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What's new...
PureBits.com

 

What's new in version 2.8.0.0 (latest update)
What's new in version 1.2.0.10 to 2.8 (this page)
What's new in version 1.0.2.204 (previous update)

Sample Champion Release 2.5 and above.

  • Some extra options has been added in the "Export Frequency Data as TXT (ASCII) File" section (Settings/File Options).

  • The "Room Acoustics Plugin" now computes and exports all acoustical parameters also in 1/3 Octave bands. This function can be used checking the "Compute and Export 1/3 Octave Acoustical Parameters" checkbox and pressing the "Copy to Clipboard" button in the right upper corner of the plugin.

  • The Impedance Plugin now has a default value of minimum computation frequency of 20 Hz. This value can be lowered down to 5 Hz, if required (for example when a very large woofer with resonance frequency less than 20 Hz is measured).

  • A minor bug in the Quick Settings window has been fixed: now the Weighting Window type can be correctly changed with the Quick Settings window.

 

Sample Champion Release 2.4 and above.
These are the latest updates in Sample Champion. The manual will be updated soon.

  • A custom WAV file can be used as MLS signal. In this way it is possible to pre-filter the MLS signal itself. This could be useful, for example, for performing measurements on tweeters or woofers. This function can be accessed by means of the Settings/General dialog.



    The MLS signal can be filtered by means of the "Filter Banks Plugin" (that works only on Impulse Responses), using the following procedure:
    1- Save the current generated MLS signal (Menu File) as a WAV file
    2- Set (in Settings/File Options dialog) "Load WAV file as.. Impulse Response"
    3- Load the WAV file (now considered as an Impulse Response)
    4- Open the Filter Banks Plugin and filter the I.R. as desired
    5- Save the I.R. as a WAV file and set it as custom MLS signal.

    Now the filtered MLS can be used. Note that the MLS type selected in the Settings MUST have the same order AND TAPS of the custom MLS file, in order to reconstruct correctly the Impulse Response.



Example of Loop-Back Impulse Response, measured
using a band-pass filtered MLS signal

  • The File operations function has been added (Processing/File Operations). Frequency files (.SPE) and Impulse Response files (.IRE) can be summed or averaged.
    If the first line of the comment field of the file has the following content: [W=x] where 0 <= x <= 1, the file is weighted according with the specified value.



    For example [W=0,5] attributes to that file a 0,5 weight. This can be useful for performing loudspeaker sound power measurements or spatial averages of measurements made in different points of a concert hall.
    The File Operations function can be used also for rescaling a frequency or time file by a desired factor (just select a single file, with the desired rescaling factor in the comment field as described above).

    A custom TXT file with a list of Position-Weighting associations can be created by the user. The desired weighting value can then be got by pressing the button "Get Weight from File" in the Save Dialog before saving the file.
    The TXT file must contain a list of weights in this form: [Loudspeaker Position 1]=[1]
    [Loudspeaker Position 2]=[0,85]
    [Loudspeaker Position 3]=[0,80]
    ...


 

  • The Quick Settings dialog has been added (Menu Options/Quick Settings or the button on the control bar). When plugins are opened, the Settings cannot be changed. Using this function some of the settings can be changed also in this case.

  • A bug concerning the saving and loading of WAV files has been fixed.

  • The wallpaper function introduced in version 2.1.1 caused, with some PC configurations, unexpected errors and has been removed.

 

Sample Champion Release 2.1.1 and above.
These are the latest updates in Sample Champion. The manual will be updated soon.

  • Most Recent Used files function has been added (in the bottom of the File menu). If the "Show Open Dialog" option is checked the open dialog is shown when a file in the MRU list is selected, otherwise the file is opened.


  • The capability of recognizing microphone frequency responses (ASCII format) has been added. Now the microphone can be perfectly compensated by means of data furnished by the manufacturer. The range of the microphone compensation has been extended to 48 kHz. The format of the compensation ASCII file must be selected manually.

  • The above figure shows a configuration example for recognizing a microphone compensation file in the following format:

MDF (Microphone Data Format) File
Author=LinearX Systems Inc
Date=May 3,2000 Wed 11:52AM
Model=M53
Serial=105271
dBspl= 94.00
dBm= -14.16
Points=552
Index Freq(Hz) dB Deg <-- 9 comment lines
1 10.15 -13.44 0.00
2 10.31 -12.81 0.00
3 10.46 -12.50 0.00
4 10.62 -12.31 0.00
5 10.78 -12.01 0.00
6 10.94 -11.64 0.00
7 11.11 -11.41 0.00
[...]

