I used to think that CDs couldn’t run longer than 80 minutes, but I’ve come across some examples of slightly longer durations, so I guess it’s possible.
However, I’ve seen one that runs to 82:30. That seems to me extremely long. Does such an extreme duration have on impact on sound quality ? Is there an increased risk of tracks skipping, especially the last one (CDs are written from the inside out) ? Or is it probably perfectly fine ?
For the record, it’s a commercially available CD, not a CD-R.
I used to work for a CD manufacturer as an Editor. I would prepare customer’s content to make ready for mastering and duplication.
No, a long program length did nothing to affect the sound quality, but because of the finer track pitch and (I believe) slightly slower CLV track velocity needed to fit longer programs, the disc would be prone to playback problems on some players - usually older players.
(Sorry, this was a VERY long time ago, and I know track pitch had to be reduced, but I’m a bit fuzzy on the track velocity.)
We used to specify that a customer must sign a waiver if they wanted to duplicate a program longer than 79 minutes.
car CD mechanisms had problems with non-Red Book-standard 80+ minute CDs up until about 2002-2003. They couldn’t cope with the finer track pitch and would attempt several times to lock on and eventually give up.
One further point to address OP’s question:
As I said upthread, a long program length does not affect the sound quality. It can affect playback on older players and the problem will usually be manifested at the end of the disc/the outside edge.
The physical properties of any disc at the outside edge can be a bit “iffy” and cause the player to not be able to read out there. Birefringence, radial and tangential deviation and substrate thickness can cause playback difficulties.
The physical factors of the disc at the outside edge combined with finer track pitch and slower scanning velocity push the capabilities of the “read” laser, tracking systems and error correction within the player to extremes, and cause the player to just give up.