LspCAD 6

1. LspCAD 6 IJData, Luleå, Sweden http://www.ijdata.com

2. 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.

3. 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 2nd order HP/LP filter. • Wizard properties for most of the templates, speeds up design considerably.

4. 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

5. 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.

6. 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 8th order • Peak/Notch, allpass, bass/treble boost and 2nd 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.

7. 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

8. 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.

9. 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.

10. Graphs, polar map • The polar map displays the off axis reponse as a function of frequency • Both vertical and horizontal polar map

11. 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.

12. Snapshot • Compare different designs or the same design under different operating conditions

13. Tolerance analysis • Investigate how component variations affect the final result • Nominal, min and max data can be exported for pass/fail testing

14. 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.

15. justMLS • Measurement program • Measure SPL or transfer functions • Measure impedance • Possible to merge near and far field measurements

16. 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.

17. Templates • Templates are building blocks that are useful in everyday work. • Active templates • Passive templates • Loudspeaker boxes

18. 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.

19. 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).

20. 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

21. Demo • Get a fully working demo fromhttp://www.ijdata.com

22. Thats all, thanks for watching!