AudioCheck - Internet's largest collection of Sound Tests, Audio Test Tones, and Tone Generators. Online and Free!

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2013.06.01'3:07 - Referral Page : one driver at a time full range sweep

2013.05.30'19:16 - Referral Page : The link at the bottom points to the Pink Noise instead, but when I changed the URL manually, I was able to download the Brown Noise ;)

You're clever ;-) Thanks, the URL has now been fixed!

2013.05.29'18:41 - Referral Page : Hi there, wonderful site. Was wondering if you knew where I could get a set of speakers that I am thinking of branding tested here in the states. Thanks

Pardon my non-nativeness... I am not sure I understand your question. What do you mean by "branding tested"? Please feel free to send an email to me... (stephane@audioch...)

2013.05.27'21:44 - Referral Page : First of all great website! It's really helped me learn to the subtle differences between frequencies and I would definitely donate $ if there was an option to do so. A way this site could be improved in my opinion is if there was another set of freq boosts/notches tests that went by the instrument instead of the whole mix. Ie "which instrument is boosted at what freq by 6 db" or something like that. Obviously you guys would know a better way to go about it but that would be very helpful!

I will think about it, but I am afraid I do not have access to the individual tracks anymore...

2013.05.15'10:40 - Referral Page : Very nice ! Thank you Sir!

2013.05.13'2:37 - Referral Page : My hearing cuts off pretty dramatically at 8k. i did the Hi frequency test with the threshold set to 12k and passed. But I believe I did this mainly by sensing a boost in volume at the low frequencies. So I'm guessing that the total power is held constant? Or is it an illusion on my part?

I checked both audio files using a spectrum analyzer: the lower frequencies are exactly the same (= there is no boost) - only the frequencies above 12 kHz are missing in one of the files. So it must be an illusion, indeed ;-)

I didn't mean to suggest there was a slope. If I take the full spectrum and create a new signal by cutting off all above 12 k, but keep total power the same, then everything below 12 k rises equally. true? Is that happening?

I didn't keep the total power the same: so there is no rise below 12k. So, the audible components should be at the same level. If you can hear a difference in levels, it means that your ears are able to sense something above 12k

2013.05.05'1:58 - Referral Page : My name is Norberto Amaral and I have been invited to give a talk in TEDxLuanda in Luanda, Angola. I would like to use two sound files I got from this website (...) in my presentation and kindly request your permission to do so. This is a non-commercial event and I am NOT earning any money, nor anyone in the event's organization. Thank you for your time, Norberto

Yes, everyone is welcome to use audio files from this website, as long as they make no personal profit using these. Reference or credits to the website are welcome, but not mandatory. I do also appreciate when people drop a little message, as you did. Thanks!

2013.05.04'13:05 - Referral Page : Have you thought about making these tests available as an iOS app? Or is there a test app that you would recommend?

I currently prefer spending time on adding new tests to this website, rather than developing an iOS app. But why not? Let me think about this... ;-)

2013.04.30'17:58 - Referral Page : Great page - cleared some of the stuff up with my system!

2013.04.26'15:36 - Referral Page : with reference to the table on this page surely the top row represents the 8th harmonic of the bottom row etc The bottom row being the fundamental or 1st harmonic the next row up is the 2nd harmonic, the next row the 4th harmonic, finally the 8th harmonic at 8 times the fundamental frequency. other harmonics will occur at 30, 50, 60, 70, Hz etc.
2nd Harmonic can also be known as 1st overtone.

Of course you are totally right. Thanks for pointing my mistake. Being non-native, I completely missed the difference between harmonics and overtone too. Now understood. Page has been updated. All harmonics are now available from the table.

2013.04.25'16:27 - Referral Page : What about front right, front left, and back right, back left?

As soon as I have found a multi-channel audio format compatible with online playback... Any help is welcome...

2013.04.22'0:27 - Referral Page : i can't hear my webpages

2013.04.06'4:09 - Referral Page : in reference to masking effect idea on 2013.02.11, see this graph
http://en.wikipedia.org/wiki/File:Audio_Mask_Graph.png

I'd like to make a blind test, as you suggested. However, there are so many variables to be tested: the masking frequency, the masked frequency and the relative amplitude. I don't want to generate separate files/tests for all possible combinations! And offering one of them is not very useful. Actually, the best tool to test masking is already available to you, in the "Generators" section: Dual Sine Generator. But I keep thinking about a blindtest...

