LMS Analyzer

The LMS hardware will run on virtually any legacy, decade-old, crusty computer which provides a full length ISA bus slot. For laptop use, the PAC4 can provide this external slot capability, and interface to the computer using a serial COM port for communication. You'll need to buy the laptop off eBay from a guy named "Gus" who tinkers with stuff in his garage for a living, but it's possible.

The LMS PC card contains a low distortion sine wave oscillator, dual state variable tracking filters, mic preamp, and gated peak/average level detection circuitry. A line level output is provided, along with a balanced line input, and a direct powered microphone input. Any of four locations can be selected for measurement, and external microphone preamps can be supported with level calibration. The basic frequency range of the system spans 10Hz to 100kHz and features a dynamic range of 90dB equivalent to 16bit digital audio.

The high resolution of the system allows up to 200 log-spaced frequency data points to be taken per decade of frequency. This is equivalent to one data point per pixel on the screen! One of the most powerful features of LMS is the dual tracking filters. These filters allow many different types of measurements to be made. The filters can be set for FLAT, LowPass, HighPass, BandPass, and BandReject responses. The accuracy and flexibility of the LMS analyzer rivals systems costing many times more, and is certainly far easier to setup and operate for both novice and experienced users alike.

Overview

LMS is a swept sine wave analyzer for legacy PC computers and consists of an ISA full length PC slot card, connector interface cables, the Windows based application software, and includes a calibrated M31 microphone. LMS can be used for production QC testing of loudspeakers, engineering/development of loudspeakers, and a wide array of general purpose electroacoustic measurements.

The LMS system also includes its own precalibrated M31 measurement microphone. Absolute SPL measurements are made at the touch of the mouse! The small size of the M31 mic is also ideal for near field measurements.

The LMS system provides a vast array of powerful computer based features which are specifically focused on the unique requirements of loudspeaker development and QC production testing. While it operates on a "legacy" platform of decade-old PC architecture (i.e. ISA boards, not compatible with PCI slots) the system is robust.

LMS provides the ability to achieve very high log frequency resolution across many decades of frequency that typical FFTs can't match.

Features

• Color printing through any Windows Printer
• Curve Libraries now hold 99 Curves
• Direct Single/Multiple curve transfer into LEAP-5
• Multi Curve Copy/Paste using Clipboard for transfer
• Advanced Speaker Parameter Derivation
• Simulation of Loudspeaker Model Parameters
• Extensive Graphics Vector and Raster Export
• Manual real-time frequency sweep using mouse
• Maximum sweep resolution now 800 log points
• Macro Editor with syntax highlighting
• MDF Editor for creating/editing any mic file for external mics
• Curve Capture, distill actual curve data from raster images
• Curve Editor, create/modify curves by graphical editing
• Linear, Quadratic, and Cubic Interpolation routines
• Enhanced capabilities for Post Processing Math operations
• Enhanced capabilities for Polar Plot processing and resolution
• Operating Systems: Win98, WinSE, WinME, Win2000, WinXP.

Specifications