MUSICSON DP SYSTEMS User manual

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DP SYSTEMS USER MANUAL
1.- INTRODUCTION ...................................... Page 2-10
1.1.- DP-3 SYSTEM ............................... Page 3-7
1.1.1.- DP-H ENCLOSURE ................... Page 4,5
1.1.2.- DP-SB ENCLOSURE................... Page 6,7
1.2.- DP-4 SYSTEM .............................. Page 8-10
1.2.1.- DP-G ENCLOSURE.................... Page 8,9
1.2.2. - SUB218BS ENCLOSURE............... Page 10
2. - ELECTRONICS AND AMPLIFICATION..................... Page 11-13
2.1. - DP-3 SYSTEM............................... Page 11,12
2.2. - DP-4 SYSTEM............................... Page 12,13
3. - SYSTEM WIRING SCHEMATICS.... ..................... Page 14,15
4. - DP-SYSTEM SPARE PARTS ............................ Page 16,17
5. - SYSTEM SETUP...................................... Page 17-20
5.1. - DP-3 SYSTEM............................... Page 17-19
5.2. - DP-4 SYSTEM............................... Page 19,20
6. - CONTROL ELECTRONICS............................... Page 21-27
6.1. - ISP-2022 ................................. Page 21-24
6.2. - ISP-1014 ................................. Page 24-27
7. - CURVES ......................................... Page 28-31
7.1. - RESPONSE CURVES .......................... Page 28,29
7.2. - POLAR GRAPHICS ......................... Page 29-31
8. - SETUP RECOMMENDATIONS. ELEVATIONS SYSTEMS ........ page 32-37
8.1. - DP-3 SYSTEM............................... page 32,33
8.2. - DP-4 SYSTEM............................... Page 33-37
9. - USEFUL SETUPS WITH THE DP-4....................... Page 37-41
10. - WARRANTY EXTENSIÓN...............................-+ Page 42
WE, AT MUSICSON WANT TO THANK YOU FOR THE TRUST SHOWN TOWARDS OUR PRODUCTS.
PLEASE READ THIS MANUAL CAREFULLY BEFORE STARTING YOUR NEW DP-3 OR DP-4
SYSTEM, IN ORDER TO AVOID ANY KIND OF PROBLEM AND TO OBTAIN ITS HIGHEST
PERFORMANCE. REMEMBER THAT YOU HAVE JUST OBTAINED A HIGH-TECHNOLOGY PRODUCT.
IN ORDER TO CONTACT US FOR ANY REASON, PLEASE SEE OUR WEB SITE.
WEB: www.musicson.com
E-MAIL: [e-mail]

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1. - INTRODUCTION
The new DP product line, which has been developed and manufactured by
Musicson, conceals an important technological step forward in sound
reinforcement. Its applications range from live concerts to recorded music
in open spaces or closed rooms.
Musicson's engineers have used state-of-the-art last generation software
tools in order to simulate acoustic elements as well as to produce the
corresponding prototypes.
The different frequency ways that form the DP-series have been optimised,
even before producing the prototypes, through several simulation processes.
In order to develop the low- frequency units, a special care has been
taking, not only simulating the differences in frequency response and
performance, but also further factors have been taken care of for the first
time.
Maximum excursion of the mobile parts of the speakers have been optimised
by acting on the geometry of the enclosures, resonance frequency, length and
width of wave-guiding every elements that form, for example, a folded horn
unit.
On top of this, very concrete filters have been used within the ISP-1014 and
the ISP-2022 dynamics processors in order to achieve an optimal frequency
response and a minimum loudspeaker excursion, resulting in a reduced
mechanical fatigue of these elements.
On the other hand, equally important factors, such as the sound pressure
level, acoustic power, extreme current and voltage values at the speaker
poles, speed and acceleration of the electro acoustic elements and the air
moved within the enclosures and through the vents, etc.
The simulation software has also been used in order to optimise high and
mid- frequency band functioning, something almost unthinkable some years
ago. A linear frequency response, effective bandwidth, sound pressure and
also factors such as directivity, horizontal and vertical spread, possible
frequency overlapping produced through horns and phase plugs, depending on
the distance to the audience, are all factors that have received careful and
in-depth attention.
In an ongoing step, all this information has been checked and adjusted
with the first prototypes through different audio analysis software.
All this has resulted in the final development of the DP sound systems,
formed by four different enclosures and two signal processors, power
control, that are designed to perfectly fit together for an optimum
performance, frequency response and functional parameters.

