Linea Research 88C Series User manual

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LNR series processors 44C/88C Series Amplifier
Linea Research
44C/88C Series Advanced System Amplifier
User Guide
Version 1 (For firmware version 1.218 and above)

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Contents
IMPORTANT SAFETY INSTRUCTIONS ......................................................................................................................4
CONSIGNES DE SÉCURITÉ IMPORTANTES..............................................................................................5
COMPLIANCE ..........................................................................................................................................................8
FOR CUSTOMERS IN EUROPE .............................................................................................................................8
FOR CUSTOMERS IN THE USA.............................................................................................................................9
FOR CUSTOMERS IN THE CANADA .................................................................................................................. 10
Thanks and Unpacking......................................................................................................................................... 11
Unpacking the Linea Research 44/88 C Series Amplifier................................................................................. 11
INSTALLATION INSTRUCTIONS ............................................................................................................................ 12
Mechanical Installation ................................................................................................................................... 12
AC Power Connection...................................................................................................................................... 13
Introduction and Key Features ............................................................................................................................ 14
Introduction..................................................................................................................................................... 14
Key Features ................................................................................................................................................ 14
Audio Connections............................................................................................................................................... 17
Input Connections ........................................................................................................................................... 17
Using unbalanced connections........................................................................................................................ 17
Amplifier Output Connections......................................................................................................................... 18
Load Matching ................................................................................................................................................. 19
Panel Layouts....................................................................................................................................................... 20
Operation............................................................................................................................................................. 22
Starting up the unit.......................................................................................................................................... 22
Overview of Modules, Presets Components and Snapshots........................................................................... 22
Drive Module Presets ...................................................................................................................................... 23
Component Presets ......................................................................................................................................... 23
Factory Module Presets................................................................................................................................... 23
Storing Module Presets ............................................................................................................................... 24
Recalling Module Presets ............................................................................................................................ 24
Recalling Components................................................................................................................................. 24
Input ................................................................................................................................................................ 24
AES3 Inputs.................................................................................................................................................. 24
Networked Audio (Dante) Inputs ................................................................................................................ 24
Automatic Input Selection (Fallover)........................................................................................................... 25
Gain and Polarity ......................................................................................................................................... 25

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Delay............................................................................................................................................................ 25
High Pass Filter ............................................................................................................................................ 25
Parametric Equalisation............................................................................................................................... 26
FIR Shelving EQ ............................................................................................................................................ 26
Parametric Filters ........................................................................................................................................ 26
Routing......................................................................................................................................................... 26
Output ............................................................................................................................................................. 26
Gain and Polarity ......................................................................................................................................... 26
Delay............................................................................................................................................................ 26
High and Low pass Filters ............................................................................................................................ 26
LIR Crossover Filtering ................................................................................................................................. 27
Parametric Equalisation and All-Pass Filters ............................................................................................... 27
Limiters ........................................................................................................................................................ 27
Bridge........................................................................................................................................................... 29
Routing......................................................................................................................................................... 29
Stereo Linking .............................................................................................................................................. 29
IP Address .................................................................................................................................................... 29
Store Snapshot............................................................................................................................................. 30
ECO .............................................................................................................................................................. 30
External Breaker Protection (EBP)................................................................................................................... 30
Ethernet........................................................................................................................................................... 30
Ethernet configurations............................................................................................................................... 30
DHCP............................................................................................................................................................ 31
AUTO-IP ....................................................................................................................................................... 31
Static-IP........................................................................................................................................................ 31
IP Troubleshooting....................................................................................................................................... 31
Snapshots ........................................................................................................................................................ 31
AUX Port A ....................................................................................................................................................... 32
Fault Relay A .................................................................................................................................................... 32
AUX Port B ....................................................................................................................................................... 32
Check Relay B................................................................................................................................................... 32
AUX Port C ....................................................................................................................................................... 32
RS232/ RS485 .................................................................................................................................................. 33
Latency delay................................................................................................................................................... 33
Input/Output Latencies ............................................................................................................................... 33

