I have a track that won't fully Analyze

Richard's Avatar


29 Nov, 2018 05:51 AM


I have a FLAC track that won't return a BPM, Key, or Color when I analyze it, although it does return a Danceability. This is from a ripped CD where the other 5 tracks on the CD did return those values. This isn't a commercial CD. It's a CD of a friend's son's band. Any thoughts? I could send you the file, but it is larger than the 10MB limit here. It's 16 MB.


  1. Support Staff 1 Posted by hendrik on 29 Nov, 2018 09:09 AM

    hendrik's Avatar

    Hey Richard,

    please try to attach the file—I think it works even though it says there is a 10mb limit.


  2. 2 Posted by Richard on 29 Nov, 2018 02:23 PM

    Richard's Avatar
  3. Support Staff 3 Posted by hendrik on 30 Nov, 2018 10:51 AM

    hendrik's Avatar

    Hey Richard,

    I have some trouble reproducing the issue. Can you please run the analysis on just that file again and send me a log (Help -> Upload Logs, from with the app).



  4. 4 Posted by Richard on 30 Nov, 2018 01:47 PM

    Richard's Avatar

    I uploaded my log. I re-analyzed once doing just BPM which is my main interest these days. Then I remembered I reported Key and Color didn't populate either, so I re-analyzed again doing BPM, Key, and Color. Same result: those fields didn't populate. I'm attaching here a screen cap showing those tracks in the library. It's a "before" screen cap, but the "after" is identical. The "filled-in" fields on tracks 1-5 (and "danceability" on 6) are from the analysis I did a couple of months ago.

  5. Support Staff 5 Posted by hendrik on 30 Nov, 2018 02:09 PM

    hendrik's Avatar

    For some reason the file is misidentified as 22050.0 Hz file by the Window Media Foundation integration, which is odd, as WMF does not natively support FLAC at all. Any chance you have some sort of FLAC plugin installed?

  6. 6 Posted by Richard on 30 Nov, 2018 02:22 PM

    Richard's Avatar

    No FLAC plug-in. To be honest, this file may not have come from a CD that I ripped. I may have acquired the track directly from my wife's friend. I honestly don't recall. The file is several years old. I know it started out as a home-made recording because, as I said, this is just her son's band performing who-knows-where. I'm content if this track can't analyze, but I reported it since it was odd that it didn't analyze while all the other tracks did.

    I'll attach one of the "good" tracks so you can compare them if you want to.

  7. 7 Posted by Richard on 02 Dec, 2018 05:59 AM

    Richard's Avatar


    I found one other track that doesn't analyze fully.. This track, "Money Blues", is the only track from its CD that didn't analyze. Like the earlier track I reported, it did get a key and a color, but no BPM. I don't know if this is a track I ripped myself or if I downloaded it. It is an mp3 and, other than not being a very good recording, I don't see anything noteworthy about it. When I try to analyze just BPM, beaTunes doesn't issue an error message, but it also doesn't assign a BPM. I'm attaching the file in case you want to look at it, and I'm uploading my log in case you want to look at that, too. This is literally the only track I have that won't get a BPM after multiple attempts, other than the one I reported earlier in this thread, and other than a handful of tracks where I know why no BPM is assigned (the track is too short, or the track is mostly silence, etc.).

    This is a low priority issue for me but I wanted to report it nonetheless.

  8. Support Staff 8 Posted by hendrik on 03 Dec, 2018 09:14 AM

    hendrik's Avatar

    Hey Richard,

    interesting. That last track you sent had me puzzled for a while. Eventually, I figured out that it is a stereo track with the left channel amplitudes values being just the negative of the right channel amplitude values.

    To illustrate:

    • Amplitude values are between -1 and 1, 0 is silence (imagine a loudspeaker membrane pulsing between -1 and 1)
    • Left values may be: -1, 0, 1, 0, -1
    • Right values may be the same: -1, 0, 1, 0, -1 (perfect mono)

    Now imagine this:

    • Left: -1, 0, 1, 0, -1
    • Right: 1, 0, -1, 0, 1

    That kind of signal still sounds perfectly fine, but when you create a mono signal out of it by averaging you get:

    • Mono: 0, 0, 0, 0, 0

    When beaTunes estimates BPM (and most other values), it first computes the mono signal. And as you might have guessed, that's perfect silence, when left is just the negative of right. And that's exactly what's the case in that file. I have no idea how such a thing can happen—perhaps somebody accidentally swapped electric polarity somewhere in production, but it seems quite odd. I have never encountered this before.



  9. 9 Posted by Richard on 03 Dec, 2018 11:18 AM

    Richard's Avatar

    Good detective work! Thanks for taking the time to look into it.

    "That kind of signal still sounds perfectly fine"Actually, compared to the other tracks on the CD, it sounded different, so I slapped "[simulated stereo]" onto the song title. Something obviously got messed up somewhere in production.

          From: hendrik <[email blocked]>
     To: [email blocked]
     Sent: Monday, December 3, 2018 3:14 AM
     Subject: Re: I have a track that won't fully Analyze [Problems #48835]
     #yiv7058272304 pre {width:92%;margin:10px 2%;padding:5px 2%;background:#efefef;border:1px solid #d6d6d6;}#yiv7058272304 blockquote {margin-left:0;padding-left:1em;border-left:5px solid #ccc;}

  10. Support Staff 10 Posted by hendrik on 03 Dec, 2018 11:20 AM

    hendrik's Avatar

    so I slapped "[simulated stereo]" onto the song title.

    Was that supposed to be linked? If so, the link didn't make it. Could you send it again, please?

  11. 11 Posted by Richard on 03 Dec, 2018 11:33 AM

    Richard's Avatar


    I was just replying to your last comment.

    I think I see what happened. I copy/pasted your comment about the track sounding fine, and it brought along some other baggage (the #yiv705... stuff) that I didn't notice.


Reply to this discussion

Internal reply

Formatting help / Preview (switch to plain text) No formatting (switch to Markdown)

Attaching KB article:


Attached Files

You can attach files up to 10MB

If you don't have an account yet, we need to confirm you're human and not a machine trying to post spam.

Keyboard shortcuts


? Show this help
ESC Blurs the current field

Comment Form

r Focus the comment reply box
^ + ↩ Submit the comment

You can use Command ⌘ instead of Control ^ on Mac