Lab.gruppen PLM Series User Manual

78
Appendix
PLM Series Operation Manual rev 1.1.9
Term Description
Frame ID
An electronic identication ‘label’ which can be given to each Frame in an amplication system. Naming Frames in a large system is
desirable as it simplies identication in the Lake Controller.
Frame Preset
Frame Presets are a class of Presets within the Lake processing system. Up to 100 can be stored in the hardware device, and each holds
the complete conguration of all Modules and the Modules’ internal settings.
Hub
A type of network interface device with multiple Ethernet ports. Data arriving at any port is sent to all others. Hubs have been largely
replaced by Switches.
In-Rush Current
Relevant only to PLM Series devices. When power is applied to a piece of electronic equipment, the initial current taken by the PSU can
be very high as the various capacitors in the circuitry charge up; this is called the in-rush current. In the case of power ampliers, which
contain numerous very large capacitors, the in-rush current can be enough to blow mains breakers. The PLM’s PSU contains circuitry to
control the in-rush current to prevent this.
Input Level
The amplitude of an audio signal at the point where it is applied to the input of the device, or at the input of an intermediate stage within
it. An analog input signal level will be expressed in dBu’s, while a digital input signal level in dBfS (dBs below digital clip level; fS =
full-scale)
IP Address
Every item of equipment connected to an Ethernet network has a unique address called the IP address, so that data gets to the correct
place. IP addresses are written as four groups of three decimal numbers between 0 and 255. In a system consisting of Lake Processors
and a Lake Controller they are assigned and detected automatically.
IP Subnet Mask
IP subnet masks are required in all IP networks. The subnet is determined by the size and type of network being used. For small
networks (less than 254 addresses) a subnet mask of 255.255.255.0 can be used. (A Class C network).
Iso-Float
Iso-Float is Lake’s proprietary method of electronic balancing, which provides a particularly high level of isolation and immunity from
ground loops.
ISVPL
Relevant only to PLM Series devices. ISVPL is an abbreviation for Inter-Sample Voltage Peak Limiter, a proprietary Lab.gruppen
technique for ensuring that voltage at the output terminals of a PLM does not exceed a pre-determined level.
Lake Controller
The Lake Controller is the software application used to control LM 26 Processors, PLM Series and other Lake devices. This software
application provides additional functionality and allows various grouping functions for simultaneous control of multiple Lake Processing-
enabled devices.
Latency
The small but nite delay incurred by audio signals when they are transformed into the digital domain, processed digitally and then
converted back into analog signals. In the Lake system, latency is assured to be constant.
Legacy Lake Device
This term refers to older Lake audio equipment which may form part of an audio system (i.e. Lake Contour Pro 26, Lake Mesa Quad EQ
and the Dolby Lake Processor). The Lake Controller has the capability to control all Lake legacy products.
LimiterMax
LimiterMax is the name given to Lake’s proprietary package of dynamics control which forms part of the Lake Processing system.
Line Driver
An analog audio amplier, usually with zero gain, having very low output impedance and high drive capability. They are used for
transmitting balanced analog audio over very long cables.
Linear Phase Crossover
See FIR Filters
Load Library
Relevant only to PLM Series devices. The Lake Controller includes LoadLibrary, a set of Module les specic to the PLM Series. These
Modules include a database of the electrical characteristics of various popular loudspeakers in addition to the standard Module data. The
PLM uses the load data when verifying and monitoring amplier loads. See Fingerprint, LoadSmart and SpeakerSafe.
Load, equal/unequal
Relevant only to PLM Series devices. The PLM draws different current levels from the AC supply, and thus has different power ratings
according to whether all channels of the amplier are driving into the same load impedance, or if there are different impedances on
different channels.
LoadSmart
Relevant only to PLM Series devices. LoadSmart is a load verication procedure within the PLM which allows the operator to conrm
that each PLM output has the correct quantity and type of speaker connected to it. It is intended to be used pre-performance prior to
running SpeakerSafe.
Loop-Thru
Relevant only to PLM Series devices. This term refers to the Link connectors provided on the PLM for daisy-chaining further ampliers
or other equipment. The use of these to connect further devices is termed a loop-thru.
MAC Address
In addition to an IP address, every device on an Ethernet network has a MAC address. This address is xed at the time of manufacture,
and is effectively the permanent identier of the physical unit. MAC stands for Media Access Control
MaxPeak
Lake’s LimiterMax provides independent dynamics control over signal peaks (MaxPeak) and the average signal level (MaxRMS).
MaxRMS
See MaxPeak.
Module
Module is the term used in the Lake Controller to describe the virtual set of signal processing that routes an audio input to the various
frequency-weighted outputs of a crossover. The processing system within the device allows for two Modules, each of which may be
assigned a range of crossover congurations, input sources, etc.
Module Preset
A class of Preset within the Lake processing system. A Module Preset (Module le) contains all the conguration data and settings for
one Module, and is saved in the Lake Controller software, not in the hardware device.
Ofine
A device on an Ethernet network which is not communicating with the rest of the network either due to a fault or intentionally is said to
be ofine.
Online
A device on an Ethernet network which is fully operational and communicating with the rest of the network is said to be online.
PAL
Relevant only to PLM Series devices. Short for Power Average Limiter, PAL is proprietary Lab.gruppen circuit which provides additional
amplier protection. The PAL ensures that the power drawn by the PSU from the AC mains does not exceed the mains breaker ratings.
Parallel
Two or more e.g. inputs which are wired together so that all inputs are connected to the same source are said to be paralleled. Signal
levels will be reduced if too many inputs are paralleled; in the case of AES3, this may result in a complete loss of audio.
Parameter
Any control function which can be adjusted by the user to one of several different values is termed a parameter. For example, input level,
gain, delay, and limiter threshold are all parameters.

Lab.gruppen PLM Series Specifications

General

DSP	Yes
Network	Ethernet
Connectors	XLR, SpeakON
Cooling	Forced air
Protection Features	Overheat, DC, short circuit
Control Software	Lake Controller