541345

Allen-Heath GL2800 Manual

32
Zoom out
Zoom in
Previous page
1/42
Next page
32 GL2800 User Guide
Mix and Aux-Fed Subs Driving the PA system sub bass
speakers with their own mix has two main advantages. First, the mix
is much cleaner because only sources that generate the low
frequencies, for example kick drum, bass guitar, keyboards and
sound effects are sent to the subs. Low frequency bleed from these
sources into open microphones such as vocals and snare is
eliminated from the PA much more effectively than using just the
channel filters. Second, the sub bass amplifier is only working with
the sources needed. It is not wasting power reproducing unnecessary
pickup.
The subs can be separately driven in several ways. A common
method is to use the independent M mix. Route all sources to L-R.
Route the sources you want in the subs to both L-R and M. Feed the
LR to a stereo crossover to drive the top speakers, and M to a mono
crossover to drive the sub speakers. Refer to the speaker
manufacturer for recommended crossover frequency, usually within
the range 80Hz to 120Hz. The PA overall level is adjusted by moving
the L, R and M (sub) master faders together.
Another method that has become popular is to use an Aux mix to
drive the subs. This is referred to as ‘aux-fed subs’. Align the system
so that the normal unity gain position of the channel fader and aux
send result in the correct speaker balance. For sources you wish to
send to the sub, turn up the channel aux send to its unity 3 o’clock
position. Avoid the temptation to ride the aux send to create more or
less sub as this may upset the natural speaker balance or cause
problems for listeners in different parts of the room.
One problem with using the aux in this way is that it becomes difficult
to balance the top and sub speakers if you need to adjust the overall
volume of the PA. Typically the LR (tops) use fader masters, and the
aux is on a rotary master. The GL2800 overcomes this with the
monitor mode ‘REV’ switch that swaps the rotary aux master with the
related fader group master. This switch is recessed for protection
against accidental operation. This puts the aux (sub) master on to a
fader next to the PA tops master faders. The result is you get all
master faders aligned for simultaneous control, individual mutes and
meters, and three properly balanced XLR outputs. We recommend
that you use Aux 8 for the sub feed. This gives you 4 master faders
next to each other, for example, Subs, L, R and C.
Other M Output Applications Apart from the main PA C mix
or sub-bass speaker mix, other examples include L+R sum mono fill,
additional mono zone feed, mono recording, mono PA with LR
providing two more subgroups to M, engineers PAFL wedge feed…
and more.
Using the channel Direct Outputs
Recording - Default factory setting is pre-fade so that your live fader
mixing does not affect the recording. Use the channel recessed PRE-
EQ switches to select either post-EQ or pre-insert, pre-EQ for your
recording. Post-EQ lets you use the EQ for source correction affecting
the recording too. Select pre-EQ if you do not want your compressor
and EQ to affect the recording.
Monitor mixing - You could also patch DIR OUT into a matrix EXT IN
to add a ‘more me’ channel into a monitor send created from the
groups and LR. If preferred you can reconfigure the direct outputs to
post-fade by setting internal jumpers.
Single effects - Use post for feeding an effects processor with one
source only, for example a dedicated reverb on lead vocals or snare.
GRP8
AUX8
AFL
00
0
5
5
30
20
10
10
M
LISTEN
R
L
AUX9-10
10
10
20
30
5
5
0
00
10
10
20
30
5
5
0
00
10
10
20
30
5
5
0
00
MRL8
MUTE MUTE
SIG
0
+6
PK!
SIG
0
+6
PK!
SIG
0
+6
PK!
SIG
0
+6
PK!
0dBOO
L-R TO M
GRP8
TO LR
GRP8
TO M
MUTE
STEREO
+10OO
9-10
AUX
+10OO
8
AUX
AFL
REV REV
L
PAN
R
=
LRCAUX8
TOPSSUBS
GRP8
00
30
20
10
10
20
30
00
10
20
30
00
10
20
30
00
MRL8
LRSUBS
TOPS
(WEDGE)MOUT
OUT
DIRECT
… 32 …


Need help? Post your question in this forum.

Forumrules


Report abuse

Libble takes abuse of its services very seriously. We're committed to dealing with such abuse according to the laws in your country of residence. When you submit a report, we'll investigate it and take the appropriate action. We'll get back to you only if we require additional details or have more information to share.

Product:

For example, Anti-Semitic content, racist content, or material that could result in a violent physical act.

For example, a credit card number, a personal identification number, or an unlisted home address. Note that email addresses and full names are not considered private information.

Forumrules

To achieve meaningful questions, we apply the following rules:

Register

Register getting emails for Allen-Heath GL2800 at:


You will receive an email to register for one or both of the options.


Get your user manual by e-mail

Enter your email address to receive the manual of Allen-Heath GL2800 in the language / languages: English as an attachment in your email.

The manual is 7,65 mb in size.

 

You will receive the manual in your email within minutes. If you have not received an email, then probably have entered the wrong email address or your mailbox is too full. In addition, it may be that your ISP may have a maximum size for emails to receive.

The manual is sent by email. Check your email

If you have not received an email with the manual within fifteen minutes, it may be that you have a entered a wrong email address or that your ISP has set a maximum size to receive email that is smaller than the size of the manual.

The email address you have provided is not correct.

Please check the email address and correct it.

Your question is posted on this page

Would you like to receive an email when new answers and questions are posted? Please enter your email address.



Info