Beta Test: Multitone Loopback Analyzer software

[Sokel]

Could you give these measurements (The RMS values):

View attachment 264596

Like this?

 

[Sokel]

Could you give these measurements (The RMS values):

View attachment 264596

Level (dB)	-15.298	-13.298	-11.298	-9.299	-7.299	-5.298
Fundamental (dB)	-10.9	-8.9	-6.9	-4.9	-2.9	-0.9
Fundamental Freq (Hz)	999.8	999.8	999.8	999.8	999.8	999.8
Level Peak (dB)	-10	-8.7	-6.3	-4.2	-2.1	0
Level RMS (dB)	-15.3	-13.3	-11.3	-9.3	-7.3	-5.3
TD+N (dB)	-98.5	-99.8	-100.6	-101.4	-101	-99.4
IMD (dB)	-101.5	-99.6	-98.1	-97.6	-95.6	-92.9
THD (dB)	-108.9	-107	-105.3	-104.7	-103	-100.3
Noise (dB)	-107.9	-107.5	-107.1	-106.6	-105.8	-104.6
N+D (dB)	-110.8	-110	-108.9	-107.7	-105.3	-101.6
SNR (dB)	100.6	102.6	104	104.4	103.3	100.2
SFDR (dB)	109.7	107.6	105.9	105.4	103.4	100.6
SFDR Freq (Hz)	2999.2	2999.3	2999.2	2999.3	2999.3	2999.3
ENOB (bits)	18.4	18.3	18.1	17.9	17.5	16.9
Delay (ms)	-2.7	-2.7	-2.7	-3	-2.5	-2.2
Drift (ppm)	0	0	0	0	0	0
Jitter Peak (ps)	134.6	96.1	108.7	71.8	46.8	56.2
Jitter RMS (ps)	56.3	43.5	44.2	33.8	28.4	25.9
Harmonics	H2:-117.2dB/+129° H3:-109.7dB/-68° H4:-138.5dB/+128° H5:-130.9dB/+113° H6:-137.6dB/+90°	H2:-116.6dB/+139° H3:-107.6dB/-60° H4:-129.5dB/-70° H5:-126.3dB/+115° H6:-136.5dB/+132°	H2:-116.3dB/+153° H3:-105.9dB/-55° H4:-127.2dB/-74° H5:-120.4dB/+110° H6:-140.4dB/+120°	H2:-116.8dB/-179° H3:-105.4dB/+140° H4:-125.6dB/-59° H5:-116.5dB/-64° H6:-134.4dB/+120°	H2:-114.9dB/-157° H3:-103.4dB/-45° H4:-124.2dB/-59° H5:-121.2dB/+103° H6:-133.9dB/+112°	H2:-112.5dB/-151° H3:-100.6dB/+134° H4:-127.4dB/-47° H5:-120.6dB/-111° H6:-127.7dB/+113°

Edit:
Killer feature this new history add for levels!

 

[Rantapossu]

Like this?

View attachment 264600

Yes.

Do you think that 0.92 mW RMS is right compared to your Peak readings?

 

[Sokel]

Yes.

Do you think that 0.92 mW RMS is right compared to your Peak readings?

So,it should report the peak there?
Makes sense.

 

[Rantapossu]

So,it should report the peak there?
Makes sense.

No, it should report the RMS value on the graph, but is the value 0.92 mW RMS correctly calculated in you opinion vs. the Peak calculations you made earlier?

 

[Sokel]

No, it should report the RMS value on the graph, but is the value 0.92 mW RMS correctly calculated in you opinion vs. the Peak calculations you made earlier?

0.92mW corresponds to 1.17 volts,so it does not seem right,yes.

 

[pkane]

I still can't get my math right...

When watching the spectrum view as a dBFS scale, the graph shows the peak value, right?

View attachment 264587

View attachment 264588

View attachment 264590


And when I calibrate the Voltage, I measure it with my multimeter (Fluke, it should read RMS Voltage) and insert it to the dialog:

View attachment 264591

Now when I measure the spectrum with a Volt scale, it shows the same Voltage I just added:

View attachment 264592

Should this show a peak value and not the RMS value I just added to the Voltage Calibration dialog, just like the dBFS view earlier?


If I calculate the 1,41421356237 * 13,246V = 18,73267284715302 V which is my peak voltage (I think) and add it to the Voltage Calibration dialog, the Spectrum view now shows the peak Voltages and the Level Sweep now shows the same (RMS) Voltages as my Fluke multimeter and shows the same Power levels as I calculate from the readings from my Fluke Voltmeter and my clamp Ampmeter on the dummy load.

If I use the RMS Voltage reading of my Fluke to calibrate the Voltage, Level Sweep shows half of the Power calculated from the Volts and Amps of my meters.

Could you please check the code, if the calibration Voltage should be inserted as a peak Voltage and not as a RMS Voltage?

