Line Arrays; Installation; Installation Of A Single System; Combination Of Several L-Ray/1000 Units - IMG STAGELINE L-RAY/1000 Mode D'emploi

3.1 Line arrays

Single speakers act similar to point sound
sources when dispersing the sound. Their sound
radiation is spherical and the sound pressure
level is reduced by 6 dB when doubling the dis-
tance to the sound source. For PA application of
larger venues, this means that the volume at the
stage must already have a very high level so that
there will still be sufficient sound at a distance.
If an infinite number of speakers is used
which are arranged one above the other and if
their distance between each other is relatively
small regarding the wavelength of the frequen-
cies to be radiated (coherent coupling), these
speakers act together like a line sound source.
The sound radiation of a line source is cylindrical
and the sound pressure level is only reduced by
3 dB when dou bling the distance to the sound
source. This effect is used for a line array
speaker system.
As of course only a finite number of speak-
ers can be used, the sound radiation only acts in
a certain PA range similar to a line source. The
more speak ers are combined, the more powerful
is the effect. The advantage of such a speaker
system is a larger range compared to standard
systems, i. e. less power is required and the vol-
ume at the stage can be lower, which will also
protect the hearing of the audience close to the
stage. In addition, disturbing interference will be
prevented by the close vertical speaker arrange-
ment. This occurs when several speaker sys-
tems are grouped horizontally (clus tered) which
is common and leads to phase extinction and
uneven sound dispersion in the PA range.
As the splay angle between the single ele-
ments of a line array can be adjusted individu-
ally, all speakers can be arranged in a curving
way so that an even sound field for the respec-
tive auditorium is reached.

4 Installation

WARNING Installations which are not made
in an expert way are a potential
danger, especially if systems are
flown above persons. Therefore,
the installation must only be made
by expert personnel familiar with
the valid standards and safety reg-
ulations.
The installation, especially the stability of the
mounting connections, must be checked
accordingly at regular intervals.

