For a musical instrument to be playable, it needs to fit the human body and hands, which is called ergonomics. However, ergonomics is also not a 'one size fits all' problem, as everyone's hands are different. Knowing the factors which affect an ocarina's ergonomic behaviour will allow you to better evaluate instruments, and find ones which work better for you.
The first part addresses the design of single chambers, and the second part extends this with additional details for multichambers.
Single chamber ocarinas
Body shape and support points
The shape of an ocarina's body is very important for ergonomics as it must be comfortable to hold. It must also provide areas for you to support the instrument while playing the high notes.
Both the right pinky finger and left index finger are used to support an ocarina while playing the high notes, and the design of an ocarina's must provide adequate space for both of these fingers to rest besides their finger holes, to be ergonomic.
The overall shape of the body also matters, as it is important that the instrument provides a way for the player to hold it, without feeling that their fingers are sliding off the instrument. Due to this, ocarinas should not be excessively 'egg shaped' as this does not offer the player good instrument support.
The two diagrams below contrast a good and bad design. In the good design:
- A notable space is left besides the right and leftmost holes, shown by the vertical lines.
- The right and left hand sections of the body are pretty straight to prevent fingers sliding off the end of the body.
Contrast this with the bad design:
- The chamber is very rounded with the holes butted right up against the end of the chamber.
- There is nowhere to rest the pinky to support the instrument.
- The rounded shape encourages fingers to slide off the body.
Consequently, such designs feel unstable in the hand.
It should also be noted that features added for visual effect often work against playability. For example:
- Placing a protrusion on the inside of the tail may look good, but can get in the way. There is a technique called the palm grip, and if this is done on such an ocarina, the protrusion will dig into your hand.
- Curved chambers can also look good but cause numerous problems; if the body curls away from the mouthpiece as shown. The left hand must turn inwards more than normal to counteract the curve. The overlaid lines show the average angles of the two hands.
The opposite of the second design, with the chamber curling toward the player, is even worse as the right hand is scrunched very close to the face and the curve encourages support fingers to slide off the end of the body.
How the ocarina is balanced
Balance also has a very large impact on the ergonomics of an ocarina. It is especially important with single chambers as they have two thumb holes, and correct balance is required for the player to easily open them. A poorly balanced instrument will also feel a lot heavier than a well balanced one—at best, making your job harder and, at worst, causing hand or wrist pain.
Ocarinas have two planes of balance, primary and secondary. The primary plane runs between the right thumb hole and the right tail of the ocarina. It allows you to support the instrument using only the right thumb and pinky when held parallel to the ground.
The secondary plane runs between the left pinky hole and the mouthpiece. It is less important, being used in combination with the primary and rarely, if ever, by itself. Note that this plane can only be used when the pinky hole is placed on the side of the instrument.
Poorly balanced ocarinas will fail to balance on one or both of these planes. Of the two, the primary plane is absolutely essential, and an ocarina with no primary balance will be very difficult to play. In absence of it, many more fingers must be used to support the ocarina, preventing them from serving their normal function.
There are two things to consider when evaluating an ocarina's primary balance plane: how the ocarina is balanced left to right, and how it balances front to back.
Left to right, an ocarina should balance between the right thumb and pinky, with a slight upward force on the pinky, when the instrument is parallel to the ground. If the ocarina falls away from the right pinky when you try to do this, you have a bad instrument. Conversely, if you feel an excessive amount of force pushing up on the right pinky, this is also poor balance and may lead to hand pain.
Front to back, the ocarina should either balance perfectly or have a slight tendency to roll toward the mouthpiece. Any ocarina which rolls forward is a bad instrument and will be exceptionally difficult to play. Working around this demands that more fingers support the instrument, as noted previously.
If an ocarina feels very heavy in your hand, try to find the instruments canter of balance. It should be positioned just to the left of the right thumb hole. If the thumb hole is positioned too far to the right, it will increase the pressure on the right thumb.
Hole placement and size
Hole placement is a somewhat difficult topic to discuss, as everyone's hands are different. Thus, what works for one player may not for another. The main point to note is that an ocarina's hole placement should allow you to hold the instrument comfortably, with gently curved fingers and straight wrists.
