Lab.gruppen PLM series Operation Manual page 84

Appendix
Term
Frame ID
Frame Preset
Hub
In-Rush Current
Input Level
IP Address
IP Subnet Mask
Iso-Float
ISVPL
Lake Controller
Latency
Legacy Lake Device
LimiterMax
Line Driver
Linear Phase Crossover
Load Library
Load, equal/unequal
LoadSmart
Loop-Thru
MAC Address
MaxPeak
MaxRMS
Module
Module Preset
Offline
Online
PAL
Parallel
Parameter
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PLM Series Operation Manual rev 1.1.9
Description
An electronic identification 'label' which can be given to each Frame in an amplification system. Naming Frames in a large system is
desirable as it simplifies identification in the Lake Controller.
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 configuration of all Modules and the Modules' internal settings.
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.
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 amplifiers, 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.
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)
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 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 is Lake's proprietary method of electronic balancing, which provides a particularly high level of isolation and immunity from
ground loops.
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.
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.
The small but finite 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.
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 is the name given to Lake's proprietary package of dynamics control which forms part of the Lake Processing system.
An analog audio amplifier, 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.
See FIR Filters
Relevant only to PLM Series devices. The Lake Controller includes LoadLibrary, a set of Module files specific 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 amplifier loads. See Fingerprint, LoadSmart and SpeakerSafe.
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 amplifier are driving into the same load impedance, or if there are different impedances on
different channels.
Relevant only to PLM Series devices. LoadSmart is a load verification procedure within the PLM which allows the operator to confirm
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.
Relevant only to PLM Series devices. This term refers to the Link connectors provided on the PLM for daisy-chaining further amplifiers
or other equipment. The use of these to connect further devices is termed a loop-thru.
In addition to an IP address, every device on an Ethernet network has a MAC address. This address is fixed at the time of manufacture,
and is effectively the permanent identifier of the physical unit. MAC stands for Media Access Control
Lake's LimiterMax provides independent dynamics control over signal peaks (MaxPeak) and the average signal level (MaxRMS).
See MaxPeak.
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 configurations, input sources, etc.
A class of Preset within the Lake processing system. A Module Preset (Module file) contains all the configuration data and settings for
one Module, and is saved in the Lake Controller software, not in the hardware device.
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 offline.
A device on an Ethernet network which is fully operational and communicating with the rest of the network is said to be online.
Relevant only to PLM Series devices. Short for Power Average Limiter, PAL is proprietary Lab.gruppen circuit which provides additional
amplifier protection. The PAL ensures that the power drawn by the PSU from the AC mains does not exceed the mains breaker ratings.
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.
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.