4.1 Installation of a single system

4.1.1 Mounting (fig. 2)
1) For flying (suspending, fig. 3) the system,
tightly screw the four ring bolts (13) in the
threads on the upper side of the flight frame
(14). Safely suspend the flight frame from all
four ring bolts.
The system can also be ground-stacked
( fig. 4): Instead of the ring bolts, tightly
screw the rubber feet to the frame and place
the frame on a safe ground. The indications
of direction "above" and "below" used in the
following descriptions refer to the suspended
mounting and have to be replaced accord-
ingly for ground stacking.
2) Place the vertical mounting rails at the edges
of the bass speaker unit (15) onto the four
connecting plates that stick out from the flight
frame (14) and tighten them with four ball lock
bolts.
Press the pin to unlock the bolt, put the
bolt through the drill holes up to the stop and
then release the pin. Always check the con-
nection and make sure that the bolt cannot be
removed without unlocking.
3) Use two ball lock bolts (16) to connect the
front side of the first of the four mid-high
range speaker units (17) to the bass speaker
unit.
4) As shown in fig. 2, connect the rear side of the
upper mid-high range speaker to the mount-
ing profile (18) on the bass speaker unit by
means of a hexagon socket screw, two ball
lock bolts and the connecting plate (19).
5) Connect the other mid-high range speakers
at the front side with each other, using two
ball lock bolts for each connection.
6) Connect the mid-high range speaker units
with each other at the rear side. A curved
form of the speaker system may be useful to
achieve an even sound distribution. For this
purpose, the angles between the mid-high
range speaker units can be adjusted individ-
ually:
As shown in the lower detailed view of fig. 2,
attach the connecting plate (20) to the lower
mid-high range speaker, using a hexagon
socket screw. Attach the connecting plate to
the upper mid-high range unit, using a ball
lock bolt; select the appropriate drill holes to
set the desired angle between the two mid-
high range speakers.
4.1.2 Connection
1) As a signal source, connect an audio unit with
line output (e. g. mixer, preamplifier, etc.) to
the XLR jack LINE INPUT (12). The XLR
jacks are balanced, but they may be con-
nected in an un balanced way via correspon-
ding adapters.
2) The input signal for routing is available at the
output LINE OUTPUT (11). Here, further ampli-
fier systems for additional PA applications may
be connected (compare chapter 4.2.2).
3) Connect the jack IN on the rear side of the
first mid-high range speaker unit to one of the
jacks MID / HIGH OUTPUT (4) of the bass
speaker unit.
Connect the plugs to the corresponding
jacks and turn them clockwise until they lock.
To remove the plug, pull back the safety latch
on the plug and turn the plug counter-clock-
wise.
4) Connect the jack OUT on the rear side of the
first mid-high range speaker unit to the jack
IN of the next mid-high range speaker unit.
Connect the second mid-high range speaker
unit to the third and the third to the fourth in
the same way.
5) If desired, connect a data line from a PC, de -
pending on the kind of the interface used, to
the jack USB (7), RS-232 (8), or RS-485
INPUT (5). The RS-485 input signal is avail-
able at the jack RS-485 OUTPUT (6) for rout-
ing it to another system (compare chapter 6).
6) Insert the blue Powercon plug of the mains
cable supplied into the Powercon jack (3) and
then turn it clockwise until it locks. (To dis-
connect the cable from the unit, pull back the
safety latch on the plug, turn the plug
counter-clockwise and remove the plug from
the jack.) Then connect the mains plug of the
cable to a mains socket (230 V/ 50 Hz).
Important: Never connect or disconnect a
Powercon plug while voltage is applied.
Always make the Powercon connection
before making the mains connection. When
disconnecting, always disconnect the mains
connection before disconnecting the Power-
con connection.
Make sure that the current circuit to which the
unit is connected is protected by a fuse with
the appropriate current rating.
4.2 Combination of several
L-RAY/ 1000 units
For PA applications of larger areas, several
L-RAY/ 1000 units may be combined. Up to four
systems may be mounted with each other
( fig. 6).
4.2.1 Mounting (figs. 5 and 6)
1) For flying (suspending) the system, tightly
screw in the four ring bolts (13) in the threads
on the upper side of the flight frame (14).
Safely suspend the flight frame from all four
ring bolts.
The system can also be ground-stacked
( fig. 4): Instead of the ring bolts, tightly
screw the rubber feet to the frame and place
the frame on a safe ground. The indications
of direction "above" and "below" used in the
fol lowing descriptions refer to the suspended
mounting and have to be exchanged accord-
ingly for ground stacking.
2) Place the vertical mounting rails at the edges
of the first bass speaker unit (15) onto the
four connecting plates that stick out of the
flight frame (14) and tighten them with four
ball lock bolts.
Press the pin to unlock the bolt, put the
bolt through the drill holes up to the stop and
then release the pin. Always check the con-
nection and make sure that the bolt cannot be
removed without unlocking.
Remove the mounting profile (18) on the
lower side of the bass speaker unit by releas-
ing the screws.
3) Connect the bass speaker unit of the second
system to the first bass speaker system,
using four ball lock bolts. To add further sys-
tems, remove the mounting profile from this
bass speaker unit as well and mount the next
bass speaker units to this bass speaker unit
in the same way.
4) Use two ball lock bolts (16) to connect the
front side of the first mid-high range speaker
unit to the lowest bass speaker unit.
5) As shown in fig. 2, connect the rear side of the
upper mid-high range speaker to the mount-
ing profile (18) on the bass speaker unit by
means of a hexagon socket screw, two ball
lock bolts and the connecting plate (19).
6) Connect the other mid-high range speakers
at the front side with each other, using two
ball lock bolts for each connection.
7) Connect the mid-high range speaker units
with each other at the rear side. A curved
form of the speaker system may be useful to
achieve an even sound distribution. For this
purpose, the angles between the mid-high
range speaker units can be adjusted individ-
ually:
As shown in the lower detailed view of fig. 2,
attach the connecting plate (20) to the lower
mid-high range speaker, using a hexagon
screw socket. Attach the connecting plate to
the upper mid-high range unit, using a ball
lock bolt; select the appropriate drill holes to
set the desired angle between the two mid-
high range speakers.
11