 

NOTE: for using spectrum data exported from Sample Champion as Microphone Compensation files, use the following settings:

- FFT Size 1K points
- Export frequency data as a TXT file and use the following exporting options (Settings/File options):


- Use the following Manufacturer Microphone Data File Format options:

  • The Audio Device capability dialog has been improved. Note that in Windows Millenium and in Windows 2000 some frequencies not actually supported could be shown as available (the operating system emulates those frequencies).





  • The exporting format of frequency files has been slightly changed (see Settings/File Options).

  • The output level (Settings/General) can be now set also by entering the desired level in the selector space.

  • Fixed a bug: some post processing operation didn't work when 24 bit resolution input was selected.

  • Fixed a bug: In Vr. 2.0 Amplitude Calibration didn't work. Now fixed.

Sample Champion Release 2.0.0.0 and above.
These are the latest updates in Sample Champion. The manual will be updated soon.

  • 24 bit sampling support.
    Two modes are implemented:
    - 24 bit (1) uses an internal data block align of 3 bytes (actually 24 bit). This mode is suggested for sound cards with A/D and D/A converters with bit resolutions of 18 or 20 bit (for example Pinnacle sound card)
    - 24 bit (2) uses an internal data block align of 4 bytes (actually 32 bit). This mode should work with all 24 bit sound cards
    A function for Audio Hardware Adjustment has been added (see below).

  • Printing feature. The user can select between different resolutions of the data plot.

  • Enhanced bitmap image exporting. A data plot with custom resolution can be generated and saved.




  • Custom colors can be assigned by the user in the Time and Frequency window.



  • The peak position check is now shown also in the remote bar, for a quick check of measurement correctness.

  • The Quality Control function has been added. With this feature upper and lower spectra can be assigned. The computed spectrum is then compared, for each frequency, with the upper and lower limits. If even a single value is outside bounds, a 'BAD' message is wrote, otherwise the result is 'OK'.






    Load Example_QC.spe
    and set Upper_QC.spe and Lower_QC.spe (included in the setup package, Data directory) to see an example

  • A simple Edit Frequency function has been added. It can be useful for creating lower and higher limit spectra for the Quality Control function.



  • Enhanced and more accurate (lockable) Plot Frequency Range control. Optional frequency markers in the low frequency range can now be activated by the user.



  • Enhanced and more accurate (lockable) Plot Time Range control.

  • New Function for wrapping Impulse Response Peak at position X=0, X=100 or X=200.

  • A relative offset in Frequency Overlay can now be selected by the user (adding or subtracting the desired amount in dB). Now spectra measured with different amplitudes can be easily compared.








  • Frequency Plot Amplitude Range user selectable (lockable). Now a Y range of n dB/division can be set by the user and locked.



  • A new directory can now be created in the Save Window.

  • Both channel are now shown in the View Values Window (Time domain data).

  • Sample Champion can now be triggered by means of a command line (from a DOS window or an external program).
    A small utility called RemoteSC is included in the setup package.
    This utility can be called from a command line or from any external program. It allows to start a measurement and save automatically the measured Impulse Response as TXT or WAV file.

    BEFORE calling this utility:
    - Start and leave open Sample Champion that must be ready to start a measurement

    Usage example:

    C:\RemoteDirectory>RemoteSC c:\data\filename.wav -wav

    Starts a measurement cycle and saves the measured Impulse Response as a WAV file

    C:\RemoteDirectory>RemoteSC c:\data\filename.txt -txt

    Starts a measurement cycle and saves the measured Impulse Response as a TXT file

  • How "fine tuning" your Audio Card?
    C
    onnect the input to the output of the soundcard with the loop-back cable as described in the configuration tips page and perform a repeated sequence of measurements, opening scope and impulse response windows.



    Now different things can happen:
    - the impulse response could be still (in time) and clean: in this case the adjustment for this buffer length, channel setting and bit depth does not require any adjustment (leave "0"). Check the cleanness by zooming the impulse amplitude to max by means of the Y zoom slider.
    - the impulse is moving and probably is also not clean (while in the loop-back measure it MUST be clean, if input and output levels are correctly set): increase the length of this buffer (the current setting is marked in blue in the adjustment window) if the impulse moves to the right at every measurement cycle and decrease its length if the impulse moves to the left.
    The same adjustment should be done also when the impulse is still but not clean. Check also ALL scope data to see if something is wrong.

