Meyer Sound M'elodie, Operating Instructions Manual

21

CHAPTER 5

Using Meyer Sound Processors to Drive and 

Optimize the Array

The Galileo 616 loudspeaker management system and the 
LD-3 compensating line driver are specifically designed to 
allow you to follow these optimization strategies: 

■ 

The array can be divided in zones.

■ 

The atmospheric correction capabilities of these 
processors compensates for the air absorption of the 
air at high frequencies. Each section allows different 
correction settings according to the distance of each 
section’s intended coverage.

■ 

The processors effectively manage low-frequency build-
up in the array and correct all zones of the array with 
the same correction at low frequencies.

In addition to their unique atmospheric correction for 
high frequencies and their low-frequency compensation 
capabilities, these Meyer Sound processors feature:

■ 

Low-pass and high-pass filters with minimal phase shift 
that can effectively integrate subwoofers with M’elodie 
arrays.

■ 

Robust output line drivers that easily drive Meyer Sound 
self-powered systems over long cable runs.

Figure 5.4. 

The LD-3 air attenuation compensating line driver

NOTE:

The MILO or M1D setting in the  

LD-3’s Array Correction section can be used 

effectively with M’elodie, adjusting the Array Size for 
the equivalent length of the array. For example, the 
length of 6 M’elodies is approximately equivalent 
to 8 M1Ds or 4 MILOs. The size relationship is not 
exact, so you may need to adjust the Array Size 
number up or down for the best result. 

The Galileo loudspeaker management system is a 
hardware/software system providing all of the facilities 
required to drive and align sound reinforcement systems, 
and offering fixed low latency across each output. The 
Galileo 616 is a 2U, 6-input/16-output fully digital matrix 
processor. Compass software provides comprehensive 
control of the Galileo 616 via a graphical user interface (GUI) 
running on a remote computer, or controlled directly from 
the processor front panel.

Designed as the perfect complement to Meyer Sound’s  
self-powered loudspeakers and interfacing directly with the 
SIM 3 audio analyzer, the Galileo system includes digital 
delay lines as well as digital implementations of popular 
features developed over years by Meyer Sound for its 
acclaimed analog processors, including air absorption 
compensation filters, array correction, and equalization  
from the CP-10 and VX-1.

Figure 5.5. 

Galileo 616 Loudspeaker Management System

For more information on Galileo and its Compass control 
software, please visit www.meyersound.com.

Using Digital Signal Processors

Full-range signals may be applied to Meyer Sound’s self-
powered loudspeakers because they have built-in active 
crossover circuits; external crossovers and digital signal 
processors (DSP) are optional and should be used very 
carefully due to phase shifts that can cause cancellations.

If DSP is used, all zones in a M’elodie array as well 
as the subwoofers should be fed from the same DSP 
in order to keep their delay time the same. Otherwise 
you may experience phase shift differences among the 
M’elodie loudspeakers in the array and between M’elodie 
loudspeakers and the subwoofers. In addition, you should 
verify the delay time between channels: Some DSPs may 
develop channel-to-channel variations in delay when the 
DSP is near maximum throughput, which becomes more 
likely as the number of filters the DSP is using increases.

In no case should a filter higher than 2nd order be used to 
optimize the interaction between the M’elodie array and 
the subwoofers. The additional phase shift introduced 
deteriorates the impulse response and higher roll-off does 
not improve crossover interaction.

TIP:

Some filters on the Galileo and  

LD-3 are parabolic filters with minimal 

phase shift, designed specifically to optimize the 
interaction between M’elodie and subwoofers; most 
commercially available DSP devices have no presets 
to emulate these minimum-phase parabolic filters.

In addition, if the loudspeakers are going to be driven 
directly from the DSP, verify that the outputs of the 
processor have the driving capabilities to drive the total 
load presented by the loudspeakers connected to it. Please 
refer to the Audio Input section on page 11 of this manual.