Acoustic Design; Low Frequency - Martin Audio MLA User Manual

MLA System
USER GUIDE
the fore and index fingers pulling the pin whilst your thumb depresses the central button, a very quick and easy operation. When
using the pins to link cabinets, the central button must again be depressed so the pin can be pushed into position. It is important
to check that the central button does not remain depressed once you have put it in place as this would indicate that the pin has
not been pushed all the way into position and the ball bearings at the end of the pin have not been able to pop out and lock the
pin in place. If the pin is not locked the array is unsafe. The pin MUST be repositioned until it is securely locked in place.

Acoustic Design

The MLA Compact acoustic design took the MLA cabinet as a starting point and scaled the design down to fit the smaller
enclosure. Many of the key attributes in the MLA have been repeated including the all horn loaded design and Hybrid® low
frequency section. This approach – something of a Martin Audio trademark – allows maximum efficiency from the system, the
output from the Compact is astonishing for such a small box. MLA Compact deliberately avoids the use of coaxial, co-entrant or
cross-firing midrange/HF driver arrangements which introduce acoustic discontinuities that affect the on and off-axis frequency
response of both mid and HF sections. The MLA Compact's mid and HF horns are completely separate – a key factor in its ability
to produce consistent horizontal constant directivity coverage. This gives startlingly consistent frequency response when
listening off-axis and "walking the field".
The cabinet has a wider dispersion than MLA as befitting its intended market and covers 100⁰ horizontal and 10⁰ vertical. Note
that as the vertical coverage is significantly greater than the MLA the MLA Compact system does not require a dedicated down-
fill enclosure.

Low Frequency

MLA Compact's LF section utilises 2 × 10"(250mm)/2.5"(63mm) voice coil, neodymium drive units in a unique Hybrid®
configuration. Each driver is slot-loaded into a truncated horn with a low flare rate, to give a high sensitivity of 103dB @ 1m/2.83V
— whilst the rear of the driver is reflex loaded to extend the LF output. MLA Compact's Hybrid LF arrangement provides the best
of both worlds — raising the acoustic efficiency and packing a punch that direct radiators cannot compete with, as well as
maintaining the LF extension.
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