Presentation on theme: "LspCAD 6 IJData, Luleå, Sweden"— Presentation transcript:
LspCAD 6 IJData, Luleå, Sweden
LspCAD = Loudspeaker Computer Aided Design A software tool for the construction of loudspeakers. Box modeling with predefined models for the most popular box types. Crossover modeling for both passive and active analog and digital filters. Box models and crossovers can be built in the same design. Design with the objective to both enable fast prototyping and advanced design optimization. Standard and Professional version. Drag and drop interface.
Main window Unlimited number of projects open (limited by system memory) Template project Contains templates for popular building blocks such as closed/bass reflex box, active 2 nd order HP/LP filter. Wizard properties for most of the templates, speeds up design considerably.
Schema window Up to 10 schema pages Two operation modes Edit mode, add, move, delete components, pick components from component tray Simulate mode, change properties (component values) and see result immediately
Schema window, edit mode Passive components Voltage source wire and GND (not exactly passive but located here anyway) Resistor, Capacitor and Inductor, the latter two with ESR, loss and Ri. Complex impedance component, makes it possible to import measured Z of eg. an inductor. Ideal transformer with N1:N2 turns ratio. Loudspeaker symbol for imported SPL and Z. Connector symbol, makes it possible to connect between schema pages. Switch, makes it possible to route signals in different directions or switch on/off filter legs.
Schema window, edit mode Active analog/digital components Ideal OP amplifier G(s) G(z) fast prototyping filter blocks, Analog HP/LP filter up to 8 th order Peak/Notch, allpass, bass/treble boost and 2 nd order HP/LP eq. Matlab directform filter coefficients. Digital Pole/zero and BiQuad. Imported transfer functions. Phase linear FIR filters (up to 4097 filter taps) Sum/add delay and buffer elements for rudimentary digital filters. Models of commercial digital crossovers.
Schema window, edit mode Box cabinet components T/S parameter model Box load and radiation component Port and passive radiator component Horn component Baffle / Near boundary reflection component, makes it possible to simulate baffle diffraction and the impact of the reflections from the closest walls and floor. Other components User note component, add user notes on the schema
Schema window, simulate mode In simulate mode component properties are accessed with either a left or a right click on the mouse. Effect of property changes is seen immediately in the graphs. A number of Store/Recall buttons makes it possible to compare designs fast.
Graphs A number of graphs shows most of the aspects of the design SPL mag and phase and Transfer function Impedance Voltage/Current Group delay and time domain response Off axis simulation Polar plot Graphs can be cloned, this makes it possible to see many graphs at the same time.
Graphs, polar map The polar map displays the off axis reponse as a function of frequency Both vertical and horizontal polar map
Optimizer Optimize SPL, transfer function or impedance Large number of options, slopes, notches/peaks etc. Optimize with penalty function on low load impedance Lock crossover frequencies in a given range. Bandpass boxes can be optimized with a lock on total volume. Undo button makes it possible to revert in case optimization turns out bad.
Snapshot Compare different designs or the same design under different operating conditions
Tolerance analysis Investigate how component variations affect the final result Nominal, min and max data can be exported for pass/fail testing
Crossover emulator Emulate the crossovers without building them. Use line input or WAV file as source Compensates for protection capacitor (recommended for treble units) and cable losses. Emulator impulse response automatically dumped to file for later use in externa convolver such as BruteFIR.
justMLS Measurement program Measure SPL or transfer functions Measure impedance Possible to merge near and far field measurements
KHF tool Combine near and far field measurements. Add contribution from port and drivers for a total response. Apply baffle diffraction to nearfield measurement. Side mounted placement of drivers possible.
Templates Templates are building blocks that are useful in everyday work. Active templates Passive templates Loudspeaker boxes
More features Driver component Off axis simulation, either piston model or imported off axis data Thermal modeling Can link to a baffle / near boundary component for simulation diffraction and reflection effects.
More features Box modeling Based on electrical analog circuit models of the items constituting e.g a bassreflex box (port, box..) Possible to build arbitrary boxes using building blocks To make things simpler, templates for well known box types hide the circuit model (optional).
More features T/S Driver component Thermal modeling Can link to a baffle / near boundary component for simulation diffraction and reflection effects. Bl(x) and Cms(x) nonlinearity modeling, models impact of SPL and Z Can import data from Praxis, CLIO and Klippel Built in component editor