Sample Champion Release 1.2.0.10 and above.
These are the latest updates in Sample Champion (not yet included in the manual):

  • Time domain plugins can be closed from the plugin window and not only from the main program
  • Added a floating menu, activated by clicking the right mouse button on the Sample Champion desktop area
  • Improved accuracy of the level peak meters on the control bar
  • The Information window can be (optionally) opened when a measurement starts
  • New features in the Information window:
    - Estimated measurement remaining time
    - Impulse Response Peak/Noise ratio
    - Automatic control of repeated measurement correctness, checking peak position of each single measure
  • Some improvements in the Load and Save windows
  • The program can be personalized with Name, Address...
  • Added more frequency markers for very low (<50 Hz) and very high (>48Khz) frequencies in frequency analysis windows

Impedance plugin NEW!
Read more in Application Note #16

Sample Champion Release 1.0.2.215 and above.

Frequency Data Overlay



Frequency data (in any view mode) can be overlayed. Up to 5 curves can be simultaneously displayed (current data and 4 overlays).
Frequency data drawing mode must be set to "Draw" (not "Bar"), Y Axis and Y Scale can be freely selected. The X Axis can be Linear or Logarithmic.

The overlay graphs can be set and enabled by clicking the Overlay button in the frequency data window.

This will open the Overlay Frequency Data window.

By clicking the "Set" button, the current plotted spectrum will be set as overlay curve (and saved in the default data directory with the shown name, as standard .SPE file). Also all previously saved .SPE files can be loaded for overlay, provided that they have the same FFT size and sampling frequency of currently displayed spectra. Overlay curves colors can be changed by clicking the "Color" buttons.
Overlay curves settings are saved when the Overlay windows is closed (by clicking again the Overlay button).



Power average mode


Frequency data can now be averaged also in "Power" mode: the magnitude is averaged and the phase information is ignored.
When this option is enabled the phase is set to 0.
The power average mode can be useful when sampling pure tones generated by an external source (asyncronously).
Note that when a spectrum averaged in power mode is saved, the .SPE file is compatible with all other .SPE files (a vector of complex data, positive and negative frequencies), but the Real part of the data is the magnitude of the spectrum while the Imaginary part of the data is 0.



Post processing functions

Some useful post processing functions have been added:

1- Invert I.R.:
This function changes the sign of the current I.R.
2- Reverse I.R.: This function reverses the current I.R. with respect to the middle time point.
3- Normalize I.R. Peak to 1: This function normalizes to 1 the peak value of the current I.R..
4- Find and subtract I.R. Offset: This function finds the continue component and subtracts it from current I.R. This can be useful also when the "Remove offset from sampled data" option (in Settings Advanced) is enabled, because here the operation is performed on the final I.R. (and not on the raw sampled signal before the computation of the Impulse Response).
5- Wrap I.R.: These functions wrap the current I.R. by the selected amount of points (also by fractions of discrete points). This can be useful if the Latency Calibration Time had not been set correctly at measurement time. Note that an I.R. measured with the MLS method has the same period as the MLS, so wrapping doesn't generate discontinuities.
6- Apply Mic. Weighting (and Inverse) to I.R.: This function applies (or removes, if inverse) the current microphone compensation to the current I.R. Note that when Microphone Compensation (Settings/Compensation) is enabled, only the FFT data are compensated). This time data filtering operation requires remarkable computational resources and cannot be performed in real-time. It can be useful when an Impulse Response must be processed by a Time Domain plug-in (Waterfall Plot, Room Acoustics, Enhanced View...).
7- Apply Frequency Weighting (and Inverse) to I.R.: This function has the same behaviour of the above Mic. Weighting function, but compensates the I.R. according to the currently selected frequency weighting (Settings/Compensation).
8- Apply Pink Filtering (and Inverse) to I.R.: This function applies to the Impulse Response a Pink (or inverse Pink) filtering. This operation can be useful when analizying in octave bands measurements performed using an unfiltered MLS signal.

Here is an example:

Flat I.R. Flat Spectrum

This is a simple loop-back measurement and gives a flat power spectrum when its frequency content is analyzed in narrow band. But when an 1/3 octave frequency analysis is required, the graph will look like the following:

Flat 1/3 Octave Spectrum

In the above plot, the effect of 1/3 octave band analysis is correctly shown: every subsequent band is about 1 dB greater than previous one (3 dB in 1/1 octave analysis).

Applying pink filtering to the Impulse Response, the data will look as follows:

Pink Filtered I.R. Pink Filtered Spectrum

Now the 1/3 octave plot will look like the following:

Pink Filtered 1/3 Octave Spectrum

where every band has the same value.
See also Application note#6 about Pink Filtering.



Latency Time Calibration

Now the Auto-Detect latency time calibration feature (Settings/Calibration) is properly working. Just connect audio card input to output and press "Detect Now" and "Go" to perform the calibration. In and Out levels must be correctly set.

Enhanced View plugin NEW!
Read more in Application Note #15

Previous updates

 

 

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