Thanks, I'll review and do some testing later on today. On the surface it does look like the units are mixed in the calibration dialog.

 

[GXAlan]

What is the expected behavior of "cool down" ? In the preview window it feels like the audio stops 0.2-0.3 seconds before the recording actually stops. Not sure if that is latency between the playback and recording devices being used? Is there a way to have the test tone continue to play after the recording has stopped to ensure that nothing is accidentally truncated?

 

[pkane]

What is the expected behavior of "cool down" ? In the preview window it feels like the audio stops 0.2-0.3 seconds before the recording actually stops. Not sure if that is latency between the playback and recording devices being used? Is there a way to have the test tone continue to play after the recording has stopped to ensure that nothing is accidentally truncated?

Cool down is the period of no output after each measurement, useful when doing sweeps or repeated measurements to let the device cool down (when measuring power amplifiers, for example).

 

[Moto]

I thought you were saying that a one octave discrete notch filter will make a large difference in noise measurement at 10k but not at 1k. That’s not what those results show. What would the analog notch demonstrate?

Paul, sorry for not getting back on this. I ended up traveling. I just tested the cosmos apu into the cosmos adc with 1k and then 10k notch. The thd+n with the 1k notch goes from -112db to -123db when you add the aes17 option in REW.
With the 10k notch the thd+n goes from -83db to -122db when you add the aes17 option.
This was my concern, that using that 1 octave around the fundamental has a bigger effect on noise measurement as you go higher in frequency.
Is there a way to use the calibration files in Multitone as we do in REW?

 

[pkane]

Is there a way to use the calibration files in Multitone as we do in REW?

Yes, just select the file under settings:

 

[Moto]

Yes, just select the file under settings:

View attachment 265120

Same format as REW?

 

[pkane]

Same format as REW?

Yes

 

[Moto]

Yes

Thx. I tried the same test in Multitone and got the same results.

 

[pkane]

Yes, it's time for a new version of Multitone, v1.0.75

https://app.box.com/s/ue7ll9xmvwogst817x2l1xg09opvgy47

A bit of an early pre-release, but I wanted to get your feedback (and a little testing) before I get too far into it.

The main new feature is the addition of a sequenced test plan. I assume that this will be a bit of an advanced feature. But, once a test plan is created and tested, it can be shared with others by simply providing one (.mtp) file that defines all the test parameters. This way others can perform a repeatable set of measurements that can be compared directly to each other.

Test plans can be set up and executed from the new Test menu. Initially it will be empty, with only one choice to '(Add New...)' but will show all available tests once these are created:

Executing an existing test plan is as easy as selecting it from the menu and pressing the Play button:

Stop button is self-explanatory. Play will run through all the measurements in sequence. Step button will execute just the currently selected measurement in the list. View Results will open Windows explorer to the folder where the results were saved after a test. Edit Plan will launch the editor window where you can make configuration adjustments. You can switch between test plans from the drop-down list at the top.

The results of a test are stored into a folder specified when creating or editing the test plan. Currently images for each measurement will be saved into that folder -- this will be expanded to include other results and measurements in the near future.

Add New... from the menu or Edit Plan from the execution window will launch the plan editor that allows you to configure a new (or existing) test plans:

The list of individual measurements that are part of this test plan are on the left. When you have more than one, you can drag any measurement around and drop it to re-order the test.

At the top left, you can select from any of the existing presets that perform a specific type of measurement. That will add a new step to the plan that will be automatically configured to execute that preset. Once you add a step, you can make changes to its configuration on the right. Note that sweeps, and single measurements can be configured here.

You'll notice such settings as FFT size, # of averages, play gain, the type of measurement required, channels to use, etc. All the usual settings and properties used in Multitone measurements will be configurable from here. The one thing that's not stored or configured here are the input and output devices. That's still controlled through the main window in Multitone. Each measurement has its own set of settings and properties and can be changed independently of the others.

One more option in the properties for each measurement is the Repeat Count. This is normally 1, but can be set to 0 to skip this step, or set to more than one to repeat the same measurement multiple times. Results from each of the repeated measurements will be saved.

Add New button will create a new measurement step that is based entirely on current settings in Multitone. You can adjust all of the settings after the new measurement is added.

At the bottom, very few test plan settings for now, but more to come. One is the choice of how to save the result (PNG, JPEG, SVG). You can also configure the name of the folder where the results will be saved.

Prompt to continue will pause between steps in the test plan and ask if you're ready to proceed to the next step. If necessary, this can be used to make hardware adjustments between the steps.

I have plans to add to the type of data and details that will be saved with each test plan, including measurement results, and even to combine multiple results into a single comparison chart... But, first thing's first: let's see if the basic functions work as expected, and are easy to use before I make things even more complicated

 

[Rantapossu]

Yes, it's time for a new version of Multitone, v1.0.75

https://app.box.com/s/ue7ll9xmvwogst817x2l1xg09opvgy47

A bit of an early pre-release, but I wanted to get your feedback (and a little testing) before I get too far into it.