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Processing Latencies.................................................................................................................................... 33
Overlay Flush ................................................................................................................................................... 34
Protection Systems.......................................................................................................................................... 34
Summary of Protection Indication ...................................................................................................................... 34
Incident Reporting........................................................................................................................................... 35
Performance Logging....................................................................................................................................... 35
Tipi Third Party Interface................................................................................................................................. 36
Processing Block Diagram.................................................................................................................................... 37
EQ and Filter Response Graphs ........................................................................................................................... 38
Technical Specifications....................................................................................................................................... 42
General ............................................................................................................................................................ 42
Audio................................................................................................................................................................ 42
Digital processing............................................................................................................................................. 42
Power Output .................................................................................................................................................. 43
Power supply ................................................................................................................................................... 43
Protection systems .......................................................................................................................................... 43
System protection......................................................................................................................................... 44
Power distribution protection systems ........................................................................................................... 44
Monitoring and logging ................................................................................................................................... 44
OEM Features.................................................................................................................................................. 44
Physical ............................................................................................................................................................ 44
Options ................................................................................................................................................................ 45
IMPORTANT SAFETY INSTRUCTIONS
1Read these instructions.
2Keep these instructions.
3Heed all warnings.
4Follow all instructions.
5Do not use this apparatus near water.
6Clean only with dry cloth.
7Do not block any ventilation openings. Install in accordance with the manufacturer's
instructions.

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8Do not install near any heat sources such as radiators, heat registers, stoves or other
apparatus (including amplifiers) that produce heat.
9Do not defeat the safety purpose of the polarized or grounding type plug. A polarized plug
has two blades with one wider than the other. A grounding type plug had two blades and a
third grounding prong. The wide blade or the third prong are provided for your safety. If the
provided plug does not fit into your outlet, consult an electrician for replacement of the
obsolete outlet.
10 Protect the power cord from being walked on or pinched particularly at plugs, convenience
receptacles and the point where they exit from the apparatus.
11 Only use attachments / accessories specified by the manufacturer.
12 Use only with the cart, tripod, bracket or table specified by the manufacturer, or sold with
the apparatus. When a cart is used, use caution when moving the cart / apparatus
combination to avoid injury from tip-over.
13 Unplug this apparatus during lightning storms or when unused for long periods of time.
14 Refer all servicing to qualified service personnel. Service is required when the apparatus has
been damaged in any way, such as power-supply cord or plug damaged, liquid has been spilled
or objects have fallen into the apparatus, this apparatus has been exposed to rain or
moisture, does not operate normally, or has been dropped.
SAFETY WARNING
Do not remove any covers, loosen any fixings or allow items to enter any aperture.
SAFETY WARNING
The rear of the product may get hot. Avoid direct skin contact during operation and for at least 5
minutes after power has been isolated.
SAFETY WARNING
The product must only be positioned at floor level when operated in a horizontal position.
CONSIGNES DE SÉCURITÉ IMPORTANTES
1. Lisez ces instructions.
2. Conservez ces instructions.
3. Respectez tous les avertissements.
4. Suivez toutes les instructions.
5. Ne pas utiliser cet appareil près de l'eau.
6. Nettoyer uniquement avec un chiffon sec.
7. Ne pas bloquer les ouvertures de ventilation. Installer conformément aux instructions du
fabricant.
8. Ne pas installer près de sources de chaleur telles que radiateurs, registres de chaleur, poêles
ou autres appareils (y compris les amplificateurs) qui produisent de la chaleur.

