MARENIUS ELEKTRONIKUTVECKLING AB |
www.marenius.se
|
www.marenius.com
|
www.audiodesign.pro
4/4/2014 MM-4240 User Manual v.2.00
18
10.4. Limiters
Each channel has a high quality ultralow THD opto-limiter. The limiter is assigned to the
channel fader and can be enabled in the menu. Since the limiter only addresses the channel
fader a pre-
gain clip won’t be limited. The limiter parameters are listed in the table below.
Limiter parameters
Attack time
2mS
Release time
200mS
THD limiting (1kHz sine)
0.3%
Limiter threshold
+8dBu
10.4.1. Taking maximum advantage of the limiters
The limiters are only assigned to the channel faders and hence only active if the signal after the
pre-gain is clipped. Clipping at the pre-gain stage will not be handled.
To maximize the limiters potential the follow steps shall be carried out:
1. Turn up the pre-
gain until it is clipping at a “normal” input level
2. Turn down the pre-gain 12-24dB (2-4 steps)
3. Turn up the channel fader to max.
10.5. Master fader
The master fader allows the user to fade in and fade out the mix.
The master fader has a digital gain stage allowing the mix to be gained up +6dB.
The fader can also be used as volume control when playing tracks from the SD card, this
feature can be enabled in the menu. The scale of the master fader is absolute and the same
scale is used when enabled in playback mode.
10.6. Panning
The panning knob is the outer knob of the lower concentric potentiometer. The MM-4240 uses a
straight -6dB panning stage, this means that when the panning potentiometer is straight up,
50% of the input signal is sent to the left channel and 50% of the input signal is sent to the right
channel.
10.7. Mixing
The mixing stage of the MM-4240 is a classic summing mixer. Since all input signals are added
together the mix may be clipped. The user must be aware of the fact that two identical input
signals summed together will result in a 6dB higher output signal. If the mix is clipped this is
shown as a “CLP” symbol next to the R and/or L meter in the display.
10.8. Test tone
The 1 kHz test tone can be enabled with the test tone switch on the front panel. The test tone
level is set to -18dBFS and will appear on all analog output busses. The test tone will also
appear on the digital outpu
ts if the digital multiplexer is set to “MST”. The test tone level follows
the menu configured nominal level of the output, for example if the nominal level is set to +4dBu
the test tone output signal will be -14dBu.
