Meyer Sound M'elodie Operating Instructions Manual Download

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CHAPTER 3

NOTE:

For details on the M’elodie loud-

speaker’s audio input characteristics and

ampliﬁcation, see Appendix C.

AMPLIFICATION AND PROTECTION CIRCUITRY

M’elodie is powered by Meyer Sound MP-1/M’elodie ampli-
ﬁer modules in a three-channel ampliﬁer conﬁguration with
a total power of 1275 watts (2550 watts peak). The MP-1/
M’elodie ampliﬁer utilizes complementary-power MOSFET
output stages (class AB/H). All the speciﬁc functions for the
M’elodie loudspeaker such as crossover points, frequency
and phase response, and driver protection are determined
by the control card installed in one of the MP-1/M’elodie
ampliﬁer modules.

CAUTION:

Please note that M’elodie and

other Meyer Sound loudspeaker ampliﬁers

are different. Speciﬁc functions for each model,
such as crossover points, frequency and phase
correction and driver protection are determined by
the control cards installed inside the ampliﬁer. Do
not exchange ampliﬁers between M’elodie and other
Meyer Sound loudspeakers.

M’ELODIE INTERCONNECTIONS

The two 4-ohm, 8-inch, low-frequency cone drivers are
each powered with 500 watts from two MP-1 channels of
the three-channel M’elodie ampliﬁer. The 3-inch diaphragm,
8-ohm, high-frequency compression driver is powered with
275 watts from the third MP-1 channel.

All Meyer Sound loudspeakers are tested and shipped
with the drivers in correct alignment. If a driver needs to be
replaced, make sure the replacement is reinstalled with the
correct polarity.

CAUTION:

Failure to connect a replacement

driver using the proper polarity will result

in severe degradation in frequency and phase
response and can harm the drivers and ampliﬁer.

CABLING

The M’elodie system uses three separate cables and con-
nectors per cabinet for the AC line current, signal, and RMS
data. However, the three can be consolidated to create a
“multi-cable” by looming them together for quick connec-
tion to each cabinet.

THE LIMITING SYSTEM

Low- and Mid-Frequency Limiters

The M’elodie loudspeaker’s left and right 8-inch cone driv-
ers are powered by separate ampliﬁer channels, each with
a detector but routed to one limiter; the limiter tracks both
channels and uses the higher of the two values to engage.
By limiting both ampliﬁer channels equally, any anomalies
in the frequency range shared by the drivers are elimi-
nated during limiting. The lower limit LED on the user panel
indicates limiting activity for these two drivers. When the
level for both low channels returns to normal — below the
limiter’s threshold — the limiter will cease operation.

Network

tiv

ity

R e m o t e M o n i t o r S y s t e m

RMS3

Firmware

Looping Audio Input
10k

Ω

Balanced

Input

Loop

AC LOOP OUTPUT

115/230V

50-60 Hz

10A RMS @115V

12.5A RMS @230V

Class 1 Wiring

AC INPUT RATING

115/230V

50-60 Hz

5A RMS @115V

2.5A RMS @230V

1500W BURST MAX

Figure 3.4: The limit LEDs on the user panel indicate high-frequency and
low-frequency limiter activity

High-Frequency Limiter

The 3-inch diaphragm, high-frequency compression driver
is powered by a single channel with its own detector. The
upper Limit LED is used to indicate any limiting activity for
the high-frequency driver. When engaged, the limiter not
only protects the driver, but also prevents signal peaks
from causing excessive distortion in the ampliﬁer channel,
preserving headroom and maintaining smooth frequency
response at high levels. When the level returns to normal
— below the limiter’s threshold — the limiter will cease
operation.

CAUTION:

The limit LEDs indicate when the

safe power level is exceeded. If any channel

on a system of M’elodie loudspeakers begins to limit
before reaching the required sound pressure level
(SPL), consider adding more loudspeakers to satisfy
the SPL requirements. This will avoid exposing the
drivers on that channel to excessive heat and/or
excursion, reducing the life-span of the drivers.

high-frequency LED (yellow)

low-frequency LED (yellow)