Policy regarding silent HTOA

What is the policy on short, acoustically silent data in the pre‐gap of track 1?

Should it be included as a [silence] pre‐gap track in the tracklist like here?

I have a couple of releases where the HTOA is acoustically silent (usually between 1 and 3 seconds) but not digitally.

There is an older thread about this topic but it didn’t come to any conclusion.

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Silence that is pre-gap should not be counted.
An audio CD is more like a record than a digital storage medium.
Tracks on an audio cd are pcm audio data with 2 seconds of silence between tracks.
There is a table of contents that has sector offsets of tracks to indicate how tracks are laid out on the tracks.

Pre-gap tracks are a trick that have been put in the space before the first track and are not widely supported. On some early cd players you could start at the first track and press rewind and go before the start of the cd to reveal the hidden track.
There are a few cd’s that have proper audio in this sector.
I have The Calling where there is some spoken word, we do want this information in the database.

Silent pre-gap tracks we don’t need and is put there by manufacturing, when they put tracks on the cd and where they put the first track on the cd. Cd’s produced by one batch can be different from another batch. In your example you have one cd with the first track starting at sector offset of 150 and 182 with the other.


Thanks for the answer! I see that in the meantime, the track in question was removed from the release (https://musicbrainz.org/edit/75263352).

For those interested, there has been a similar discussion on GitHub what to do with those tracks. One particular comment stood out to me:

The Internet Archive (archive.org) has the following policy for their Audiophile CD collection:

If the HTOA is less than 75 frames (1 second), or has a peak less than 1e-10, then discard it.

If that is true, that would mean a slight divergence from MusicBrainz’ policy, then.

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What difference?
We say if difference we don’t show it, is like their second part.

Well, I’m making the assumption here that the Internet Archive will NOT discard a HTOA if both of the stated conditions are not met. In other words, I’m assuming that if frames(HTOA) >= 75 and peak(HTOA) >= 1e-10, the track will not be discarded.

Take e.g. this disc ID:
The first track starts at sector 300. According to my logs the peak level of the HTOA is 3.1e-05.
It is still acoustically silent.

According to @dns_server, it should be discarded:

Silence that is pre-gap should not be counted.

According to the Internet Archive, it would be kept.

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