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9. Ne supprimez pas le dispositif de sécurité de la fiche polarisée ou mise à la terre. Une fiche
polarisée possède deux lames dont l'une est plus large que l'autre. Une prise de terre a eu
deux lames et une troisième broche de terre. La lame large ou la troisième broche sont
fournies pour votre sécurité. Si la fiche fournie ne rentre pas dans votre prise, consultez un
électricien pour remplacer la prise obsolète.
10. Protéger le cordon d'alimentation soit écrasé ou pincé, particulièrement au niveau des fiches,
des prises et le point où ils sortent de l'appareil.
11. Utilisez uniquement les accessoires spécifiés par le fabricant.
12. Utilisez uniquement le chariot, le trépied, le support ou la table spécifiés par le fabricant, ou
vendu avec l'appareil. Quand un chariot est utilisé, soyez prudent lorsque vous déplacez
l'ensemble chariot / appareil afin d'éviter toute blessure en cas de chute.
13. Débranchez cet appareil pendant les orages ou lorsqu'il n'est pas utilisé pendant de longues
périodes de temps.
14. Adressez-vous à un personnel qualifié. Une réparation est requise lorsque l'appareil a été
endommagé de quelque façon que ce soit le cordon d'alimentation ou la fiche endommagé,
du liquide a été renversé ou des objets sont tombés dans l'appareil, cet appareil a été exposé
à la pluie ou à l'humidité, ne fonctionne pas normalement, ou s'il est tombé.
15. Le dispositif ne doit pas être exposé à des gouttes ou des éclaboussures et aucun objet rempli
de liquides, tels que des vases, doit être placé sur l'appareil.
16. Déconnexion permanente de l'alimentation secteur doit être atteint en supprimant le
connecteur du cordon fourni à l'arrière de l'unité. Ce connecteur doit être facilement
utilisable.

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AVERTISSEMENT DE SECURITE
Ne retirez pas les couvercles, ne desserrez pas les fixations et ne laissez aucune pièce s'introduire
dans les ouvertures.
AVERTISSEMENT DE SECURITE
Le radiateur arrière de cet appareil devient chaud. Evitez tout contact direct avec la peau pendant le
fonctionnement et au moins 5 minutes après la mise hors tension de l'appareil.
AVERTISSEMENT DE SECURITE
Le produit ne doit être positionné au niveau du sol lorsqu'il est utilisé en position horizontale.

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COMPLIANCE
FOR CUSTOMERS IN EUROPE
This product complies with both the LVD (electrical safety) 73/23/EEC and EMC (electromagnetic
compatibility) 89/336/EEC directives issues by the commission of the European community.
Compliance with these directives implies conformity with the following European standards:
EN60065 Product safety
EN55103-1 EMC emissions
EN55103-2 EMC immunity
This product is intended for the following electromagnetic environments: E1, E2; E3 & E4.
THIS PRODUCT MUST BE EARTHED. Use only a flexible cable or cord with a green and yellow core
which must be connected to the protective earthing terminal of a suitable mains plug or the earthing
terminal of the installation. The cord must be a maximum of 2m long, have a 2.5mm2CSA, a
300/500V rating and comply with EN50525-2-11 / H05W-F.
THIS PRODUCT IS DESIGNED FOR PERMANENT INSTALLATION. It must be fitted in to a 19” rack
enclosure and not operated unless so installed. The rack enclosure should be open at the front and
back to allow free ventilation and movement of air through the product.

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FOR CUSTOMERS IN THE USA
This product complies with UL60065 7th edition.
THIS PRODUCT MUST BE EARTHED. Use only a flexible cable or cord with a green or green / yellow
core which must be connected to the protective earthing terminal of a suitable mains plug or the
earthing terminal of the installation. The cord must be a maximum of 6’ long, be 14AWG, have a
rating SJ, SJT, SJE or 300/500V H05W-F and be marked VW-1.
THIS PRODUCT IS DESIGNED FOR PERMANENT INSTALLATION. It must be fitted in to a 19” rack
enclosure and not operated unless so installed. The rack enclosure should be open at the front and
back to allow free ventilation and movement of air through the product.
DECLARATION OF CONFORMITY WITH FCC RULES
We, Linea Research Ltd. of 1 Marquis Business Centre, Royston Road, Baldock, Hertfordshire, SG7
6XL, England, declare under our sole responsibility that this family of devices, complies with Part 15
of the FCC Rules. Operation is subject to the following two conditions: (1) this device may not cause
harmful interference, and (2) this device must accept any interference received, including
interference that may cause undesired operation.
FEDERAL COMMUNICATIONS COMMISSION NOTICE
An example of this equipment has been tested and found to comply with the limits for a Class B
digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable
protection against harmful interference in a residential and commercial installation.
This equipment generates, uses, and can radiate radio frequency energy, and if not installed and
used in accordance with the instructions, may cause harmful interference to radio communications.
However, there is no guarantee that interference will not occur in a particular installation. If this
equipment does cause harmful interference to radio or television reception, which can be
determined by turning the equipment off and on, the user is encouraged to try and correct the
interference by one or more of the following measures:
Reorient or relocate the receiving antenna.
Increase the distance between the equipment and the receiver.
Connect the equipment to an outlet on a circuit different from that to which the receiver is
connected.
Consult the dealer or an experienced radio/TV technician for help.
FCC Caution: Any changes or modifications not expressly approved by the party responsible for
compliance could void the user’s authority to operate this equipment.

