QRDude

Use this free software to assist you in building your QRD diffuser

QRDude saves you having to get out the calculator to work out the well depth for your diffuser. It will design standard and advanced 1D panels, plus 2D panels, in normal and inverse variations.

QRDude in Advanced Mode demonstrating well shifting, manual well width, half-width end wells, and imperial units.

Features of current version - V3.00

• Supports 1D and 2D QRD panels based on prime numbers 3 through to 101
• Calculates inverse panels. 2D inverses in depth-optimised or legacy style
• Auto-calculates well widths based on period width and build depth. May be over-ridden to fine-tune panel width or HF cutoff frequency
• Work in mm, decimal inches or fractional inches to 1/16th inch
• Option to lock build depth and allow design frequency to change as different panels are explored
• Displays period width and build depth (deepest well)
• Displays LF cutoff frequency one octave below lowest diffusion frequency, and displays HF cutoff frequency, where well width equates to half-wavelength
• Advises minimum seating distance based on three times the wavelength of lowest diffusion frequency - V3.00 changed from LF cutoff
• Can display wells as Ratios, Depths, Block heights, or Phase shifts
• Phase wheel shows the phase shifts introduced by the wells at the design frequency
• Visualisation of scattering based on relative well depth either side of fin
• Scorecard screen checks for common problems and lists effective diffusion frequencies
• Supports shifting panel one half well left for symmetrical build when first well is zero-depth
• Advanced mode to find new 1D panels by rotation of phase wheel. Full horizontal shift facility
• Build depth optimiser
• Usable ranges explorer to see changes to bandwidth due to signal angle - new for V3.00
• Lobes screen to see diffusion pattern for multiple 1D panels - new for V3.00
• Export 1D results and scorecard to text file report
• Export 2D cut list and weight estimate to text file report
• Copy pictures to clipboard
• Choice of ways to display picture, to assist when pasting pictures of different panels into a paint program
• Save / Load project. Most recent values and settings restored on restart

QRDude is written in Visual Basic 6 and runs under Windows.
Security information:
Filesize 425,984 bytes     MD5 Hash Code B6BDD68E142D1FEF6F53D29DFB2FD532
If you don't have them installed, you may need to grab the VB6 Runtimes - Windows XP already has them.

2D panel - default settings

Lobes screen for multiple panels

Supporting documentation

An illustrated overview of QRD diffusers can be found on the QRD Technical Overview page - it strongly recommended that you read this first.   (note: heavy graphics)

For detailed instructions on how to use the calculator, see the QRDude User Guide   (note: heavy graphics)

Changes to the software are tracked in the Version notes

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