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1.1. - DP-3 SYSTEM
The first system developed with these four enclosures is the DP-3.This is an
active three-way system, featuring three different enclosures: The DP-H for
the reproduction of high-mid frequencies and two equally shaped enclosures
to reproduce low and very-low frequencies: DP-SB1 and DP-SB2. This whole
system is controlled through the ISP-1014 processor.
1.1.1.-DP-H ENCLOSURE
The DP-H enclosure is an active-two-way acoustic system to reproduce
high-mid frequencies, conceived as al long-throw unit for great musical
indoor and outdoor events.
Both ways are built onto their own horn, optimised to completely control
their dispersion angles.
For the reproduction of the medium frequencies, a 12” speaker with a 3”
(77 mm) moving coil, mounted on an enhanced magnetic system, has been used
in order to increase performance without increasing harmonic distortion.
Also, the output surface has been reduced to 14 cm (5.5”) to increase its
efficiency. This has been achieved through the design of an innovative phase
plug, built with three concentric independent pieces. This allows us to have
a constant distance between the cone surface and the throat, eliminating
phase cancellations produced in other phase plug types such as ob’s or
bullets. The speaker also features cooling elements for the moving coil,
allowing higher power levels and, at the same time, and much lower power
compression through heat. The cone has received a special coating that
avoids deformation through higher-pressure levels, translated into lower
harmonic distortion at high power levels and protecting it against adverse
external agents such as humidity. Through all this an extremely flat
frequency response up to 1200 Hz is achieved (together with the use of the

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ISP-1014), offering, thus, a high level of clarity and intelligibility
within the vocal frequency range.
For the high and high-mid frequencies, we have used a 4” (100mm)
diaphragm, 2”-throat compression driver. This driver from ARP features very
special characteristics.
1.-An optimised magnetic structure has been used for maximum efficiency.
In order to achieve this, a Neodymium magnet has been used, offering:
a. - 20% more induction in the magnetic gap, increasing the energy
transferred to the coil and, thus, to the moving system. This means an
average performance increase of 2dB to the 2” driver, this being especially
significant for frequency higher than 100 Hz, where this increase reaches up
to 4dB. A linear response up to 20 kHz is achieved this way.
b. - A reduction in weight of 45% and 25% in the overall diameter.
2. - On the other hand, a titanium diaphragm with a special configuration
has been used in order to reduce harmonic distortion. The membrane is fixed
to a suspension made of a technical polymer. The use of this polymer has two
reasons: first, the self-resonance of this material is lower within the
audible frequency range, when used at high power levels, second, this
material is more resistant to deformation through diaphragm excursion. It
has been proven that titanium suspensions deteriorate the frequency response
and increase distortion levels after 3 to 5 years of use, within this size
of drivers. The mechanical resistance of these materials is much higher,
almost doubling their life cycle.
In order to optimise the frequency response, an exponential horn has been
used, allowing the system to perform without losses up to 19500 Hz.
This enclosure includes a rigging system to configure clusters, which
enhance the sound spread and throw. It includes also a front grille, covered
with a sturdy filtering technical foam to protect the speakers. (Only DP-4)

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TECHNICAL SPECIFICATION FOR MID FREQUENCIES
-SPL ( 1W/1m )............ 108.5 dB
-Max. SPL (Cont.)......... 133.5 dB (Calculated)
-Covering (dispersion).... 60 x 40º
-RMS Power................ 350 W
-Impedance................ 8 Ohm
-Frequency response....... 220-1200 Hz (con ISP-1014)
TECHNICAL SPECIFICATION FOR HIGH FREQUENCIES
-SPL ( 1W/1m )........... 112 dB
-Max. SPL (Continuo)..... 130.5 dB (Calculado)
-Covering (dispersion)... 40º x 20º (Hasta 10 KHz)
-RMS Power............... 150 W
-Impedance............... 8 Ohm
-Frequency response...... 1200-19500 Hz (con ISP-1014)
RESPONSE OF MID FREQUENCIES, HIGH FREQUENCIES
AND DP-H ENCLOSURE (WITH ISP-1014)

