Duck hunters are born searching for an edge, just something a little different that will put more birds in the bag.

They create and test, adjusting existing products and dreaming up new ones to unlock the key to consistent success in the fields and woods. Hunters are sure that full limits are just around the corner if they can only find a way to fool the wary nature of pressured ducks.

Some ideas work for a while, some never at all, and some are so good that they stand the test of time.

Phillip Olt lived in Pekin, Ill., near the Mississippi River and saw a need for commercially produced duck and goose calls that could be sold to local hunters for profit. He converted a chicken coop on his farm and started making calls by hand in the late 1800s and by 1904 the P.S. Olt Game Call Company was open for business.

The company closed its doors in 2002 but it made its mark in many ways during 98 years of developing calls to lure wild game into gun range. While Olt made many calls, his legacy lies in a simple duck call he named the D-2.

Separate the insert from the barrel on a modern call and one can see the genius of Olt. He placed a straight reed shaped like the tongue of a mallard hen above a curved tone board, thus focusing the sound out the end through an open hole. The resulting quacks that came out of the call sounded like a hen looking for company and it became one of the essential tools in every serious duck hunter’s arsenal.

By the 1950’s, the D-2 could be found on lanyards all across the country.

David Jackson worked for Olt for nearly 30 years and had a hand in manufacturing thousands of D-2’s. His company, DJ Illinois River Valley Calls, still produces the D-2 in several polycarbonate variations including the Arkansas Cutdown model. Frequently, this style of call is seen with the insert turned around and placed in the rear of the barrel. This came from necessity more than personal preference.

“All of the early D-2 calls were made from compressed hard rubber,” Jackson said when asked about this modification. “Over time, hard rubber will lose its compression and the insert will loosen from the barrel. Since the D-2 has a straight barrel, it is easy to just turn it around and place it in the other end.”

Hard rubber was the earliest form of man-made plastic used in the industrial era with the main difference between it and regular rubber being the sulphur content. Hard rubber was first produced in the 1850s and many color variations were tried but only black would withstand abuse, all other colors proved to be too brittle.

“Up until 1939, the call had a round hole in the end,” Jackson said, continuing the D-2’s early history. “Most people are too young to remember this and think that the round hole did not come along until a manufacturing change in 1956. The popular keyhole or keyway calls were made with the deeper slot in 1941, the result of an effort to remove the core pin easier without distorting the molded part.”

Jackson said modification of the D-2 began early in production.

“Hunters around Grafton and Quincy, Illinois, started changing the tone boards to achieve a different sound,” he said. “It is widely thought that this didn’t start until the 1950s and 60s with guys such as Lester Capps down South, but it was much earlier than that, around 1910 in that part of the country.”

Two of the biggest states in terms of days hunted by a population and number of ducks harvested every year are Arkansas and Louisiana, so it didn’t take the D-2 long to find its way down the river into the region.

There too, hunters started modifying their calls to suit their styles of hunting. Arkansas required a louder and deeper tone to reach through the green timber and a raspier bark was preferred for the marshes of Cajun country.

The main difference in the modification is the sharper cut on the tone board of the Louisiana style with more reed hanging over the board to create more rasp in the quack.

For many years the Olt D-2 was a guarded secret of the best duck hunters, especially in Arkansas’ famed public woods. But the information age changed all of that.

On Internet message boards hunters started asking others about modifying the calls themselves or who could do it for them and many started taking notice. A cottage industry in call modification sprung up and the original calls, especially the keyhole models, became high in demand.

People started buying up all the old calls they could find so a market for new calls with that signature sound was created. Now smaller call makers and the bigger names have jumped into the fray with new models aimed at capturing a piece of this market.

Jim Ronquest of Rich-N-Tone calls in Stuttgart, started hunting with a D-2 as a young boy, learning the skills that would make him a future World Champion caller.

“My very first call was a D-2,” Ronquest said. “The guys I grew up hunting with had modified their D-2s and it wasn’t long before I was experimenting with mine. We all wanted to achieve that deep sound of an old hen that we heard in the flooded woods along with having the volume to reach high ducks and retain that realistic old hen sound.

“I actually ruined a few calls before I hit on the sound I was looking for.”

Ronquest said he thinks the call’s effectiveness may lie in the lower sound range that seems to carry farther in the air.

“I used to live in a house near Holly Grove, Arkansas, that was about a half-mile or so from a buckbrush slough. It would load up with mallards from time to time and in the winter my place was generally always upwind of them. I could still hear those old hens firing off, even with the wind at my back. That bass sound just carried across the field to me.”

Cutting down an Olt tone board means different things to different people. Ronquest clarified the process.

“Some guys like to cut down the end of the tone board at about a 45-degree angle with the reed overhanging the insert,” he said. “Others will file and sand to re-shape the tone board to reach the desired sound and volume. Some are clean some are raspy but what we are all looking for is that deep rattle at the finish of a sequence along with the big volume almost a bark on top. That seems to make the difference in turning ducks toward your spread or breaking high ducks hunting public woods.

“Up close in a room these calls blown hard may not sound good to most folks, but get out in the woods just a little ways and it is a whole different story. Every creature has a voice designed for their environment. The pintail hen has a high pitched whistle because she stays on the open prairie, the mallard hen needs a deeper voice to be heard where she lives.”

Rich-N-Tone recently started manufacturing its version of the Cutdown D-2, called the DC Mondo. “Mondo” is a slang term meaning “enormous” or “huge,” as in numbers of ducks coming to the call.

Ronquest described the call as having the volume of an Olt with the finesse of a Rich-N-Tone.

Bill Cooksey of Avery Outdoors has spent his share of time hunting ducks in different venues around the country. He agrees with Ronquest that a deeper sound carries farther.

“I think a lot of it has to do with the sound frequency,” he said. “A modified Olt D-2 has a lower pitch than a standard call and I think it carries better in any conditions. Whether you are in timber, fields or open water, ducks seem to hear that deeper sound easier.”

One of the first call makers to replicate the cutdown D-2’s is Black Ops Calls based in Benton.

Black Ops started producing calls in December, 2009, but the idea behind the call came well before that.

Mike Fleeman, of Black Ops, recalls the first spark of an idea for what became their product.

“I was sitting around the duck camp with a buddy who has just received two original D-2 calls from a seller on eBay,” Fleeman said.

“They were not in the best condition and I said jokingly that it would be great if you could buy a new call that could be used right out of the box without modification. Well, we put some more serious thought to it and decided to make the call we wanted and offer it to the public.”

Fleeman explained the difference in a Black Ops call versus other models.

“We wanted to make a call out of as close to the same material as the original keyhole calls as we could,” he said.

“We achieved that and decided to make them in white instead of black to distinguish our call from the original. I took the first prototype hunting with me in 2008 and soon people were asking me where they could get a white D-2.”

Fads in waterfowl hunting come and go; only the best inventions stand the test of time. The D-2 and its many variations are alive and well because they work.