Plotting and post-processing overview

Help and explanations

A quick explanation of the menus

An explanation of the dialog boxes

A quick explanation of the toolbars

Remove the toolbars

Where to find the WinMLS documentation?

Microphone amplifier/Phantom power supply

Loudspeaker

Power amplifier

Install and register software

WinMLS license levels

License Transfer

What if the new unlock code does not work?

Loading the setup for your application

Turning off Windows notification sounds

Sound card settings for general sound cards

Step 1 - Select input device

Step 2 - Select output device

Step 3 - Select mixer (volume control)

Let the WinMLS mixer control the Windows mixer

No software mixer

Manufacturer sound card mixer

Number of bits

Specific sound card settings

Line selection

Special case: Using the Windows mixer directly

Multi-channel (>2 channel) measurements

Settings for doing a 1 channel transfer function/impulse response measurement

Calibrating your sound card

Testing your sound card

Making a setup for your sound card

Multi-channel sound card (> 2 input channels)

Example: Measuring M-audio FW 1814

Recommended Sound Cards

High-end measurements

Sound Cards that do not work with the MLS measurement method

Sound Cards that have been tested to work with WinMLS

Explanations

PCI cards

ISA cards

Turtle Beach Monterey/Tahiti

Turtle Beach Fiji/Pinnacle

Turtle Beach Multisound Classic

Creative Soundblaster LIVE External

Sound card settings for Sound Blaster MP3+

Installation

Select mp3+ as the sound card to be used

PCMCIA cards (laptop)

VXPocket (V2) by Digigram

Sound card settings for Digigram Vxpocket

Install the VXpocket

Select VXpocket as the sound card to be used

Connecting the microphone to the VXpocket without using a microphone preamplifier

General information about the Digigram cards (VXpocket, PCXpocket, PCX9 and VX 222)

VXpocket 440 by Digigram

PCXPocket by Digigram

Sound Chips/Laptops

Yamaha AC-XG

Dell Inspiron 3800 (Ess Media 3)

IBM x20 (Crystal Soundfusion)

IBM Thinkpad A22E (Crystal WMD Audio Codec)

Dell Latitude CPt 500GT

NeoMagic MagicMedia 256 CODEC

OPL3-SAx

CS4232 in IBM Thinkpad 380

CS423x in Toshiba Tecra

ESS 1878

ESS Maestro

Measurement 1: Measuring the sound card response

Preparation

Connections

Setting analog input and output level

Setting digital output level

Performing the measurement

Sound card measurement result

Saving the measurement

Changing plot settings

Verifying the sound card measurement

Sound Card Troubleshooting

Saving the settings

Measurement 2: Measurements requiring input calibration

Preparation: Calibrating the gain steps of your mixer

Combined input calibration example: Calibrating to measure absolute SPL

Verify that the calibration is correct

Individual calibration example: Measuring voltage using an adjustable attenuator

Microphone magnitude frequency response correction

Measurement 3: A simple loudspeaker measurement

Preparation

Measurement procedure

Post-processing the measurement

Measuring correct delay time

Finding delay from Time Data plot type

Delay/Distance from Parameters plot type

Delay from Room Acoustics plot type

Delay from Group Delay plot type

Delay from Frequency Response - Spectrum plot type

Measurement 4: Measure correct delay and frequency response using channel 2 as reference

Connect a loop-back to be used as reference

Using channel 2 as reference

Verify that the channels are equal

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

Introduction

Preparation

Preparation for performing a measurement

Results

How plotting works

Save/Export Data in plot

Limit the plotting range, e.g. plotting only in the range 100-5000 Hz

Displaying values in octave bands, octave bands, low-mid-high or broadband

Displaying other room acoustical parameters than reverberation time

Calculating Statistics

Auto-statistics

Display the parameters in a table

More about measuring

4.1 Theory

Measurements using a loudspeaker

Measure using starting pistol, balloon or hand clap

Measuring spatial parameters (LF and IACC)

Post-processing 1: Katz room acoustical parameters round robin (published in JASA)

Reverberation time

EDT

Clarity

Post-processing 2: Measurement System Comparison NPL Surrey 2002

Setting manual start of impulse response

Computing parameters

How to select other parameters

What parameters we included for this comparison

Post-processing 3: How to detect if a measurement wrong?