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1.1.2.- DP-SB ENCLOSURE
This enclosure is to be configured with the DP-H to form the DP-3 live sound
system.
For bass and sub bass frequency sound reinforcement, a folded horn enclosure
has been developed and optimised, in order to ensure high performance levels
with “kicking” basses and really deep sub basses.
Special care has been taken in the design and optimisation of the wave-
guiding parts of the enclosure, including throats, openings and lengths of
each one. The result is a best-possible response with a minimum speaker
excursion. This way a linear response and a bandwidth, reaching from 45 Hz
to 220 Hz, have been achieved, performing an SPL of 102 dB 1W/m.
To configure a DP-3 system, two units are needed, called DP_SB1 and DP-
SB2, which are equal and use a 700 W 18” speaker each. MUSICSON engineers
have also optimised this speaker, in order to improve their response within
this type of enclosure.
On one hand, a more powerful magnetic structure is used to improve the
speaker’s dynamics, enhancing the transient response. At the same time, a 4”
(100mm) moving coil, mounted on a Kapton® former, is used. The thermally
efficient copper is wound on both sides of the former, achieving higher heat
dissipation and structural stiffness. This allows the power application of
700W RMS (3000 W peak).
Also the height of the coil has been enlarged, in order to allow a greater
excursion. In order to improve the cooling of the coil, two cooling vents
are present, different from the conventional single cooling vent.
It includes also a front grille, covered with a sturdy filtering technical
foam to protect the speakers.

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TECHNICAL SPECIFICATIONS (EACH ENCLOSURE)
-SPL ( 1W/1m )............ 102.5 dB
-Max. SPL (Continuo)...... 131 dB (Calculated)
-RMS Power................ 750 W
-Impedance................ 8 Ohm
-Frequency response....... 45-220 Hz -3dB (with ISP-1014)
RESPONSE OF THE DP-SB ENCLOSURE (WITH ISP-1014)
1.2.-DP-4 SYSTEM
This next, more sophisticated sound system is configured through four
active ways. Therefore, the enclosure model DP-H is used for high-mid
frequencies, as described earlier. A second enclosure, the DP-G, is added to
reproduce bass frequencies and the SUB-218BS for the sub bass range,
including slight modifications to its predecessor to adapt it to the DP
series. The whole configuration is controlled through the ISP-2022 processor
for the SUB-218BS and through the newly developed ISP-1014 for the other
three frequency ways.
As the DP-H has already been described in the previous section, we will
now proceed with the details of the other components:

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1.2.1.-DP-G ENCLOSURE
The DP-G enclosure is conceived to reproduce the bass frequency range. It
will only be used with the 4-way active DP-4 configuration.
This enclosure is designed as a double sixth order band-pass system. This
configuration allows higher sound pressure levels within a narrower band
than other systems, such as reflex or hermetic systems. Through a correct
approximation, its two points of minimum excursion can be set within the
working range, thus reducing its overall mean excursion by 40% at the same
power level. This allows us to apply more power to the speakers and increase
the longevity of the mobile elements at the same time, keeping performance
and response at the original levels.
The DP-G uses two identical 500 W rms 15” loudspeakers, featuring a 4”
(100mm) coil, wound on a Kapton® former fixed onto a double spider and
mounted on a powerful magnetic system. All this results in a reproduction of
kicking basses.
This enclosure includes a rigging system to configure clusters, which
enhance the sound spread and throw. It includes also a front grille, covered
with a sturdy filtering technical foam to protect the speakers.

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TECHNICAL SPECIFICATIONS
-SPL ( 1W/1m )............ 105 dB
-Max. SPL (Cont.)......... 137 dB
-RMS Power................ 1000 W
-Impedance................ 4 Ohm
-Frequency response....... 65-220 Hz (con ISP-1014)
RESPONSE OF THE DP-G (WITH ISP-1014)
1.2.2.- SUB-218BS ENGLOSURE
This enclosure acts as a sub bass reinforcement system, used with the DP-
4 sound system. It is built as a reflex box, using two identical 18”
speakers. Its inside and the measures and shape of the vents have been

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carefully studied to optimise the functioning of the loudspeakers. Through
its new design, the frequency response has been enhanced and the excursion
of the mobile components has been minimised. Together with the ISP-2022, its
frequency response ranges from 28,5 Hz to 90 Hz (-3 dB), resulting in a very
deep and powerful sub bass response.
It includes also a front grille, adding stiffness to the system and it is
covered with sturdy, highly resistant filtering technical foam. It also
includes 100mm casters to ease handling.
TECHNICAL SPECIFICATIONS
-SPL ( 1W/1m )............ 102 dB
-Max. SPL (Cont.)......... 134 dB
-RMS Power................ 1200 W
-Impedance................ 4 Ohm
-Frequency response....... 28.5-90 Hz -3dB (con ISP-2012)
RESPONSE OF THE SUB-218BS ENCLOSURE (WITH ISP-2022)
2.-ELECTRONIN AND AMPLIFICATION
Musicson serves all the necessary electronics to control the configured
systems in convenient flight cases. The use of Musicson’s signal processors
is absolutely necessary, since they contain the exact filters for an optimal

