch the belly and buzz. We also melt and "blob" the ends just above the locking nut so there is no chance of it working off.
ENDPIN and SPIKE: Endpins occasionally break and more commonly pull out if they are too loose. Look at the endpin or spike from the side and check whether it seems secure. A small gap at the back is acceptable, but a larger gap is a matter of concern. You can improve the fit temporarily by packing out the hole with cigarette papers, ordinary paper or even a strip of sandpaper. Cheap spikes on cellos can be another source of endless irritation for teachers and students. The locking screws strip their threads and can't be tightened effectively and the spike rattles and slips. The only remedy is to have a new spike fitted, but be aware that if the hole is too big it may need to be bushed.
STRINGS: When choosing strings you can really only use the trial and error approach to try and find a combination that suits you, your instrument and your bank balance. Keep in mind that the price versus sound relationship is an exponential curve, so at the cheaper end of the scale a small price difference (say $10 - $20) can mean a huge increase in quality. Generally we find Piranitos are adequate for the smaller student violins, while for 3/4 to full size we would start with Dominants.
Every time you break a string (or if a student's instrument is regularly breaking strings) make a note of where it occurred. If the breakage is regularly happening in the same place it may be caused by some aspect of the instrument, such as a sharp edge on an adjuster, an inferior nut or a problem at the bridge.
© Alan Coggins 2002