Setups

Store a backup of your setup

Loading the original setup again

Set WinMLS to start with a specific setup

WinMLS Structure Diagram

WinMLS File Structure Diagram

Troubleshooting

My sound card does not seem to work correctly?

WinMLS mixer and Windows XP

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

Problems with IBM TP 600X laptop running Windows 2000

The plot background colors look strange, why?

Issues

Double-clicking in the plot will not open the plot type settings dialog

Room Acoustics

Abnormal termination on shutdown

Setups toolbar

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

Refresh All

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

What if a setting is changed, how to make sure it is set the same way the next time WinMLS is started?

I don't like the way the toolbars are positioned, can I do something about it?

How to measure with WinMLS?

How to test the input levels?

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 perform calibrate the of mixer output levels?

How to perform calibration of output level?

How to perform "Combined Calibration"?

How to perform "Individual Calibration"?

How to measure using an external source?

Measure with signal from a CD-player

Make a .wav-file and write it to the CD

Alternative: Record the signal to your playback device

Before measuring

Start the measurement

Measure with DAT/MD/CDR as external source

Why use an external source?

How?

Before measuring

Record stimulus on DAT

Start the measurement

Detection of arrival time does not seem to be right, why?

How to make a new wizard or edit an existing wizard?

Guidelines for the WinMLS wizards

Distributing wizards

Step-by-step guide to create a wizard

Prepare a wizard document

Move the figures to the <Pictures> folder

Move the documentation to the <Docs> folder

Create the wizard

Store the setup

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 band limit the excitation signal?

How to generate your own emphasis filter?

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 delete a measurement?

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

Plotting - general information

How to plot a measurement?

How to display two plots simultaneously, e.g. the upper plot displaying frequency response and the lower phase response?

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?

If a setting is changed for the displayed plot-type, how are the curves in the plot updated/refreshed?

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?

How to speed up the plotting?

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?

How to view and manipulate the data of the plotted curves?

How to make calculations, such as subtraction?

How to plot the level of a measurement in octave or one-third-octave bands?

Why can I not see the (one-third)-octave values below 40 Hz?

How to plot the smoothed frequency response at the standard IEC octave or one-third-octave frequencies?

How to plot the smoothed curves more 'graceful'

How to plot spectrum in octave or one-third-octave bands?

How to validate numbers typed in the Plot Toolbar?

How to limit the plotting range, e.g. plotting only in the range 100-5000 Hz?

Plot Chart Settings

How to change the curve type?

How to change the curve style (color, type and width)?

How to change the background color

How to plot figures in black and white only (e.g. for publishing articles)?

How to change the order of curves?

How to erase curves from the plot?

How to choose between plotting several curves and a single curve?

How to display one single curve and set the other curves as invisible?

How to display the legend (a list of the curves that are in the plot)?

How to "turn off" a single curve from the plot without deleting it?

When printing a plot, why is the plot squeezed to the left corner?

How to change the text (and the title, sub title, sub foot, foot) and to store these settings?

How to change the names displayed in the legend?

How to move the legend to an arbitrary position, e.g. inside the plot?

The legend list is filled up, how to solve this?

How to access zoom options, e.g. to turn the mouse zooming on/off ?

How to zoom the plot with the mouse?

Personal versions only: How to move the curves away from the nag screen?

How to scroll the plot using the mouse?

How to turn on and modify gridlines

The left axis labels is wrong, how to change this?

How to set the axis labels format?

How to set the axis labels resolution?

How to set the axis label increment?

How to display the numerical values of the Magnitude Frequency Response Guidelines?

How to find the maximum frequency and its value?

How to add a box displaying the cursor values?

How to delete a text box from a plot?

How to add cursor values and a box with custom text to a plot?

How to add a cursor that follows a curve?

How to make a cursor to follow a curve when there are several curves of the same measurement?

How can curves in the plot remain so that they are there when WinMLS is restarted?

How to print graphs at very high quality

How to remove PASSED/FAILED text from the plot area?

How to remove "Illegal for commercial usage and research" nag screen when upgrading from the personal version

How to remove or add a picture in the plot area?

