MY GROUP DELAY AUDIBILITY TESTING IS NOW LIVE
Please use the link in the description, below.
I have launched a suite of online tests where you can see if you can distinguish between various levels of group delay that have been added to several different signals (both synthetic and music types).
These tests are quite difficult, even with the synthetic signals. I have added group delay in levels from inaudible to audible, based on the published literature.
PLEASE ENCOURAGE OTHERS TO ALSO TAKE THESE TESTS.
WHY?
ANSWER: The audibility level for group delay in loudspeakers is an important parameter that puts strict limitations on crossover filter design. Once I have a sufficient number of respondents I will analyze and share the data and full details on the adulterations used to generate the test signals. This information will hopefully be useful to the loudspeaker design community at large.
GROUP DELAY TESTING MAIN PAGE:
http://audio.claub.net/GD_testing/GD_Testing_Main_Page.htm
Please use the link in the description, below.
I have launched a suite of online tests where you can see if you can distinguish between various levels of group delay that have been added to several different signals (both synthetic and music types).
These tests are quite difficult, even with the synthetic signals. I have added group delay in levels from inaudible to audible, based on the published literature.
PLEASE ENCOURAGE OTHERS TO ALSO TAKE THESE TESTS.
WHY?
ANSWER: The audibility level for group delay in loudspeakers is an important parameter that puts strict limitations on crossover filter design. Once I have a sufficient number of respondents I will analyze and share the data and full details on the adulterations used to generate the test signals. This information will hopefully be useful to the loudspeaker design community at large.
GROUP DELAY TESTING MAIN PAGE:
http://audio.claub.net/GD_testing/GD_Testing_Main_Page.htm
Interesting test @CharlieLaub . Would like to participatie.
Question: can the sound and music samples be played on my own system, with roon as the controller? So as locally stored files selectable via roon?
Question: can the sound and music samples be played on my own system, with roon as the controller? So as locally stored files selectable via roon?
I listened to the Latin Samba. The timbales played in the first few seconds in the left channel is enough to hear if there is a difference. The problem is I have to try and memorize that while the snippet plays all the way through, then try to compare that sound with the first couple of seconds of one of the samples. Its already screwed up like a lot of these tests are because they don't let the test subject pick a section of the file to loop, then have the ability to instantly switch to another sample's corresponding section to compare with what is briefly held in aural memory. In some ways its a lot like the design of Foobar2000 ABX component. Its designed to favor false negatives.
Foobar2000 ABX lets the user to pick a section of the file and instantly switch from A to B or X to Y.
Indeed it does, but the controls are very sensitive, so as a practical matter I found it very frustrating and essentially unusable.
I made a list of needed improvements a long time ago. Never was able to find anyone who could fix it.
For me at least, usually I would like to pick a small sound segment, maybe two seconds wide, possibly centered around a transient. Then I want to be able to loop that selection without having to push any buttons to restart it each time. Then I want to be able to quicky switch between sample tracks for comparison. I can do that in a program like Reaper quite easily, except it can't be used for this because it shows the waveforms. First task is to easily find a region of interest to focus in on (maybe by clicking on a time line with the mouse to instantly start playback at that point - click around as many times as needed to find a good spot to focus in on), the set the looping limits by clicking on a time line with the mouse. The time line should be zoomable if trying to find a very short segment to compare. For Foobar, it should also be allowed to keep comparing tracks in testing mode (not talking about practice mode at the moment), without being forced to vote every time a track is compared. When ready to vote, the push a button to vote. I think there may have been something else too, but it was awhile ago when I suggested changes.
For me at least, usually I would like to pick a small sound segment, maybe two seconds wide, possibly centered around a transient. Then I want to be able to loop that selection without having to push any buttons to restart it each time. Then I want to be able to quicky switch between sample tracks for comparison. I can do that in a program like Reaper quite easily, except it can't be used for this because it shows the waveforms. First task is to easily find a region of interest to focus in on (maybe by clicking on a time line with the mouse to instantly start playback at that point - click around as many times as needed to find a good spot to focus in on), the set the looping limits by clicking on a time line with the mouse. The time line should be zoomable if trying to find a very short segment to compare. For Foobar, it should also be allowed to keep comparing tracks in testing mode (not talking about practice mode at the moment), without being forced to vote every time a track is compared. When ready to vote, the push a button to vote. I think there may have been something else too, but it was awhile ago when I suggested changes.
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There is a training mode if you don't want to vote. Segment start and end can be set to fraction of seconds.
It is not designed to favor false negatives. It may feel like that when preconceived differences cannot be heard anymore.
It is not designed to favor false negatives. It may feel like that when preconceived differences cannot be heard anymore.
Igreed. I tried all tests, and for the music signals, I wish I could switch versions instantly. Maybe a simple solution would be to stop the current playback everytime a new option is selected. Not exactly what you are suggesting as a solution but might be enough in this webpage.
Congrats to @CharlieLaub for taking the time to build this!
I know what there is. I also know I could sort non-inverting unity gain audio opamp recordings in Reaper. The waveforms were useless, because the differences were too small see (less than a pixel different). But I sort them by ear because operation of the program is user friendly.
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Thank you all for your feedback.
This is the first time I have attempted to set up a test series like this and I was not sure how many would find it interesting or participate, so I tried to be efficient in creating everything. For that reason the interface is rather simple and there is no instant switching as in other ABX tests that you might be familiar with. For now please put up with these quirks,
It is up to the user to decide whether they prefer to use headphones or loudspeakers. I would just like to know which is used, since that might correlate with the success rate.
This is the first time I have attempted to set up a test series like this and I was not sure how many would find it interesting or participate, so I tried to be efficient in creating everything. For that reason the interface is rather simple and there is no instant switching as in other ABX tests that you might be familiar with. For now please put up with these quirks,
It is up to the user to decide whether they prefer to use headphones or loudspeakers. I would just like to know which is used, since that might correlate with the success rate.
very interesting, but think I found a bug in the example?
http://audio.claub.net/GD_testing/test_example/Example_Test.html
Huge differense on option 3 and 6. Hi, hi.
Guess all options should have been the same track?
http://audio.claub.net/GD_testing/test_example/Example_Test.html
Huge differense on option 3 and 6. Hi, hi.
Guess all options should have been the same track?
@torgeirs
That is just the "example". It's not a real test. I only wanted to show people what the form looks like, etc. That is why I used two completely different audio tracks!
The real tests all use the same sounding audio, so it will be much more difficult to tell which has audible differences.
That is just the "example". It's not a real test. I only wanted to show people what the form looks like, etc. That is why I used two completely different audio tracks!
The real tests all use the same sounding audio, so it will be much more difficult to tell which has audible differences.
OK, I expected the same tracks but one tracks to have clearly to high group delay. Then everybody can be trained to find that artifact and what it sounds like.
I thought about that - a "training" session with the "answers" revealed about how much group delay has been added. I would use a different method, e.g. just all-pass GD.
Do you think that would be useful, or would it somehow influence or bias the results of the testing?