Ford is equipping the Focus ST with what it calls an “active sound symposer,” meant to transmit just the right engine sounds into the cockpit, under just the right conditions. Don’t think of this as a low-buck sound-tube, as used on the Ford Mustang, certain Volkswagen GTI models and the new Hyundai Genesis Coupe, either.
The problem with sound tubes is that they can transmit too much droning noise at highway speeds, since they’re generally not very sophisticated. The sound symposer used on the Focus ST, on the other hand, uses valving and a composite “paddle” to amplify and transmit the desired sounds only at the desired ranges.
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