THX ARENDAL, Handbook

Page: 36 / 48

Enclosure tuning
The Monitor, Center and Tower enclosures offer the
alternative of being used in a vented alignment. By
removing the foam plugs inside the ports, low frequency
-3dB point can be extended and given different bass
characteristics. Damping and therefore impulse response
are slightly less optimal than the sealed alignment, but
the extended response delivers more bass output down to
the ports tuning frequency.
Larger rooms and/or speaker positions further from room
boundaries, may value this extra natural output as they
will be less supported than in a smaller room.
Tower
The Tower has the added fl exibility of plugging different
combinations of the 3 ports. With all three 3 ports open
maximum bass output is guaranteed, but with a higher
roll-off point. With two 2 ports open, the -3dB point is
lowered and the response curve starts to shelve down
from roughly where the sealed alignment would, but at a
lower rate of roll-off. With one port open, the -3dB point is
lower still, but with an increased rate of roll off. All ports
plugged brings the Tower back to a fully sealed alignment.
The Tower therefore delivers a choice of multiple roll-off,
output and damping ‘tunes’ that will suit a wide variety of
tastes, room acoustics and speaker placement.
Please Note: With only a single port open, higher listening
levels could generate some port noise (sometimes called
‘port chuff’) from the extremely high velocities of the air
HOW TO CONNECT
within the port. It is therefore not recommended for high
SPL listening, but may perform quite well at moderate
levels.
Monitor & Center
In the case of the Monitor and Center, we recommend
only fully sealed, or fully ported operation, in line with
the recommendations above with respect to room type
and positioning. Although remarkably bass profi cient, it
is envisaged that the Monitor and Center will typically be
supported by a subwoofer for maximum bass extension
and will therefore always perform at its optimum when
run sealed in this situation.
Connectivity
All Arendal Sound 1723 Speakers offer the possibility of
Bi-amp & Bi-wire, as well as normal single wire operation.
In all cases the tweeter (High) crossover is electrically
separated from the mid/bass (Low) crossover, by removing
the external jumper plates that come fi tted between the
top and bottom pairs of speaker input terminals. If using
separate amplifi ers to power the high & low speaker
inputs, care should taken to ensure the power amplifi ers
are gain matched, to prevent an imbalance in the output
of the drivers.
NEVER connect across the high pair of terminals, or the
low pair of terminals using the jumper plates or other
cable, while the amplifi er is connected. This will result in
permanent damage to your amplifi er. Always shut down
the amplifi er when connecting the speakers.