JBL HLA 4895, Руководство пользователя

Страница: 20 / 56

18
Amplifier rack panels
A labeled panel on the back of each amplifier rack fitted with individual female XLR connectors for
each channel will put them in plain view for system technicians, and saves wear to the amplifiers’ connectors.
Along with individual connections, multi-cable disconnects in parallel can be used to distribute signals in
portable systems to make setup quick and infallible. By placing all signals onto pre-assigned channels of a multi-
core snake dedicated for sending signals to the amps, correct hookup is rapid and certain. Dedicated send snakes
with 10 or 20 channels are common, with extra lines in the send snake often used for fill-in zones of speaker
coverage, intercom and talk-back functions.
Socapex fly-mult cables
Rather than run several individual 8-conductor cables to a speaker array up in the air, another
common cabling design is to run several circuits by using a 18-conductor cable with a Socapex-type connector
such as is used widely in theatrical tour lighting. One Socapex cable can carry power for four 4897 subs and a
second Socapex cable can carry power for two sets of four 4895 three-way speakers. At the back of the speaker
array an adapter changes the standard Socapex multi-connection back into several Neutrik connectors to
distribute power to the speakers: One Socapex-to-Speakon adapter fanning out to four 4897 subwoofer
connections, while a second Socapex-to-Speakon adapter fans out to two 4895 speaker connections, for two
groups of four 4895 speakers.
At the amplifier racks, panels with the two different kinds of Socapex assignments are connected to the
outputs of their respective amplifiers. Several companies in Europe have agreed on a circuit assignment design
for accomplishing this in order to promote inter-vendor compatibility. Note the “Low” circuit doubles up
conductors in the Socapex to allow for the higher current in that band of output. (There are other methods of
organizing the Socapex circuits for this application.)
EML European Socapex pin-out standard:
Socapex Pin (2) 4895 speakers - NL-8 pin (4) 4897 subs - NL-8 pin
1 1 Low 1
1
2
1
Sub 1
1
1
1
1 2 Low 1
`
2
`
Sub 1
1
2
1
1 3 Low 1
1
2
1
Sub 1
`
1
`
1 4 Low 1
`
2
`
Sub 1
`
2
`
1 5 Mid 1
1
3
1
Sub 2
1
1
1
1 6 Mid 1
`
3
`
Sub 2
1
2
1
1 7 High 1
1
4
1
Sub 2
`
1
`
1 8 High 1
`
4
`
Sub 2
`
2
`
1 9 Low 2
1
2
1
Sub 3
1
1
1
10 Low 2
`
2
`
Sub 3
1
2
1
11 Low 2
1
2
1
Sub 3
`
1
`
12 Low 2
`
2
`
Sub 3
`
2
`
13 Mid 2
1
3
1
Sub 4
1
1
1
14 Mid 2
`
3
`
Sub 4
1
2
1
15 High 2
1
4
1
Sub 4
`
1
`
16 High 2
`
4
`
Sub 4
`
2
`
17 n. c. n. c.
18 n. c. n. c.