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FOR CUSTOMERS IN THE CANADA
This product complies with CA /CSA C22.2 No.60065-03
Ce produit est conforme avec CA /CSA C22.2 No.60065-03
THIS PRODUCT MUST BE EARTHED. Use only a flexible cable or cord with a green or green / yellow
core which must be connected to the protective earthing terminal of a suitable mains plug or the
earthing terminal of the installation. The cord must be a maximum of 6’ long, be 14AWG, have a
rating SJ, SJT, SJE or 300/500V H05W-F and be marked VW-1.
CE PRODUIT DOIT ÊTRE MIS À LA TERRE. Utilisez uniquement un câble souple avec un noyau vert ou
vert / jaune qui doit être relié à la borne de terre de connecteur d'alimentation ou la borne de terre
de l'installation. Le cordon doit être un maximum de 6' (2m) de long, 14 AWG (2.5mm2CSA), être
classé SJ, SJT, SJE ou 300/500V H05W-F et être marquée VW-1
THIS PRODUCT IS DESIGNED FOR PERMANENT INSTALLATION. It must be fitted in to a 19” rack
enclosure and not operated unless so installed. The rack enclosure should be open at the front and
back to allow free ventilation and movement of air through the product.
CE PRODUIT EST CONÇU POUR UNE INSTALLATION PERMANENTE. Il doit être installé dans un boîtier
rack 19 ". Le rack devrait être ouvert à l'avant et l'arrière pour permettre la ventilation et le
mouvement d'air libre à travers le produit .
DECLARATION OF CONFORMITY WITH CANADIAN ICES-003
This Class B digital apparatus complies with Canadian ICES-003.
Cet appareil numérique de la classe B est conforme à la norme NMB-003 du Canada.

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Thanks and Unpacking
Thank you for choosing a Linea Research 44/88 C Series Advanced System Amplifier for your application.
Please spare a little time to study the contents of this manual, so that you obtain the best possible
performance from this unit.
All Linea Research products are carefully engineered for world-class performance and reliability.
If you would like further information about this or any other Linea Research product, please contact us. We
look forward to helping you in the near future.
Unpacking the Linea Research 44/88 C Series Amplifier
After unpacking the unit please check carefully for damage. If damage is found, please notify the carrier
concerned at once. You, the consignee, must instigate any claim. Please retain all packaging in case of future
re-shipment.

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INSTALLATION INSTRUCTIONS
Mechanical Installation
The 44/88 C Series Amplifier system is designed to be mounted in a standard 19” rack enclosure.
Where the amplifier is used in a fixed installation, as long as the bottom unit is supported and there are no
gaps between units, it is acceptable to use only the front panel 19” rack holes when fitting it in a standard
rack enclosure. If the amplifier is mounted in a mobile rack it is important that the rear is supported with a
rear rack mounting kit (part number ZA1182). Damage caused by insufficient support is not covered by the
warranty.
431
360
37
482
88

