Sound Cards that do not work with the MLS measurement method
Sound Cards that have been tested to work with WinMLS
The first measurements walk-through
Measurement 1: Measuring the sound card response
Measurement 2: Measurements requiring input calibration
Preparation: Calibrating the gain steps of your mixer
Combined input calibration example: Calibrating to measure absolute SPL
Individual calibration example: Measuring voltage using an adjustable attenuator
Measurement 3: A simple loudspeaker measurement
Finding delay from Time Data plot type
Delay/Distance from Parameters plot type
Delay from Room Acoustics plot type
Measurement 4: Measure correct delay and frequency response using channel 2 as reference
Measurement 5: Measure correct frequency response and delay using internal reference
Measurement 6: Measure in a "safe" way using loop-back
Loop-back measurement procedure
This happens during a loop-back measurement
What to do if the loop-back synchronization signal not strong enough
Measurement 7: How to measure correct delay time when using the sound card mono microphone input
Measurement 8: Measuring 2 channels simultaneously
Synchronization Loop Connection for 2-channel Measurement
2-channel loop-back for sound cards with one input only
2-channel loop-back for sound cards with two inputs (e.g. line and microphone input)
Synchronization Loop-back Connection for Mono Full Duplex Sound Cards
Measurement 9: Performing a triggered measurement (e.g. balloon burst, or pistol shot)
Measurement 10: Short guide to reverberation time measurements
Post-processing 1: Katz room acoustical parameters round robin (published in JASA)
Post-processing 2: Measurement System Comparison NPL Surrey 2002
Troubleshooting and Known Issues
My sound card does not seem to work correctly?
Why is it impossible to control the input level with the WinMLS mixer?
My frequency response measurements look too flat, why?
Problem after changing preferred sound devices
I can hear feedback, how can it be turned off?
Why does a small change the in volume settings in WinMLS give no effect?
Trouble with WinMLS evaluation period
Double-clicking in the plot will not open the plot type settings dialog
Abnormal termination on shutdown
Plot settings toolbar supports maximum 4 decimals.
Auto-scaling of y-axis maximum value
A tip that will avoid WinMLS to crash
Special case: If two plots are displayed showing the same plot type.
Opening or saving as 24 or 32 bits .wav-files is not possible in this version
How to get started analyzing measurements files (e.g. wav files)?
How to solve a problem with WinMLS?
How to transfer the license from one computer to another computer
I don't like the way the toolbars are positioned, can I do something about it?
How to change the vertical axis from Volt to appear in dB [Pa] or SPL?
How to calibrate the input of the measurement system?
How to calibrate the output of the measurement system?
How to measure using an external source?
Measure with signal from a CD-player
How to make a new wizard or edit an existing wizard?
How to add a new language to the wizard?
How to auto-name when saving measurements?
What does the Windows sound card mixer do when WinMLS is set to control it?
How to get fine resolution on the WinMLS mixer and signal generator slider?
What format is recommended for saving measurement data?
How to convert a measurement file, e.g. of extension .wmb to .wav?
How to improve signal-to-noise ratio for low frequencies?
How to add pre-filtering (emphasis) to the excitation signal?
How to check the background noise spectrum of an impulse response measurement?
What is causing sine sweep artifacts such as pre-ringing?
How to access a measurement from memory?
How to run WinMLS as batch file?
Can a given setup be automatically called using DOS switches?
How to open WinMLS with different setups?
How to read WinMLS files in Matlab?
How to run WinMLS as a function from Matlab?
What is the highest sampling rate available (important for e.g. scale modeling in room acoustics)?
Can multi-channel measurements (>2 input channels) be performed using WinMLS?
How to get the size of the measured impulse response to be a power of two (2N)?
How to write a program for reading the WinMLS .wmb file format
FAQ: Plotting and Post Processing
Plotting - general information
How to set the plot type (e.g. to waterfall) and determine what measurement is to be plotted?
How to access the settings for the plot type?
How to change the vertical axis scaling?
Why is the phase shift not within 360 degrees when measuring with WinMLS?
How to filter a measurement, e.g. using a bandpass filter?
How to change the color of a waterfall plot?
What toolbars are useful when working with a waterfall plot?
What waterfall calculation mode should be used?
If waterfall is plotted, how to read the value of a specific waterfall slice?
How to set the depth of the waterfall plot?
When plotting waterfall, how to select the start point?
The right part of my waterfall look strange, how can I fix this?
How to set the time data window when plotting in frequency domain?
Where are the plot cursor values (x,y) displayed?
Where is the wavelength displayed?
How to change the wavelength unit from meters to feet?
How to save the curve data in the plot?
How to save the plot as a picture?