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performance of each frequency way, control the power applied to each speaker
and take care of preset phase adjustments, in order to result in a correct
phase sum of the different bands.
2.1.- DP-3 SYSTEM
The DP-3 system features three active ways. Its basic configuration is
formed of:
One DP-SB1, one DP-SB2, and one DP-H per channel.
To power the 18” speakers of the DP-SB1 and DP-SB2, we use one channel of
the Musicson HE-1202 professional power amplifier, featuring 1200 W rms per
channel. Both speakers are wired in parallel through the rear panel of the
enclosure.
To power one 12” speaker, we will use one channel of the Musicson P-804
professional amplifier, featuring 800 W rms per channel. The 2”-driver of
the DP-H will be powered through another other channel of this amplifier.
Thus, for a minimum stereo configuration, we will need a flight case that
includes one Musicson HE-1202 and one Musicson P-804 amplifier. Both are
preset at the factory for optimum performance.
The flight case has the connections for signal input and speaker power
output, as well as the mains connector, mounted on a chassis on the front.
On the rear, a second chassis serves exclusively to connect this flight case
to the extension unit, featuring two signal outs for the bass signal and an
additional “Schuko” socket to supply power to this power extension unit.
Furthermore, the signal processor ISP-1014 shall be used together with
the power amplifiers, as they are specifically designed to optimise the
system’s performance. This processor includes an active three-way filter,
configured with 24 dB/oct Linkwitz-Riley filters, with both high pass and
low pass, optimised to improve the frequency response of all three ways. It
also includes a fourth active high pass filter that serves to effectively
and quickly equalise the highest frequencies (from 10 to 20 kHz) of the
high-frequency way.
It also counts on independent power control circuits for each way with
attack and release thresholds adjusted to each frequency margin, avoiding
the “pumping” effect when the system is working at full performance.

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The use of the processor is also important due to the fact that it
includes delay circuitry between the ways that produce an optimisation of
the sum of them all at their crossover frequencies, obtaining a totally
linear response.
The amplification and control electronics of the complete system is built
into one flight case for both channels (stereo).
2.2.- DP-4 SYSTEM
This is an active four-way configuration of the DP-system. It comprises
one SUB-218BS, 2 DP-G and 2 DP-H per channel, as a basic configuration.
To power the two 18” speakers of the SUB-218BS we will use one channel of
the Musicson HE-1202 professional power amplifier, featuring 1200 W rms per
channel. Both will be wired in parallel internally.
To power the four 15” speakers of the DP-G enclosure, two channels of one
of the Musicson P-804 professional power amplifiers, featuring 800 W rms per
channel.
To power two 12” speakers and two 2” drivers on the DP-H enclosure, two
further channels of the Musicson P-804 professional power amplifiers will be
used.
The flight case configuration of this system will be different to the DP-
3, since we will find, for stereo, the power and control electronics for the
sub bass with the ISP-2022 dynamics processor in one flight case and two
further mono flight cases with the configuration described before, that is,
one P-804 for the other three ways, together with the ISP-1014 processor,
especially set up for the DP-4.
The importance of the use of Musicson power amplifiers and processors
8active filters, power controllers internal phase adjustments, etc.) has
been explained in the previous section.
3.- SYSTEM WIRING

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All Musicson DP enclosures have different rear panels with four- and
eight pin Speakon® sockets, serving as signal inputs from the amplifiers or
to link them to further enclosures.
On the flight cases we will find eight-pin Speakon® connectors to the
enclosures, except on the sub bass flight case of the DP-4, where we sill
find four-pin Speakons.
The codes used for the different speaker cabinets are:
1. - SUB-218BS. Pin 1+ to terminal + of one 18"
Pin 1- " " -
Pin 2+ to terminal + of the other 18"
Pin 2- " " - of the other 18"
2. - DP-SB1. Pin 1+ to terminal + of the 18".
Pin 1- to terminal - of the 18".
Further pins connected in parallel with the second 8-pin
Speakon®
3. - DP-SB2. Pin 1+ to terminal + of the 18".
Pin 1- to terminal - of the 18".
Further pins connected in parallel with the second 4-pin
Speakon®
4. - DP-G. Pin 1+ to terminal + of the 15".
Pin 1- to terminal - of the 15".
Further pins connected in parallel with the second 4-pin
Speakon®
5. - DP-H. Pin 1+ to terminal + of the 12".
Pin 1- to terminal - of the 12".
Pin 2+ to terminal + of the 2" driver.
Pin 2- to terminal - of the 2" driver.
It is very important to know that the speaker cabinets have two Speakon®
connectors, one used as the signal input and the other one serves as a
parallel connection to further enclosures of the DP-system. Cables must
always be connected as shown on the rear panels.

