Chandos and gapless playback

[mathias broucek]

Chandos's website states that: "Please Note: On Mp3 format an unavoidable click may be heard on segue track breaks, to avoid this issue please select lossless"

For this reason I've not purchased any Chandos mp3 where this would clearly be an issue. However I had had problems with gapless playback from Chandos MP3s from emusic and AACs from iTunes.

I have two questions:

1. How come other providers manage to provide adequate gapless playback on MP3s? (For example I downloaded the Kempe Lohengrin cheaply from Amazon and that has no gaps.)
2. How come Chandos - one of the better record companies - sees fit to even SELL MP3s of music for which a lack of gapless would be a disaster? They do give fair warning but for some albums the lack of gapless would surely make them of questionable "merchandisable quality".

Any thoughts? (Other than - "you should buy the CD" which is usually my preferred route.)

[Eine Alpensinfonie]

Chandos's website states that: "Please Note: On Mp3 format an unavoidable click may be heard on segue track breaks, to avoid this issue please select lossless"

For this reason I've not purchased any Chandos mp3 where this would clearly be an issue. However I had had problems with gapless playback from Chandos MP3s from emusic and AACs from iTunes.

I have two questions:

1. How come other providers manage to provide adequate gapless playback on MP3s? (For example I downloaded the Kempe Lohengrin cheaply from Amazon and that has no gaps.)
2. How come Chandos - one of the better record companies - sees fit to even SELL MP3s of music for which a lack of gapless would be a disaster? They do give fair warning but for some albums the lack of gapless would surely make them of questionable "merchandisable quality".

Any thoughts? (Other than - "you should buy the CD" which is usually my preferred route.)

This is an incredibly annoying feature of many downloads. Even when I try to make gapless CDs from downloads, there is usually a very small gap. At least 2 of my half-dozen Alpine Symphony downloads have this problem, the most recent being the Collins Classics LSO/Burgos reissue (download only). I would always buy the CD whenever there's a choice.

[johnb]

It seems to be something inherent in the mp3 format. This is from Wikipedia:

Lossy audio compression schemes that are based on overlapping time/frequency transforms add a small amount of padding silence to the beginning and end of each track. These silences increase the playtime of the compressed audio data.[1] If not trimmed off upon playback, the two silences played consecutively over a track boundary will appear as a pause in the original audio content. Lossless formats are not prone to this problem.

For some audio formats (e.g. Ogg Vorbis), where the start and end are precisely defined, the padding is implicitly trimmed off in the decoding process. Other formats may require extra metadata for the player to achieve the same. The popular MP3 format defines no way to record the amount of delay or padding for later removal.[notes 1] Also, the encoder delay may vary from encoder to encoder, making automatic removal difficult.[2] Even if two tracks are decompressed and merged into a single track, a pause will usually remain between them.

[PJPJ]

This is an incredibly annoying feature of many downloads. Even when I try to make gapless CDs from downloads, there is usually a very small gap. At least 2 of my half-dozen Alpine Symphony downloads have this problem, the most recent being the Collins Classics LSO/Burgos reissue (download only). I would always buy the CD whenever there's a choice.

The very few times I have had this problem (I avoid mp3) I have joined the mp3 files together and removed the gaps.

You can do this in mp3directcut* without having to re-code, it's slightly fiddly, or........

convert the mp3s to wav and copy and paste into a wav editor, remove the gaps and save the whole as a single lossless file.


* open each mp3 in mp3directcut, and copy and paste each of the second, third etc windows in turn into the first window, building up the whole piece of music.

[If you need separate tracks you'll achieve this using a cue-sheet. If you know how to use a cue sheet, you will have known how to join the files together!]

[mathias broucek]

The very few times I have had this problem (I avoid mp3) I have joined the mp3 files together and removed the gaps.

You can do this in mp3directcut* without having to re-code, it's slightly fiddly, or........

convert the mp3s to wav and copy and paste into a wav editor, remove the gaps and save the whole as a single lossless file.


