THX ARENDAL, Handbook

Page: 22 / 48

The heart of all Arendal speakers, our Tweeter utilizes
a 28mm synthetic soft dome with custom designed,
matching waveguide. The soft dome itself is sourced from
the high end stable of Dr. Kurt Mueller. It is very light
weight, totally pistonic to ultra high frequencies, optimally
damped, produced to exceedingly tight tolerances and
specifi cally chosen for its sweet sound character and
consistent frequency response.
The role of the waveguide is to take an already excellent
tweeter and provide refi nements to the tweeter’s
performance. The size and shape, although appearing
rather simple is in fact the result of painstaking modeling,
testing and refi nement. In precisely controlling directivity
across the tweeter’s frequency range, we are able to
broaden top end dispersion, which the tweeter naturally
wants to beam straight ahead and focus frequencies at
the bottom end of the tweeters range, which naturally
want to spread out in all directions. This provides a more
consistent polar response across the tweeters entire range
and provided a close match to the dispersion pattern of
the mid-bass driver it works with, simplifying crossover
design.
High effi ciency, high power motor
The motor of this tweeter is a Tour de Force. All components
are bespoke designs for Arendal Sound, extensively FEA
optimized. The result is a very wide bandwidth, high
effi ciency, low distortion tweeter capable of being crossed
over at very low 1500Hz, even at very high powers. This is
truly a rare combination of such low crossover point, high
output capability and clean sound.
• Large, high grade neodymium ring magnet.
• High temp polyimide CCAW wire.
• Underhung voice coil design.
• Copper and aluminum shorting rings.
• Ultra low viscosity Ferrofl uid contributes to voice
coil cooling and ensures the best possible transient
response.
• Large aluminum heatsink/shorting ring lowers
distortion and prevents thermal compression.
Hybrid aluminum & hdf waveguide
assembly
The fi nal piece to Arendal’s tweeter performance is
mating the dome with the custom matched, proprietary
waveguide, entirely optimised in-house. The waveguide
serves several purposes, augmenting tweeter performance
to a level that no fl at baffl e mounted single dome solution
could reproduce:
• Increased effi ciency by controlling lower frequency
dispersion - Typically a 6dB gain.
• Very low distortion due to increase in bottom end
effi ciency.
• Precise Polar Response control (sometime referred to
as directivity response control).
• Low crossover frequency (approx. 1 octave lower than
without the waveguide).
• Excellent directivity transition from mid/woofer to
tweeter.
WAVEGUIDE TWEETER