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4.-DP SYSTEM SPARE PARTS
Before we start dismantling any acoustic part of a system, we should
check first, where the failure may have originated and located it exactly.

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We first have to make sure that the problem is not due to any element
“previous” to the electronics racked in the flight cases (such as
equalisers, mixing consoles, effects, etc.). If the problem persists, we
should check for the correct functioning of the electronics of the DP-
system: make sure that the processors are “ON” and no “MUTE” button is
pushed. Also make sure that the power amplifiers are “ON” and that they are
receiving signal from the processors. Done this, check the cables for tight
and correct insertion and good condition. If Speakon® connectors are
“locked-in” correctly, they always make good contact. Even so, you might
want to try another cable to ensure correct functioning of these components.
Once all these steps have been undertaken and the problem persists in any
element of the DP-3 or DP-4, you may want to proceed take apart the affected
enclosure, extracting the damaged speaker.
If we are working on an 18” speaker of the SUB-218BS, you must unscrew
the front grille with a Phillips- (cross-) screwdriver before unscrewing the
speaker with an Allen-tool. Now you may take out the speaker.
If we are working on an 18” speaker of a DP-SB1 or DP-SB2, we will first
unscrew the upper (or lower, depending on the model) panel to gain access to
the 18” speaker. You may now unscrew the 8 screws of the speaker with an
Allen-tool and take out the speaker.
In case that a 2” driver of the DP-H is the broken element, first take
apart the upper and lower rigging accessories on the sides of the enclosure,
using an Allen-screwdriver, the screws going through the wood on both sides.
Once unscrewed the accessories, you can take out the grille through slight
bending, since it has no further fixing devices. Once the grille is removed,
you may see the driver and the 12” speaker. The driver is removed by
unscrewing the horn with a Phillips screwdriver, taking out the horn-driver
assembly. Then you’re ready for replacing the membrane.
If we need to work on the 12” speaker, first remove the wooden back
panel. Use a Phillips screwdriver for this purpose. Please remove the panel
with care, since the connector panel is also fixed to it and you might
damage the wiring to the driver and the 12” speaker. Now you remove the
Phillips screws fixing the speaker to the wooden base.
The spare parts for these loudspeakers have the following references:
1. Spare for 18” speaker: Spare for L-18800/8 ohm for DP-3 or DP-4
2. Spare for 15” speaker: Spare for L-15500/8 ohm
3. Spare for 12” speaker: Spare for M-12300/G/8 ohm for DP-H
4. Spare for 2” compression driver: Spare for HT-210/N/8 ohm.

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5.- CONECTIONS AND SETUP
Sine the Musicson DP system is “ready-to-sound” live equipment, we
provide all elements necessary to amplify, control and wire the system the
efficient and fast way.
The material delivered depends on the system configuration chosen by the
user:
5.1.- DP-3 SYSTEM
The basic system that can be configured from the DP-SB1, DP-SB2 and DP-H
enclosures is as follows:
The material delivered by Musicson contains:
- 1 Flight case with 1 Musicson P-804 power amplifier
1 Musicson HE-1202 power amplifier
2 ISP-1014 dynamics processors
Everything conveniently wired
This flight case has a rear panel with XLR sockets for the signal input
and connection to further, equal racks for greater configurations. Power
cord for 220 VAC / 50-60Hz mains is included. It also includes a
supplemental power socket and two 8-pin Speakon® connectors for the speaker
enclosures.
- Cables: 2 cables of 15m with Speakon de 8 pins
2 cables of 1.5m with Speakon de 8 pins

