A cox box is an electronic device used in competitive

rowing Rowing is the act of propelling a human-powered watercraft using the sweeping motions of oars to displace water and generate reactional propulsion. Rowing is functionally similar to paddling, but rowing requires oars to be mechanically a ...

that combines a digital stroke rate monitor, stopwatch, and voice amplifier. It is generally used by a

coxswain The coxswain ( or ) is the person in charge of a boat, particularly its navigation and steering. The etymology of the word gives a literal meaning of "boat servant" since it comes from ''cock'', referring to the wiktionary:cockboat, cockboat, a ...

to monitor the crew's performance, and amplify instructions given by the cox using a microphone and series of wired

loudspeakers A loudspeaker (commonly referred to as a speaker or, more fully, a speaker system) is a combination of one or more speaker drivers, an enclosure, and electrical connections (possibly including a crossover network). The speaker driver is an ...

. Although the term "cox box" is often used as a generic descriptor of this type of device, multiple companies have registered trademarks of similar terms. For instance, Cox-Box, CoxBox, and Cox Box are all registered trademarks of Nielsen-Kellerman.

Use

Cox boxes are mainly used in eights and fours rowing, where the readouts are used by the

to monitor the performance of the crew and manage the race. This is of particular importance in time trial races where crews race astern (as opposed to side-by-side) and so the performance of other crews cannot be easily gauged. It is also critical to assisting the coxswain in sticking to the race plan, which usually involves strategic changes of stroke rate (the number of strokes executed per minute by a crew.). The amplifier is linked to one or more

inside the boat, making it easier for the crew to hear commands. This is particularly important for rowers towards the opposite end of the boat, or the entire crew in windy conditions. The coxswain typically wears a headband-mounted microphone. Some units have a

walkie-talkie A walkie-talkie, more formally known as a handheld transceiver, HT, or handheld radio, is a hand-held, portable, two-way radio transceiver. Its development during the Second World War has been variously credited to Donald Hings, radio engineer A ...

connection to the coach, allowing direct communication with the crew. Rowing shells fitted with speed measuring impellers or GPS can report boat speed to the amplifier display, typically measured in m/s or 500 m predicted split time.

Stroke rate

Almost all modern coxswain's amplifier systems have a

liquid crystal display A liquid-crystal display (LCD) is a flat-panel display or other Electro-optic modulator, electronically modulated optical device that uses the light-modulating properties of liquid crystals combined with polarizers to display information. Liq ...

, showing the stroke rate. On most systems, a magnet is positioned under the stroke rower's seat. In bowloaders, the magnet is placed under the bow rower's seat. As the rower moves up the slide (moving forward to prepare for the next stroke), a measurement is taken and fed to the system. Additionally, the display usually features a timer that can be stopped, cleared, and reset, along with a stroke counter. The display is often equipped with a backlight, useful in poor lighting.

History

Before the development of the cox box, a commonly documented practice was to use a

megaphone A megaphone, speaking trumpet, bullhorn, blowhorn, or loudhailer is usually a portable or hand-held, cone-shaped horn (acoustic), acoustic horn used to amplifier, amplify a person's voice or other sounds and direct it in a given direction. ...

to improve audibility, strapped to the head of the coxswain. At the same time, the coxswain would use an analog stopwatch and rate watch, which was often cumbersome during races.

References

{{DEFAULTSORT:Cox Box Rowing equipment Coxswains (rowing)