The main new feature is the addition of a sequenced test plan. I assume that this will be a bit of an advanced feature. But, once a test plan is created and tested, it can be shared with others by simply providing one (.mtp) file that defines all the test parameters. This way others can perform a repeatable set of measurements that can be compared directly to each other.

Test plans can be set up and executed from the new Test menu. Initially it will be empty, with only one choice to '(Add New...)' but will show all available tests once these are created:

View attachment 265867


Executing an existing test plan is as easy as selecting it from the menu and pressing the Play button:

View attachment 265870

Stop button is self-explanatory. Play will run through all the measurements in sequence. Step button will execute just the currently selected measurement in the list. View Results will open Windows explorer to the folder where the results were saved after a test. Edit Plan will launch the editor window where you can make configuration adjustments. You can switch between test plans from the drop-down list at the top.

The results of a test are stored into a folder specified when creating or editing the test plan. Currently images for each measurement will be saved into that folder -- this will be expanded to include other results and measurements in the near future.

Add New... from the menu or Edit Plan from the execution window will launch the plan editor that allows you to configure a new (or existing) test plans:
View attachment 265869

The list of individual measurements that are part of this test plan are on the left. When you have more than one, you can drag any measurement around and drop it to re-order the test.

At the top left, you can select from any of the existing presets that perform a specific type of measurement. That will add a new step to the plan that will be automatically configured to execute that preset. Once you add a step, you can make changes to its configuration on the right. Note that sweeps, and single measurements can be configured here.

You'll notice such settings as FFT size, # of averages, play gain, the type of measurement required, channels to use, etc. All the usual settings and properties used in Multitone measurements will be configurable from here. The one thing that's not stored or configured here are the input and output devices. That's still controlled through the main window in Multitone. Each measurement has its own set of settings and properties and can be changed independently of the others.

One more option in the properties for each measurement is the Repeat Count. This is normally 1, but can be set to 0 to skip this step, or set to more than one to repeat the same measurement multiple times. Results from each of the repeated measurements will be saved.

Add New button will create a new measurement step that is based entirely on current settings in Multitone. You can adjust all of the settings after the new measurement is added.

At the bottom, very few test plan settings for now, but more to come. One is the choice of how to save the result (PNG, JPEG, SVG). You can also configure the name of the folder where the results will be saved.

Prompt to continue will pause between steps in the test plan and ask if you're ready to proceed to the next step. If necessary, this can be used to make hardware adjustments between the steps.

I have plans to add to the type of data and details that will be saved with each test plan, including measurement results, and even to combine multiple results into a single comparison chart... But, first thing's first: let's see if the basic functions work as expected, and are easy to use before I make things even more complicated

Thanks, I will test it!

By the way, did you check the RMS / Peak value of the calibration voltage?

 

[pkane]

Thanks, I will test it!

By the way, did you check the RMS / Peak value of the calibration voltage?

I did. It is indeed using RMS as if it's peak value. What I found was that REW has exactly the same behavior (measurement results are the same for the same calibration settings), so for now, I decided to keep it as is.

 

[Sokel]

A-MA-ZING!!!

Thank you!

 

[Rantapossu]

I did. It is indeed using RMS as if it's peak value. What I found was that REW has exactly the same behavior (measurement results are the same for the same calibration settings), so for now, I decided to keep it as is.

Ok.

So, if I want to have a correct values for the level sweep with Watts as a scale, I'll have to do one of the following:

1) Multiply the RMS voltage reading of the multimeter by the square root of two on the calibration dialog.

or

2) Divide the actual load resistance by two on the settings.

Am I correct? I have a fairly powerful amplifier to measure and I would like the results to be correct...

 

[pkane]

Ok.

So, if I want to have a correct values for the level sweep with Watts as a scale, I'll have to do one of the following:

1) Multiply the RMS voltage reading of the multimeter by the square root of two on the calibration dialog.

or

2) Divide the actual load resistance by two on the settings.

Am I correct? I have a fairly powerful amplifier to measure and I would like the results to be correct...

Please update version 1.0.75 if you've already downloaded it. There was a small error in the level sweep X axis calculation (the value was higher than it should be by a fraction due to an RMS calculation that didn't consider the measurement bandwidth limits):

https://app.box.com/s/ue7ll9xmvwogst817x2l1xg09opvgy47

When calibrating voltage for V or W calculations, don't do any fancy calculations. Simply run a 1kHz measurement tone at some reasonable level into the desired load, R. Measure RMS voltage at the output when doing this. Then, when measurement completes enter the measured RMS volts into the calibration window:

Make sure to set the correct load resistance. That's all you need to do to measure power output of the amplifier in a sweep. When doing a single spectrum test instead of a sweep, the two values displayed for the result in the Spectrum plot represent the actual (RMS) power of the amp at that signal level:

This calculation was correct in the previous versions.