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2 cables of 1.5m with Speakon de 4 pins
- Speaker enclosures: 2 DP-SB1
2 DP-SB2
2 DP-H
- Wiring: The two 15m cables with 8-pin Speakons directly connect the rack
with the 2 DP-SB1 enclosures. The two 1,5m cables with 8-pin Speakons are
used to connect the output of both DP-SB1 to both DP-SB2. Finally, the two
1,5m cables with 4-pin Speakons are used to connect the output of both DP-
SB2 to the inputs of both DP-H.
ATTENTION: In order for the speakers to receive their signal, Speakon®
connectors must be locked, turning them clockwise until the locking device
snaps in.
Auxiliary elements, such as effects, equalisers, mixing consoles, etc.
are not delivered with this live equipment.
To expand the system to double its power, Musicson will deliver a flight
case containing solely a Musicson HE-1202 power amplifier, which will be
connected to the signal outputs of the main rack, including the ISP-1014
signal processors.
The mod. DP-H enclosures will be connected in parallel on both channels,
whereas the power amplification rack will power the bass systems DP-SB1 and
Dp-SB2 from both channels, as shown on the following diagram:

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5.2.- DP-4 SYSTEM
The basic system that can be configured, using the enclosure models SUB-
218BS, DP-G and DP-H is as follows:
The material delivered by Musicson contains:
- 2 Racks, A y B each one containing 1 Musicson P-804power amplifier
1 ISP-1014 dynamics processor
All this conveniently wired.
These flight cases have a rear panel with XLR sockets for the signal
input and connection to further, equal racks for greater configurations.
Power cord for 220 VAC / 50-60Hz mains is included. It also includes a
supplemental power socket and two 8-pin Speakon® connectors for the speaker
enclosures.
- 1 Rack C with 1 Musicson HE-1202 power amplifier.
1 ISP-2022 dynamics processor.

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- Cables: 4 cables of 15m with Speakon of 8 pins
2 cables of 15m with Speakon of 4 pins
4 cables of 1.5m with Speakon of 4 pins
- Speaker enclosures: 2 SUB-218BS
4 DP-G
4 DP-H
- Wiring: The two 15m cables with 4-pin Speakons are connected directly from
the rack to both SUB-218BS.
Two 1,5m cables with 8-pin Speakons are to connect directly Rack A to
both DP-G. Finally, the 1,5m cables with 4-pin Speakons are to be used to
connect the outputs of both DP-G with both DP-H. The same procedure applies
to Rack B and the other DP-Gs and DP-Hs.
Auxiliary equipment, such as effects, equalisers, mixing consoles, etc.
is not delivered with the live equipment.
In order for the DP-4 SYSTEM to work correctly, please make sure that you
link the signal coming from the mixing console (or from a possible effect
rack) to the sub bass rack and from there to both bass-mid-high channel, as
shown on the following diagram:
ATTENTION: In order for the speakers to receive their signal, Speakon®
connectors must be locked, turning them clockwise until the locking device
snaps in.
6.- CONTROL ELECTRONICS
Sine the Musicson DP system is “ready-to-sound” live equipment, we
provide all elements necessary to amplify (power amplifiers), control
(dynamics processors) and wire the system the efficient and fast way.

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The use of these processors: ISP-2022 and ISP-1014 mandatory, not only
for the correct functioning of the acoustic systems, but also the
manipulation, substitution through other processors or active filters by the
user will change these parameters, causing an immediate void on the
guarantee granted by the manufacturer on these systems.
The main characteristics of the processors are the following:
6.1.- ISP-2022
This processor is only used when acquiring a DP-4 configuration.
Its configuration and characteristics turn this processor into a vital
element in obtaining maximum performance of the sub bass enclosures of the
DP-4 system, that is, the SUB-218BS.
It comes installed and wired in a flight case, together with the Musicson
HE-1202 power amplifier.
Its main features are:
Two-way active filter with adjustable crossover frequency.
24 dB / Oct Linkwitz-Riley filters.
High pass and low pass filters for the sub bass way.
High pass filter for the mid-high way.
Variable gain for the low pass output
Adjustable delay between ways.
Phase inversion for the low pass.
All-pass or high-pass selector for the mid-high output.
Active power control circuitry preset by the manufacturer for the SUB-218BS.
- DESCRIPTION OF THE FUNCTIONS.
1. - LOW INVERSION: When this switch is on position “NO”, the mid-high
and low frequency filters are in phase.
At the “YES” position, these two outputs are in opposite phase (180º).
ATTENTION! The phase mentioned is referred to the electrical phase, NOT
the acoustical phase. It is possible that, in order to keep the (acoustic)
phase
of the sub bass way output in-phase, the electrical phase needs to be
inverted for some set-ups.
2. - LOW-HI FREQUENCY: This three-position selector allows selecting the
crossover frequency of both outputs, the values being 90, 120 or 200 Hz. The
switching affects simultaneously both ways.
For the DP-4 system the value to be selected is 90 Hz.