* open each mp3 in mp3directcut, and copy and paste each of the second, third etc windows in turn into the first window, building up the whole piece of music.

[If you need separate tracks you'll achieve this using a cue-sheet. If you know how to use a cue sheet, you will have known how to join the files together!]

Thanks PJPJ but if it's that easy how come Chandos can't manage it? (They'd have to edit the track names but most people would rather have gapless, wouldn't they?)

[johnb]

mb, please read the quote I posted from Wikipedia. It is a problem with the mp3 format, not with Chandos.

PJPJ said he joined the tracks together - a different situation. Though, you could argue that Chandos should offer the option to download the whole CD as one track, together with a cue file, but I would guess that would only appeal to a minority.

[Don Petter]

Though, you could argue that Chandos should offer the option to download the whole CD as one track, together with a cue file, but I would guess that would only appeal to a minority.

That would be the simplest solution for the user, and is just what Pristine does (as well as offering an actual CD).

[richardfinegold]

That would be the simplest solution for the user, and is just what Pristine does (as well as offering an actual CD).

Does Chandos only offer these recordings as downloads, or do they offer a CD as well?

[mathias broucek]

I think we're missing the point. I have several MP3 recordings where gapless playback works just fine without joining the tracks so it MUST be possible.

[johnb]

mb, out of curiosity, from where did you download your Kempe's Lohengrin?

[Dave2002]

mb, please read the quote I posted from Wikipedia. It is a problem with the mp3 format, not with Chandos.

Maybe, but only up to a point. If this is a problem with mp3 files, then Chandos could release music on mp3 with only continuous chunks of music.
This could result in a loss of some convenience in some situations, such as a set of short variations, but would at least mean that the music could be enjoyed without hiccups.
They could do that - they don't have to assume a 1-1 equivalence between CD and mp3 tracks.

We don't normally worry about the lengths of gaps between movements etc., where there is "silence" so hopefully this approach would cover more than 99% of cases, but would give companies like Chandos more work to do, which perhaps they haven't wanted to do.

[mathias broucek]

mb, out of curiosity, from where did you download your Kempe's Lohengrin?

From Amazon. I also have some (but not all) Passionato downloads that work just fine gaplessly.

[PJPJ]

http://en.wikipedia.org/wiki/Gapless_playback

Apologies if this link has already been posted - it mentions hardware and software causes and solutions.

[johnb]

PJPJ,

That was the source of the quote I posted earlier.

mb,

The interesting thing is that there are definitely small gaps at the end/start of the tracks in that Amazon download. I loaded two consecutive tracks into an audio editor and the 'gap' is clearly visible and audible as a slight hiccup in the sound. However, when played in WMP and Foobar the transition is smooth. This is because those players anticipate the silence and attempt to cut it out automatically.

From the Wikipedia article it seems likely that the problem is that "The popular MP3 format defines no way to record the amount of delay or padding for later removal.[notes 1] Also, the encoder delay may vary from encoder to encoder, making automatic removal difficult". So whether a there is a hiccup or click probably depends on the combination of which mp3 encoder created the mp3 tracks and then which player is used.

[mathias broucek]

PJPJ,

That was the source of the quote I posted earlier.

mb,

The interesting thing is that there are definitely small gaps at the end/start of the tracks in that Amazon download. I loaded two consecutive tracks into an audio editor and the 'gap' is clearly visible and audible as a slight hiccup in the sound. However, when played in WMP and Foobar the transition is smooth. This is because those players anticipate the silence and attempt to cut it out automatically.

From the Wikipedia article it seems likely that the problem is that "The popular MP3 format defines no way to record the amount of delay or padding for later removal.[notes 1] Also, the encoder delay may vary from encoder to encoder, making automatic removal difficult". So whether a there is a hiccup or click probably depends on the combination of which mp3 encoder created the mp3 tracks and then which player is used.

Thanks - that makes sense.