2013.03.31'23:06 - Referral Page : These square/triangle/sawtooth generators have bad aliasing. Generate a square/saw/triangle wave at 15 kHz or so, and you can clearly hear all the aliased harmonics. You can see them on the spectrum too at -40 dBFS or so. Creating the waves through additive synthesis of sine waves up to fs/2 is the easiest way to avoid this. https://gist.github.com/endolith/407991

Square/triangle/sawtooth generators have been designed with the lower frequencies in mind, and perform quite well actually, as benchmarked here. As you found out, only higher frequencies - such as 15 kHz - will suffer from higher aliasing levels. As you know, at those frequencies, only the fundamental should be heard: all other harmonics being higher than half of the Nyquist frequencies, will be filtred out. So, there is no objective reason to work at frequencies higher than 10 kHz with digital square/triangle/sawtooth waveforms: all should play a single sine wave. If this is the test tone you are looking for - a simple sine wave - simply use the sine generator, there will be no aliasing at all.

Actually, I am already using additive synthesis, but this is truly CPU intensive at lower frequencies (with up to thousands harmonics to generate, and more). Remember, this is a free tool offered to the community. Although using additive synthesis *only* was my first idea, I could't implement it online because of the CPU. I had compromize for speed. The compromize is as follow: use additive synthesis to build a wavetable on the fly, then use the wavetable and interpolation to build the desired waveform. This will perform really well at the frequencies where switching to square/triangle/sawtooth waveforms make sense. Unfortunately, at higher frequencies, interpolation generates some aliasing.

2013.03.26'10:34 - Referral Page : Pre-compiled audio test CD's

2013.03.23'20:52 - Referral Page : Really cool test! I got 17Khz !!!!

2013.03.22'4:42 - Referral Page : This site rules. Thank you so much!!

2013.03.17'22:56 - Referral Page : Cool site, thanks. Never would have guessed that English is your second language, didn't notice anything that needed correcting - better than most native English speakers!

2013.03.13'0:11 - Referral Page : Can the Quality test that is the bass shaker damage my headphones? I played it at high volume and could see the drivers under a lot of stress. I had rattling a few times but these are brand new headphones. Thanks

Such as the other tests, the Quality test is meant to be passed with the headphones on your head. You shouldn't look at the drivers...

2013.03.10'12:56 - Referral Page : This is a great test. However to a newbie it took me far too long to understand how to use it. This was probably because I started on a page where I could not hear the difference between the two types. The page should explicitly state something similar to the following in my opinion to make it abundantly clear.

Listen to the reference files of full range and the low-pass filtered noise. If you can hear a difference try the test otherwise pick a lower frequency. For the test, each of the 10 files is either a full range or a low-pass filtered noise. Listen carefully and pick one. You can replay the reference files above as a comparison when making your choices.

The page has been updated with a comment similar to yours. Thanks, your suggestion has been much appreciated!

2013.03.09'5:08 - Referral Page : its greAT

You mean, as great as GREAT? ;-) Thanks!

2013.03.06'14:39 - Referral Page : Timing Difference should be less than 0.5 ms. Find a sample at http://we.tl/IsCJwHJLn6.

Your comment is right. Speed of sound is 340 m/s. The average distance between ears is 0.2 m (20 cm). Time difference is: 0.2/340 = 0.0006 = 0.6 ms. However, the effect seems to work even better with a 10 ms delay (exactly like binoculars increase your stereoscopic vision). Although 0.6 ms is the theoretical maximum value, nothing forces you to use such a value. I couldn't achieve the "hard" panning I was looking for, with a delay as little as half a millisecond. Your sample confirms that the panning is not as strong. I updated the page though, with a comment related to the "absuive use" of those 10 ms.

2013.02.25'14:04 - Referral Page : Congratulations. Best online hearing test I have seen so far

2013.02.25'13:45 - Referral Page : Add test sounds for 4 channel stereo - 2 left, 2 right.