When using Plot->Add Curve(s)… to add an extra curve and changing the plot type settings, the extra curve gets the same color as the first. How can this be fixed?

How to measure room acoustics?

How are room acoustics parameters presented?

How to set manual start of the impulse response?

How can the Room Acoustics Parameters Grid be copied to a spreadsheet (e.g., Excel)?

How to fix problems with the formatting when pasting room acoustics parameters to Excel?

How to fix problems with the formatting when reading a room acoustics parameters text-file to Excel?

Is the relationship between T30 and T60 linear, so that T60=2*T30?

Strength ISO 3382 Calibration Procedure

Performing calibration measurements

Less accurate calibration

How to detect echoes from a measured impulse response?

Why does the relative axis of the map not always quite follow the yellow time limit line?

Why is it not possible to drag the map to 0 milliseconds

How to make my own map?

How to specify two measurements for computing room acoustics parameters?

Limitations when plotting parameters needing two measurements

How to change the bandwidth, e.g. obtain the reverberation time of the broadband measurement?

How to filter and display the time data (impulse response) for a given frequency?

How to display room acoustics parameters automatically after performing a measurement or opening measurement file(s)?

Batch processing: How to automatically compute room acoustics parameters from several measurements?

How to average room acoustics parameters obtained from several measurements?

Is there a way of automatically sending measurement channel two to the lower plot?

How to change the horizontal axis of the Room Acoustics Parameters plot type?

How is the criterion in the automatic detection of the initial time delay of the impulse response?

Where to find information about the WinMLS setups?

How to measure loudspeaker frequency response?

How to set EQ based on measurements in multiple positions?

How to measure velocity, acceleration and force with WinMLS?

How to measure vibrations with WinMLS?

Measuring with an accelerometer or a velocity/displacement measuring device

Combined calibration

Individual calibration

Measuring with a force hammer

How to measure the frequency response of the measurement system including the microphone and loudspeaker?

How to perform automated measurements with WinMLS, e.g. using a turntable?

A frequency resolution of 1 Hz is desired, how to set the frequency resolution?

How to plot harmonic distortion for a sinusoidal signal?

Power Spectrum plot

Time Data Plot

Measurement Settings

How to measure loudspeaker frequency response and use SPL as vertical axis?

How to set the output signal amplitude to a calibrated value, e.g. 2.83 VoltsRMS?

How to measure the anechoic response of a loudspeaker without doing the measurement in an anechoic chamber?

How to measure loudspeaker directivity?

How to measure levels, such as in octaves and dBA?

How to use WinMLS as a level meter for measuring SPL values in octave, 1/3 octave, dBA?

How to find the level of a measured impulse response (for example in dBA)?

How to find the background noise level of my impulse response measurement?

How to display the level in octave bands?

How to display the level in dBA?

How to display several measurements (e.g., for comparison and for saving the data)?

How to calculate Loudness/Sone (ISO 532B / DIN 45631)?

How to measure speech transmission indices, such as STI and RASTI?

The background noise is "normal"

The background noise is "too high"

The background noise is "normal" but is varying a lot

The background noise is "too low"

I am measuring the speech parameters of an acoustical system (a room) and not a sound system

How to measure loudspeaker impedance?

How to find the level difference of two measurements as function of frequency?

When dividing the same measurement, why is the result not a flat line?

How to find the level difference between stereo speakers?

How to measure at very low frequencies?

Violin Acoustics

Is it possible to process the impulse excitation using the constant Q transform (CAS Journal, Nov.93, p.1-4)?

New

Open...

File types

Supported Files (*.wmb, *.wmt, *.wav, *.tim, *.txt. *.sdf)

WinMLS Binary Files (*.wmb)

Measurement Text Files (*.wmt)

Mono 16-bit WAV Files (*.wav)

Measurement MLSSA files (*.tim)

Text Files (*.txt)

Norsonic Files (*.sdf)

Perform deconvolution

Measurement Tasks…

Close

Save As...

Browser for saving 1-channel measurement

Browser for saving 2-channel Measurement

Browser for saving multi-channel (>2 channels) Measurement

Save All Unsaved...

