Summary: Being able to sound like multiple ducks on the water can be a huge benefit on some days. By changing up your cadence, tone, tempo or volume you can get your duck call to sound like different or multiple ducks.
An Important Note - Your ability to produce the multiple sounds a hen mallard makes will either be enhanced or diminished by the range of sounds your duck call can produce. If you are blowing a duck call that only produces sounds from 4 to 7 on a scale of 1 to 10 you will be severely limited in your ability to produce the multiple sounds a hen mallard makes, regardless of your call skill and ability.
When we refer to cadence we are referring to both the calling sequence you are blowing (i.e. the greeting call or the comeback call) and the number of notes you use to blow the sequence. First, in order to sound like a duck and not a duck caller, you need to understand how and when to properly use different calls within your calling sequence. Different calls within your calling sequence are needed as you work ducks closer and closer into your decoy spread.
Second, by varying the amount of notes you use to blow the same calling sequence; you can create, in a very simple way, the illusion of different ducks calling. For example, if your typical greeting call consists of seven notes, scale down to five than up to eight than down to four notes to produce the sound of different ducks using the same calling sequence.
Tone is the sound that is produced from your duck call. The ability to produce multiple sounds or tones from your duck call is what separates the outstanding duck caller from the average and ordinary duck caller. Varying your tone allows you to produce high-pitched sounds, low guttural sounds or whining pleading sounds from the same call. Varying your tone can be accomplished through the use of backpressure, hand position, finger position and movement, and through the amount of air and air pressure being blown into the call.
A duck caller who has mastered the ability to vary the tone of his call can go from a high pitch to a low pitch back to a high pitch and end up with a whining pitch using only one breath of air. They accomplish this task by using the various means described above.
When referring to tempo we are referring to the speed at which blow your cadence. For example, by varying the speed and the emphasizing different notes, you can use the same calling sequence and sound like four or five different ducks. Take the greeting call, just by varying the speed of your greeting call you can sound like a very excited duck, a contented duck, a lazy duck or a concerned duck. You can do the same thing with the feeder call, the quack, the comeback call as well as the lonesome hen and hail call.
The best way to understand how to use tempo is to realize that you can say the same words (i.e. "Greg, I need your help") but at different speeds and with a different emphasis on a word or words and the same sentence can have a totally different meaning.
And finally, you can vary the volume of your calling sequence to give the illusion of many different ducks calling within your decoy spread. Since not all ducks call at the same volume, neither should you. In fact, one of the keys to reading birds is to understand the amount of volume they are comfortable hearing.
As with tone, you can control volume through the use of backpressure, hand position (an open hand for more volume and a closed hand your quieter volume), finger position and movement, and through the amount of air and air pressure being blown into the call.
Practice varying your cadence, tone, tempo and volume and once you start to get the hang of it, get a tape recorder and tape yourself. You'll be amazed at how many different sounds you can produce and how many different ducks you can sound like using the same call.