2013.02.16'10:44 - Referral Page : Great site, but unable to download Timing Difference and Low-Pass Filtering wav file under Stereo Perception and Sound Localization.

Fixed! Thanks.

2013.02.11'7:12 - Referral Page : How about some examples of masking effects.. like start out with a 1.2k tone and say 3k tone at same level and then keep running the 1.2k tone up in level, etc. you could do it for serveral frequenceis and would be really cool. thank you for the great site. Tom J. .

Good idea. However, the masking effect is often used on quantification noise (e.g. mp3 encoder), not the frequencies themselves. So, I wonder what kind of test signal I should use...

2013.02.08'14:54 - Referral Page : The test sweep file is encoded in a 192kbps MP3 file which has a low pass filter as well as a shelving filter to remove unnecessary audio data. Depending on the encoder presets, frequencies from 17-22kHz can be severely attenuated or even inaudible which affects the integrity of this test. If the file was recorded in PCM audio or saved as a WAV file, you can use FLAC encoding which is lossless compression(perfect audio data, but smaller file size).

The original file is PCM, and can be downloaded by clicking the download arrow next to the playable icon. Regarding the MP3 files, my encoder settings are such that no critical frequency has been attenuated. I am also using one of the best encoders available (Fraunhofer). Furthermore - when I compress a sound using the MP3 format - I always check the decoded file to ensure that all critical frequencies have been preserved. That's the reason why 192kbps has been used in this case (and 192kbps for a monoral file, that's a 384kbps stereo equivalent!). No reason to worry ;-)

2013.02.07'22:41 - Referral Page : Can you add more notes to perfect pitch test? Like three groups: C scale, chromatic scale and expanded chromatic scale (more than 1 octave)

I will think about it for a next update...

2013.02.06'15:11 - Referral Page : Just perfect, really. You are very professional and because it is easy to use your blind audio test, I learned how to answer correctly. I can answer 10/10 correctly now. Thanks.

Nice! The kind of comments that motivates me keeping the site running ;-)

2013.02.05'21:55 - Referral Page : I was doing your low frequency harmonic test, and I hear 10 hz. you say there is no way I hear it. Is it because of my earphones? Thanks.

This is the purpose of the test. As 10 Hz is truly impossible to hear, it then means that your audio system is producing distortion in the audible range. Maybe your headphones, maybe another piece of your audio equipment.

2013.02.03'19:49 - Referral Page : At what playback level (in Db) is your grey noise calibrated at?

No calibration there, just a dip in the 3k region, and exponential increase in the lower and upper frequencies.

2013.01.21'23:15 - Referral Page : This site would be even nicer if you provided the wav files along some sort of hash like md5 to reduce chances of corruption.

Downloads should be save, and audio file corruption -if it occurs - is plain to hear anyway. If it ever happens, just download the file again.

2012.12.30'0:24 - Referral Page : I think the dynamic range test is broken. The first and second sounds are the same for both NdB and Mute, for all dB levels.

I checked the test again, and for me, the test is working fine. Try the 36dB setting first. If you cannot hear any difference on this one, it could be that your listening environment suffers from a lot of background noise!

2012.12.29'22:38 - Referral Page : I scored 9 out of 10 in the frequency test at 10 k, but it's easy to tell because the filtered version is always louder. This is a bug in the test.

The filtred version is not louder, but the unfiltred version is, because of the added frequencies. If you can hear a loudness difference, you can use this as a cue to pass the blind test. This is not cheating, it really means that the filtred frequency components are still audible to you (otherwise, the perceived intensity would be the same).

2012.12.27'22:20 - Referral Page : left & right test files are the same, please update

Oooops! ...now corrected... Thanks a lot!

2012.12.20'17:46 - Referral Page : This was very interesting. I was able to quantify how bad my hearing is at higher frequencies. Fortunately it is fine between 250 and 1K. Thanks for this resource.

2012.12.19'15:51 - Referral Page : Nice website with fun tests

2012.12.12'21:26 - Referral Page : Would it be possible to release a tool that creates a sweep tone in CSV format?

