Technical Overview
TWIN LF DRIVERS
Two identical 8”/8Ω aluminium-alloy diaphragm LF drivers deliver a -3 dB point of 20 Hz with a usable response down to 15 Hz at -6 dB. These units are user-replaceable.
CLOSED-LOOP LF CONTROL
To obtain the ultimate in low frequency response for the cabinet size, closed-loop feedback is used to control the LF drivers. This system uses an accelerometer mounted on each diaphragm. These feed motion-related signals back to circuits that ensure each 500 W power amplifier produces exactly the right drive current under all conditions, resulting in a highly accurate and extended low frequency response.
3-K DRIVER ARRAY TECHNOLOGY
An innovative positioning technique is used on the 328A whereby the midrange, tweeter and super-tweeter drivers are mounted on the 3-K driver array (patent applied for) in front of an acoustically-shaped reflection cavity extending below the baffle plane. This provides unmatched signal reproduction accuracy in the mid and high frequency ranges, together with excellent stereo imaging and dispersion. The 3-K driver array is user-replaceable as a unit.
AMPLIFIERS AND POWER SUPPLIES
All five amplifiers are conservatively rated for delivering sufficient power to the drivers to achieve the rated maximum acoustic output. The power supply high voltage rails track the average output for maximum efficiency and minimum heat generation.
CABINET DESIGN
The closed-cabinet design is low profile, flat fronted with curved sides. Carrying handles on the sides make for easy handling. The back panel comprises two large aluminium heatsinks for the power amplifiers with a central plate carrying the controls and connectors. Ventilation slots for the amplifiers and power supplies run across the top of the cabinet at the rear.
The sides and top of the cabinet are formed from painted Hornflex™, an MDF-based material. This innovative material makes possible the curved surfaces of the 328A that greatly reduce internal standing wave patterns, and hence practically eliminate colouration.
Four adhesive-backed rubber feet are supplied for positioning on the base of the unit as required.
