By Wade Bourne

A duck call is a bona fide musical instrument - specifically, a woodwind. Sound is created by blowing air across a vibrating reed. A skilled duck call 'player' can produce notes of differing length, pitch and volume to simulate calls made by the birds. Truly, a good caller is a talented musician by any measure.

But to make quality sounds, a duck call must be properly tuned. It must be set to the caller's air pressure and style of blowing so it will effortlessly produce a full range of high to low notes. In contrast, an improperly tuned call will present an ongoing struggle to make the right sounds. The following tuning tips from two experts in the game call business, Bubba McPhearson of Primos Hunting Calls and Rod Haydel of Haydel's Game Calls, will help keep your duck calls in top working order.

Single-reed calls

'There are really just two things to do to tune a single-reed call,' McPhearson begins. 'First, you can shorten the reed. Most duck call reeds are made of Mylar, and you can trim them to produce a higher pitch. Take the call apart, remove the reed and cut off a sliver with a pair of fine scissors.

'But you don't want to cut off too much,' McPhearson warns. 'You want to take off only four to five thousandths of an inch at a time. This is barely enough to see that you're trimming it. Then reassemble the call and blow it to see if you like the sound. If you want the call even higher pitched, cut off a little more and try it again.' McPhearson says shortening the reed actually makes a call easier to blow, but removing too much reed also reduces volume.

The other tuning adjustment hunters can make on a single-reed call is sanding the tone board, which is the stopper piece the reed rests on. 'Sanding adds texture to the tone board's surface, and this makes the call raspy,' McPhearson continues. 'You don't want to get too aggressive with the sanding. Use 220-grade paper or finer, and sand the tone board lightly. You don't want to remove any material, just rough it up a little.'

In a single-reed call, a cork wedge holds the reed in place, and after long use, the wedge may harden and fail to hold the reed tightly. 'If the reed starts slipping, you may need to replace the cork,' McPhearson advises. He says most manufacturers offer replacement wedges and reeds through their customer service departments.

Double-reed calls

Tuning a double-reed call is more involved, according to Rod Haydel. 'There are more movable parts: two reeds, the wedge (usually hard plastic in a double-reed call) and the tone board,' he says. 'Moving any combination of these parts will alter the tune of the call.'

Haydel says before tuning a double-reed call, a hunter should note how these parts are positioned relative to one another. This is the starting point for making adjustments. 'You should take a fine-point Sharpie and mark how all the parts line up with one another,' he says. 'This gives you something to measure adjustments against.'

Haydel says most changes in a double-reed call are made by moving the wedge backward or forward on the tone board. 'Leave the reeds where they are, and slide the wedge back (away from the reeds' tips) to lower the pitch; slide it forward to raise the pitch,' he instructs.

Haydel says if a double-reed call is hard to blow, the reeds can be trimmed very slightly or simply pushed back toward the end of the call. 'This adjustment may also raise the pitch and create an unbalanced call that won't produce a full range of notes,' he adds. 'To compensate, you may need to push the wedge back slightly to lower the pitch to a comfortable, balanced level.'

To add rasp to a double-reed call, Haydel says you should offset the reeds so the tip of the top reed is pushed back 1/16 to 1/32 inch from the tip of the bottom reed. 'When tuning any call, always make very slight changes and then reassemble the call and test it,' Haydel advises. 'It doesn't take much of a change to make a big difference in a call's sound.'