HMGCC engineers have been working with a limbless dummy with a small speaker where the mouth should be to simulate human speech. Realistic speech quality is a very important criterion for this project, and one of the many uses of Helix is to EQ the mouth speaker. "I particularly appreciate the rich functionality of Helix, which has allowed the replacement of several EQ units and laboratory audio filters with just one box," says Ken Worrall. "The ability to control both channels independently is an extremely useful function, as is the option of controlling it from a PC in addition to the front panel. The DN9340 is a very precise, affordable alternative to some of the measurement equipment on the market."
Other of HMGCC's uses of the Helix include providing an equalisation correction for the in-ear to free field transfer function, used in calibrating headphones during the measurement of the noise exposure of headphone users.
(Lee Baldock)