Kinking the wrists in perticular will tend to cause wrist pain, and can cause repetitive strain injury. The fingers are controlled by muscles in the forearm through a number of long tendons. These run through a small channel in the wrist, and folding the wrist hard in either direction compresses it.
For my own hands, keeping the wrist straight entails having my fingertips directly above my thumb, evident from the pictures. But as everyone's hands are different, this may or may not work for you. You can get an idea of the relative lengths of your fingers if you hold your hand like in the pictures, with the wrist straight and your thumb as horizontal as possible. Keep a slight curl along your fingers and note where the fingertips are relative to your thumb. Notice that the angle of your palm relative to the thumb and the angle of your forearm also matter.
While ocarina makers rarely document the hole alignment of their instrument, you can learn to recognise it from photographs. For example, a design which places the right hand finger holes very close to the edge of the chamber would work if you happen to have a long thumb relative to your fingers, but would force the wrist to fold if you don't.
You may be able to adapt to a hole placement that is not ideal for your hands if you allow your fingers to overhang the holes. 10 hole ocarinas are in theory better able to adapt to differences in players' hands, as there is no need to hold fingers back to avoid covering subholes unintentionally.
Hole placement is frequently one of the biggest compromises made in sculptural ocarinas, as the design is often made first and the holes placed to fit around it, not the player's hands. This often forces the hands to make awkward compensations like folding the wrists back and may cause hand pain as a result.
Because general playing technique requires sliding fingers over the surface of the instrument, surface finish has a big impact on playability. Ocarinas are commonly available with 4 different finishes: fired glazes, natural shellac, synthetic finishes, or the plain finish of the ceramic itself.
Very smooth and shiny finishes can pose problems as they trap moisture, which can cause your skin to cling to the surface if you have any moisture on your fingers. That problem does not exist with plain finish ocarinas as the earthenware is porous and absorbs finger moisture. It is also far less of a problem with rougher 'matte' glazes and shellac.
Finishes which are excessively textured, often for sculptural effect, can also be a problem. Unlike texture on a microscopic scale, this will frequently physically block the fingers from sliding over the surface, unless an ocarina is designed such that the areas around its finger holes are left smooth.
You can sometimes find inline ocarinas which follow the same fingering system as transverses, but with the mouthpiece on the end of the chamber, resembling a tubular instrument but shorter and wider.
While the fingering system is similar, it is worth noting that the ergonomics of inline ocarinas differ from transverse ocarinas. They retain two thumb holes, but due to their design, only have a single balance plane directly down the canter of the instrument, and the support points described above are thus ineffective.
Supporting inline ocarinas on the high notes is often achieved by pressing the pinky finger against the end of the instrument, balancing it between the pinky and the lips. For this to work, the end of the instrument needs to be shaped appropriately, and very rounded designs will be very hard to support.
Most multichambered ocarinas are a direct extension of the single chambered transverse design. Their fingering system is almost identical, but additional chambers are added to extend the range. The ergonomic considerations with multichamber ocarinas are mostly the same as with single chambers, but the following should be noted:
Like a single chamber, how a multichamber balances has a big impact on its playability. It is very useful to retain the ability to balance the instrument between the right thumb and pinky. As most multichambers lack a right thumb hole, this makes the instrument effortless to support.
Not all multichambers can balance like this however, as adding additional chambers tends to shift the centre of balance away from the player. Making them balance well requires using the mouthpiece and higher chambers as a counterweight. It is not easy to say if any given ocarina can balance like this without being able to hold it, unless you can find someone who already has one.
The shape of the mouthpiece
Each chamber of a multichambered ocarina has its own windway and typically only one is blown at a time. The air is directed into the desired windway by forming an aperture between your lips. As the interior of the lips are rounded, it is easiest to do this when the mouthpiece is also rounded in a complementary way. However, it is not uncommon to see multichambers with the mouthpiece coming to a sharp rectangular edge. This isn't very ergonomic, and will dig into your lips.