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To prevent damage to the front panel it is recommended that plastic cups or washers are fitted underneath
the rack mounting bolt heads.
It is possible to mount multiple 44/88 C Series amplifiers without ventilation gaps between them but it is
essential that an unobstructed flow of clean air is available from the front of the unit to the rear. It is
important that neither the air intakes on the front of the unit or the exhaust vents at the rear are covered.
Steps must be taken to ensure that hot air does not continually circulate through the amplifiers from the back
of the rack to the front.
The amplifier should never be exposed to rain or moisture during operation or storage. If the unit does come
into contact with moisture, remove the AC power cord immediately and leave it in a dry and warm location to
dry out.
Note that when any equipment is taken from a cold location into a hot humid one, condensation may occur
inside the device. Always allow time for the equipment to attain the same temperature as its surrounding
environment before connecting the AC power cord.
IMPORTANT
It is the responsibility of the user to ensure that dirt, liquids and vapour from theatrical smoke and fog
machines is not ingested by the amplifier. Damage so caused is not covered by the manufacturer’s warranty.
AC Power Connection
The amplifier utilises a 32A Neutrik PowerConTM type locking AC power connector. Use only an AC power cord
with a correctly terminated PowerConTM type connector to make the connection to the mains power supply.
The amplifiers are designed to operate on 50/60 Hz AC power. The power supply sections automatically
configure themselves for either 115V or 230V nominal voltage at turn on. The amplifiers will operate over an
extended range of supply voltages (please refer to the technical specifications).
Note that whilst the amplifier will operate correctly at voltages indicated, the specified output power will only
be achieved when operating with the stated nominal voltages.

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Introduction and Key Features
Introduction
The Linea Research 44/88 C Series Advanced System Amplifier represents current state-of-the-art technology
in several areas. This product is the result of several years of research, from which many advances in switched
mode power technologies and ever finer detail in signal processing have stemmed. Taking advantage of the
latest advances in analogue to digital conversion technologies, the unit achieves performance levels among
the very best that engineering permits.
Below is a list of key features, followed by some information on the major advanced features of the product.
Key Features
-Four/Eight channels of sonically pure Class D amplification
-Very high power density - packs four channels and 20kW or eight channels and 10kW into just 2U of
rack space
-Packed with robust protection and monitoring systems to keep the show going
-External Breaker Protection (EBP) limits the current draw to prevent breakers opening
-Linea Research minimal signal path design
-Class leading sonic performance achieved by the use of state of the art Amplifier technologies and
highly advanced DSP algorithms using Linea Micro Detail (LMD)
-96kHz sampling frequency provides for a nominally flat response beyond 40kHz.
-Simple tamper-proof front panel offers intuitive indication of status
-High speed Ethernet communications supporting DHCP, static-IP and auto-IP and direct connection to
a computer without the need for a router or a switch
-Powerful Drive Module concept, abstraction from device centric to speaker based control
-Innovative Component Presets to allow individual outputs to be used for selected drivers of a
loudspeaker system
-Twelve layers of Parameter Overlays for trouble-free Grouping
-Unique VX limiter providing dynamic control for passive 2-way enclosures
-Unique LIR linear phase crossover shapes giving FIR-like performance without the drawbacks
-Linear phase HF system EQ profiling which provides perfect integration between enclosures
-Innovative excursion control limiter with sliding High Pass Filter; limits only the damaging low
frequencies
-Transducer thermal modelling provides regulation limiters, addressing long term overload
-Overshoot limiter governs amplitude of transient signals retaining average power whilst constraining
peak energy
-Dante audio networking with automatic fallover to Analogue or AES3
-AES3 input