Thanks for leaving a message on 12.12.12 ;-) Yes, it is possible, but I'd like to understand what could be the use of such text-formatted data file, first. If this functionality can be useful to a wide audience, I can do it. Would you please contact me (Stephane) at

. Thanks!

2012.12.05'23:45 - Referral Page : A surround sound test: Left, Right, Centre, Side Left, Side Right, Back Left, Back Right and LFE channels.

I thought of this, and I tried implement this test using the .wav format. Unfortunately, it seems that such a format is not widely recognized. What receivers expect is a propriatary DTS/Dolby/... format. If someone can share a hint how to implement this, through this website, please contact me (Stephane) at

. Thanks!

2012.11.25'17:15 - Referral Page : Could you test the Quies Confort foam earplugs? I believe the announced -35db nrr is really optimistic especially on low frequencies.

Yes, it is possible. I will contact you by email.

2012.11.02'7:41 - Referral Page : what program was used for mp3 compression (using Fraunhofer it seems)?

Adobe Audition (= Fraunhofer license indeed).

2012.10.20'4:27 - Referral Page : How can i do linear combination of single tone signals in you website.

The combination is linear (sum of the two sine components) but the weights are expressed in decibels. You only need to convert the linear coefficients into decibels: 1 → 0 dBFS, 0.5 → -6 dBFS, 0.25 → -12 dBFS, etc...

2012.10.19'2:32 - Referral Page : Outstanding Page and Tests... Thanks a Bunch DJTunes of California

2012.10.17'12:17 - Referral Page : Very nice!!

2012.10.15'14:35 - Referral Page : Haha, I only started hearing anything at 130Hz on my laptop speakers xD I heard the man's voice fairly clearly though. ( Was the sound not at the same volume as the man's voice..? Maybe this can be changed so people don't have to crank their speakers up possibly..? And every sound is the same volume? Or is that even possible? ) Hmm. And I'm fairly young too, 20..and my speakers are sonicmaster's by ASUS on my ASUS N53SV-A1. Just thought I'd give some feedback on this, thanks for reading. ^_^

Every sound is the same volume, definitely, but the impression will be as you describe: the level seems to get louder as the frequency increases. The explanation is 1/ the frequency response of your speakers 2/ the increased sensitivity of our ears in the midrange frequencies.

2012.09.24'13:34 - Referral Page : Love that binaural part, very nice!

2012.09.21'16:23 - Referral Page : The "blue play button" is not on the the right hand side! It's on the left!!!

As the result of recent change in the icon placement... combined with my dyslexia! Now corrected, thanks ;-)

2012.09.19'23:41 - Referral Page : This is a treasure trove! Well done, I'll keep coming back. Sadly I still suck at the EQ exercises. Cheers, Sigi

I am stuck too, which is even more frustrating being the owner/designer of this site ;-) Thank you for your kind words, Sigi! It helps keeping the site growing.

2012.08.14'10:41 - Referral Page : I got to 16kHz before I heard the noise, but my dog nearly took out my laptop the minute I clicked play.

2012.08.08'7:47 - Referral Page : Hello. Your site is excellent but could you make it HTML5 compliant. And i mean with open source formats and the appropriate tags. Thanks.

According to http://validator.w3.org, the site is compliant with html5 except for the addthis social plug-in. Regarding the open source formats, .ogg is not supported by IE, unfortunately. Instead, we use a combination of .mp3 and .wav, which should play fine in all web browsers, sometimes with the help of Flash though (we use the SoundManager library). As for the appropriate tags, your help/hints are welcome ;-) Please do not hesitate to send us an email. Thank you!

2012.08.07'0:57 - Referral Page : "Hz" as shibboleth, cute

2012.08.02'11:34 - Referral Page : Sometimes in this hobby, it is good to do a reality check!

2012.07.27'08:40 - Referral Page : Literally a treasure trove of information

2012.07.25'23:53 - Referral Page : OK;)

2012.07.25'22:24 - Referral Page : I have one receiver and two sets of speakers. Now I know which I'll use in the new place. Thank you!

2012.07.23'18:15 - Referral Page : Very interesting totally subjective test signals. Thanks!

2012.07.22'07:49 - Referral Page : Audio experts should stay away from this site, as it will prove how good their ears really are!