Advanced Save

Measurement as System Correction File

With Filename `_ActiveMeas_'

Curve(s) as Tolerance Reference(s)

Convert Measurement(s)...

The mixer levels can be "frozen"

WinMLS does not control the Windows mixer

Measurement Selection Toolbar

Clear active measurements from memory

Active measurement

Update both plots with the same measurement

Measurement in lower plot

Measurement Panel Toolbar

Reset Buttons

Measurement Panel Options

List of Curves Toolbar

Erasing curve(s) from the plot

Dragging curves to change the curve order

Change the curve type

Display the curve

Change the curve color

Plot Toolbar

Setting the lower x-axis limit

Setting the upper x-axis limit

Setting the lower y-axis limit

Setting the upper y-axis limit

Auto-scale the plot in all directions

Maximize active plot

Plot Type in Active Plot

Settings for the Active Plot

Active Plot Type Toolbar

Toolbar for time domain plot types

Toolbar for frequency Response

Time Window Toolbar

Lower window limit

Setting the upper window limit

Window length

Window x-axis unit

Time data window type

Display time window in time data plot type

Setups Toolbar

Select a new Measurement Setup

Store Measurement Setup

Select a new Post-processing Setup

Store Post-processing Setup

Standard Toolbar

Status Bar

Status bar during a measurement

Layout Toolbar

3D Toolbar

Load...

Select measurement setup to be loaded

Setup description

Store...

Setup name

Setup description (2)

When loading this setup include

Measurements

Sound card, level and calibration settings

Post-processing setup

Store post-processing setup

Import

Importing setups to a new folder

Load settings when WinMLS is started

Load specified setup

Load the previous settings

Load the last used setup

Ask user what setup to load

Setup-independent options

Freeze toolbar position

Show popup on mouse right-click

Full Menu/All Toolbars

Clear Memory->Active Measurement

Clear Memory->All Measurements

Listen

Calibration…

Input level calibration

Combined calibration

Individual calibration

Output level calibration

Sound card mixer gain steps

Settings...

Sound Card...

Input device

Multi-channel input device

Output device

Mixer (volume control)

Let the WinMLS mixer control the Windows mixer

No software mixer

Manufacturer sound card mixer

Number of bits

Specific sound card settings

Sound card specific

Output volume and EQ (sound card specific)

Save for diagnosis

System Delay…

Ability to measure system delay

Sound card dependent

No, remove system delay

Yes, my sound card is synched

Yes, with loop-back and end-check

Yes, with loop-back, no end-check

Synch. signal settings

Tasks…

When performing or opening a measurement

When performing a measurement

Saving Defaults...

Default file-parameters

Add extra tag to filename

Format

Multi-channel measurement tag

Default title and comments

Wizard Step dialog: Add a new wizard step

Insert title and text

Select image

Select operation

Lock program while wizard is shown

Show this wizard step

Decide how many measurements to perform (if any) before displaying a new wizard step

Move Down wizard step

Erase Curves...

More than one plot displayed

More than one window displayed

Solo Curve

Add Curve(s)

Active measurement curve

Statistics

Overlay

Overlay Settings...

Statistics (auto-update)

Statistics Styles and Colors

More settings

Refresh...

All curves

Refreshing in frequency domain

Active curve

In what plot is refreshing applied?

Auto-Refresh...

Plot Type/ Routing/ Test

Plots in window

Stack plots

Resizing

Limit curve / Test options

Notify user of test result

Generate limit curves

Plotting of limit and error curves

Plot type

Routing

Limit curve

Reference measurement routing

Plot Type Settings: Overview

Plot Type Settings: Active Plot...

Plot Type Settings: General Frequency Domain Settings...

Active measurement settings

Use Time Data processing before computing frequency response

Reference measurement

Perform division

Use unique time window for reference measurement

Select reference measurement

Time window settings for Reference Measurement...

Fourier transform size

Zeropad to lowest possible order of two

Exact same as Time Window

Zeropad to a fixed number of samples

Frequency separation

Various (5)

Averaging, time constant

Plot Type Settings: Time Window...

Measurement name

Window type

Window size

High-frequency window (short)

When new measurement is set as active

Add to window in Time Data plot type

Plot Type Settings: Frequency Response/Spectrum...