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Drive Modules
The 44/88 C Series processor has a new way of ordering and grouping channels in order to give a more
speaker-based approach to controlling, designing and recalling speaker configurations; these are called Drive
Modules. A Drive Module is the Processing provided by one Input DSP Block, and a number of Output DSP
Blocks, which are associated with one-another by means of routing. For example, if Input DSP Block B is
routed to Outputs 3 and 4, then this is a 2-way Drive Module with Input DSP Block B forming the ‘Master’
control, and Output DSP Blocks 3 and 4 providing the driver-related control. Overall, this forms the processing
typically for one loudspeaker sub-system. The PodWare Drive Module control panel for this sub-system may
then be used for control and monitoring of the associated speaker.
Drive Modules may be included in Module Groups, which use the Parameter Overlay feature in the Device to
achieve trouble-free Grouping in the PodWare application.
The Presets in the Device are Drive-Module centric, and are used to configure individual Drive Modules rather
than the whole device.
Importantly, Drive Modules move the focus away from the processing device, and onto the loudspeaker
systems.
Component Presets allow the Drive Module Presets to be broken apart, allowing any output to be used for
any component within a Drive Module Preset (i.e. any driver in a loudspeaker subsystem).
See Overview of Modules
Overlays
When the Device is used in Modules view in PodWare, this allows the modules to be grouped into Overlay
Groups. These groups allow various Input (master) parameters to be adjusted in all modules in that group,
whist maintaining independent parameter values across each group. This is achieved in the device by
combining the parameters for all the layers for a given section (Gain Delay, EQ etc.). When an Overlay
parameter is active, the Overlay indicator will become illuminated. The combined Gain or Delay etc.
associated with a given section is shown on the module panel in PodWare, within square brackets [ ] under
the Delay and Gain for each input channel. The combined EQ curve is shown in an olive colour. The Input
Mute button in PodWare will flash if an overlay mute is active. An input overlay mute is indicated on the
mute/clip indicator for that channel flashing. See Overlay Flush.
LIR Linear Phase Crossover Filtering
The Device also includes a new type of crossover filtering “Linear Impulse Response” (LIR) crossover filtering,
which results in a Linear Phase crossover that has a constant delay regardless of frequency (unlike other types
of crossover which delay different frequencies to a different extent, thus smearing the arrival time). The LIR
crossover can thus be described as having a flat Group Delay response, and thus entirely free of Group Delay
Distortion.
The shape of the LIR crossover filter is quite similar to a 4th order or 24dB/Oct Linkwitz-Riley filter, and
maintains zero phase difference between the adjacent bands across the crossover region to keep the polar
response rock steady.
FIR Linear Phase Equalisation
The Input High-Shelf Equalisers use Finite Impulse Response (FIR) filtering to produce Linear Phase
equalisation; that is all frequencies are delayed by the same amount, perfectly preserving the transient
response. This can also be important in applications where different amounts of EQ are applied to different

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parts of a speaker cluster, such as to add 'Throw' EQ boost so that parts of cluster which are throwing further
can have HF absorption correction added. If this EQ is not linear phase, then the zones where the speakers
combine may suffer frequency response anomalies.

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Audio Connections
Input Connections
For each input channel there are 3 pins of a Phoenix connector for analogue inputs.
There is also a 6 pin Phoenix connector for one stream (two channels) of AES3 digital audio. The three
terminals marked ‘In’ should be used as the AES3 input to the device. The ‘Link’ terminals are intended to
feed a buffered version of the input on to another device. The ‘Link’ output will still work even when power is
not applied to the device. Note that only two channels of AES3 digital audio are available. The Dante option
permits more channels of Digital Audio inputs.
The HOT, + or ‘in phase’ connection should be made to the + pin of the Phoenix connector.
The COLD, - or ‘out of phase’ connection should be made to the - pin of the Phoenix connector.
The ‘⏚’ Pin of the input connectors is internally connected to the chassis. The shield of the input cable should
always be connected to the ‘⏚’ Pin of the input connector to ensure that EMC performance and regulations
are met.
Pin 2 HOT +
Pin 3 COLD -
Pin 1 Shield
Balanced Input connection
Using unbalanced connections
Please note that the use of unbalanced connections is not recommended, however when connecting the
amplifier to an unbalanced audio source, the signal conductor should be connected to the ‘+’ terminal. The
‘Cold’ conductor or cable screen should be connected to the ‘-‘ terminal with a short connection made
between the ‘-‘ pin and the ‘⏚’ pin.
HOT +
Shield
Unbalanced Input connection

