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HA1500 HD-A
®
Balanced Woofer
The Whise 1500 HD-A
®
subwoofer recreates bass with incredibly low levels of
distortion, and amazing power efficiency. Using PAM™, VR/UR™ and NTM
®
digital crossovers enables precise control of frequency signals giving the Whise
1500 HD-A
®
balanced subwoofer a proprietary advantage over competitors with
use conventional alternatives.
NTM
®
(Neville Thiele Method) Crossover
This crossover design was developed by the legendary Neville Thiele, who
helped formulate the Thiele/Small equations upon which all modern loudspeaker
design is based. It is used to handle the critical crossover region of this hybrid
speaker to give incredibly tight frequency control and a seamless transition
between the woofer and the electrostatic array.
NTM
®
crossovers are exact summing, steep roll off crossovers. As the name
suggests, they were invented by Neville Thiele and are protected by patents
owned by Immersion Technologies International plc.
They have the rare advantage of providing a steep roll off with low group delay
as well as a behaved phase response.
•
NTM
®
crossovers eliminate the breadth of interference region between
bands to the extent that interference becomes negligible.
•
NTM
®
crossovers have significantly reduced group delay variation
compared to conventional crossovers of equivalent steepness.
•
In analogue implementations, NTM
®
crossovers have substantially lower
component counts than conventional systems of equivalent steepness.
This is because low order NTM
®
crossovers give steep roll offs, whereas
with conventional systems a high order crossover is required to get a
steep roll off.
PAM™ (Parametric Acoustic Modeling)
PAM™ is a computer aided modelling technique for loudspeakers. It is an
advance on all pre-existing loudspeaker simulation applications in that it
represents waveguides as distributed parameters. Superficially this may seem a
trivial advance, but it enables the simulation of impedance discontinuities to
behave correctly and thus has enormous significance for all forms of
waveguides. In particular it enables waveguides to be structured with custom
profiles for particular applications and it provides the designer with significant
flexibility to tailor the response of a loudspeaker in a predictable way.