Plot Type Settings: Phase Frequency Response/Function...

Horizontal axis (46 (2)

Vertical axis (2)

General Frequency Domain Settings (3)

Remove delay in frequency range

Subtract delay

Plot Type Settings: Group Delay...

Horizontal axis (3)

Vertical axis (3)

General Frequency Domain Settings (4)

Plot Type Settings: Waterfall...

Plot Type Settings: Room Acoustics...

Calculation Settings

Plot layout

Plot Type Settings: Parameter...

Type of parameter to plot

Delay (time of flight)

THD + N (internal sinusoid)

THD (internal sinusoid)

THD + N (external sinusoid)

Level[Fundamental frequency]

Level[# of measurements]

Polarity

Time Data processing

1/3 octave frequency range

Plot Type Settings: Time Data…

Horizontal axis (5)

Vertical axis (5)

Vertical axis scaling

Velocity of sound

Time window

Remove DC-component (0 Hz)

Processing Type

No processing (2)

Integral (Step response)

LowPass/HighPass filter settings

BandPass/BandStop filter settings

Plot Type Settings: Integrated Time Data (Step Response)...

Plot Type Settings: Energy-time Curve

Frequency domain windowing

Unwindowed

Half-Hanning

Blackman-Harris (full)

Filtering using Hamming

Plot Type Settings: Schroeder Curve…

Layout: Axis Labeling

Layout: Text Refreshing...

Display legend inside axis

Include folder in curve name

Include file extension in curve name

Layout: Start/Stop Animation

Layout: Curve Styles and Colors...

Selecting curve color

Selecting curve width and style

Active plot type curve styles

Apply color changes to all windows

Repeat curve styles

Layout: Advanced...

Various (7) (3)

Set cursor to max value on new measurement

Display only name of post-proc. setup as window title

Leave out points from a curve

Limit plotting range

Save chart-file when saving post-processing setup

Associate plot type with curve type and chart-file

Plot type (2)

Curve type

Chart-file

Last Choice again Alt+L

Background noise and speech level influence

No influence

Level given in table below

Influence calculated from calibrated measurement

Reverb times (RT-60)

snr - Signal to noise and edr - effective decay ranges

corr - Correlation

r(m) - Direct sound distance

Strength: Settings...

SPL-level only

Strength - direct sound as reference

Select calibration measurements

Spaciousness

Lateral parameters

Detecting the start of the impulse responses for lateral parameters

LG - Late lateral strength

LF -Lateral fraction

LFC - Lateral Fraction Cosine

Interaural crosscorrelation

Detecting the start of the impulse responses for IACC

User defined: Calculate

User defined: Settings...

Spaciousness 1 (Interaural crosscorrelation)

Spaciousness 2 (lateral parameters)

Level and envelopment (strength)

Strength options

Calculation Options...

New Window

Load Post-processing...

Select post-processing setup

Delete setup

Setup description (3)

Load setup

Store Post-processing As...

Setup name (2)

Setup description (4)

Remark about type approval

Get started measuring airborne sound insulation

Preparation before measuring

Calibrate the input

Prepare for saving intermediate time data results

Sound source power

Microphones and sound source

If your rooms are identical and empty

Room measurement order

Performing the measurements

Level in Sending Room

Measurement settings for traditional standard (ISO 140-4)

Measurement settings for new standard (ISO/WD 18233)

Performing measurement and plotting data

Saving intermediate raw data results

Start a new measurement

Results for sending room

Level in Receiving Room

Saving intermediate raw data results

Background noise in Receiving Room

Reverberation time in Receiving Room

Measure using loudspeaker as source

Measure using pistol/balloon as sound source

Perform the reverberation time measurement

Calculating the final result

Make test report

Adjusting the size of the picture

Avoid typing the same information twice

Print/copy measurement results

Exporting measurement results as text

Export values in plot(s)

Export correction factors in footer

Listening and correcting for measurement errors

Saving the measurement data and plots for later usage

Opening an exported setup zip-file

Remarks on the new proposed ISO/WD 18233 standard

I don't like the sound of the sine sweep. Can a noise-like signal be used instead with the new standard?

How to increase the accuracy of the measurement in cases with very high sound insulation?

Level measurement based on the impulse response