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Amplifier Output Connections
The 44C amplifier is fitted with one SpeakonTM connector per amplifier channel. The appropriate conductor
terminations are shown below and on the rear panel of the unit.
Amplifier output connections –44C
2+
1-
1+
2-
Speaker +
Speaker -
Additionally, the channel 2 output is duplicated on the SpeakonTM connector for amplifier channel 1 for Bi-
Amp wiring. Similarly, the channel 4 output is duplicated on the SpeakonTM connector for amplifier channel 3.
This can be useful for making a connection to two loudspeakers with one 4-core cable (i.e. Bi-Amp).
On the 88C model, all outputs are Bi-Amp; each SpeakonTM connector carries two amplifier outputs –
Channels 1&2, Channels 3&4, Channels 5&6 and Channels 7&8.
Amplifier output connections –88C and Bi Amp
2+
1-
1+
2-
Speaker1 +
Speaker1 -
Speaker2 +
Speaker2 -
In addition, the channel 1 or channel 3 connector (all the SpeakonTM connectors on the 88C model) can also
be used if the pair of amplifier channels is being operated in bridged mode.
Amplifier output connections –Bridge
2+
1-
1+
2-
Speaker +
Speaker -
More than one speaker can be connected to each channel provided the total impedance per channel is not
less than 2 ohms. In bridged mode the minimum total impedance should not be less than 4 ohms.

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Load Matching
Each output of the device can be optimised to drive either a low impedance load (e.g. 2, 4 or 8 Ohms), or a
Constant Voltage (C.V.) using the Load parameter in the Output menu. There are several C.V. settings (25V,
70V and 100V Line) which determine the maximum RMS voltage that the amplifier will produce. Select the
one which is appropriate for the installation. A number of low impedance settings (depending on the model)
are also available. Although it is not critical that this setting matches the impedance of the connected load,
this will maximise the power that is available for the load.

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Panel Layouts
3
2 4 5 6
1
(The 44C is illustrated. The 88C is similar, but with more input and output indicators)
Power Switch- Applies mains power to the device. If the device has entered Sleep mode, it may be woken up
again either from the PodWare application, or by switching this switch off, then on again.
Status Indicators- The “OVERLAY” indicator shows when there are parameters active on a group layer, which
the user cannot access through the front panel of the device (see Overlay Flush). The “NETAUDIO” indicator
shows that a networked digital audio card is installed and routed (Such as Dante™). The “ONLINE” indicator
has three states: Off –the unit is offline and not connected to a computer or network. Flashing- the unit is
searching for an IP address; if the unit does not find an IP address the unit will assign itself an IP address
automatically and the indicator will stop flashing. On- the unit is online and connected with software. IP
settings can be viewed or changed within the <UTILITY> pages. The “AES3 IN” indicator illuminates when one
or more of the inputs is using an AES3 source.
Input Signal Indicators- A set of indicators show “Sig”, “-20”, “-10” and “Clip (mute)” for each of the DSP
inputs “A” “B” “C” “D”(and “E” “F” “G” “H”on the 88C). The signal present Indicators operate at
approximately –40 dBu. The Clip/mute Indicators warn the user of input overload and operate at 1dB before
clip. This indicator also shows a muted input. The indicators in the input section are sometimes used to show
progress of an action (a clockwise rotating wheel pattern), or confirmation of an action (e.g. an expanding
square to confirm snapshot recall), or an error condition (‘Motorway’hazard flashing).
Bridge Indicator- This will illuminate when the channel pair is in Bridge mode. The controls for the left channel
of the pair will determine the settings. See Bridge Mode
Amplifier Indicator- This indicates when the amplifier protection systems are reducing the gain to keep the
parameters of the amplifier within specification, or when that the channel is clipping.
Driver Indicator- This indicates a signal 6dB higher than the limiter threshold, or when the threshold of the
excursion limiter has been exceeded, or when the thermal limiter is active. Please note that because of the
long release time of the thermal limiter, this indicator may remain illuminated for several seconds after signal
on that channel is reduced.
Limiter Indicators- The output indicators shows the status of the limiter and output level. The <SIG> indicator
shows when a signal is present on the output. The second indicator <-6dB> shows that the signal has reached
6dB below the limiter threshold. The third <LIMIT> indicator indicates that the threshold of that output
channel has been reached. The indicators in the output section are sometimes used to show progress of an
action (by illuminating progressively more indicators), or confirmation of an action (e.g. illuminating a number
of indicators equalling the number of a Snapshot being recalled).