Tempo doubling on playback

[Sherry C]

Hi Tim,

We haven't had any other reports about such a problem. Is it consistently the same file(s)? Does the behavior repeat itself specifically for the file if you stop, "rewind" to the front, and play it again without doing anything else besides that?

If you've got a particular file that is showing the behavior, you can send it to me at the Helpdesk (support@notation.com) and I'll take a look at it.

Thanks,
Sherry

[Tim Mariott]

Sherry
I have now found that the problem does occur consistently in a specific file on both my laptop running Vista and my desktop running Windows 7 Professional (64 bit).
The attached file is an arrangement of a selection of Rogers and Hammerstein tunes.
1. If you start the playback from measure 228, this should be "It might as well be spring" playing at a constant tempo of 75.
2. But when you get to measure 254, the playback suddenly speeds up, though the tempo display and Graph over Notes does not show any change.
3. However when you reach measure 267 there is a tempo change to 120 for the next song.
I cannot be precise about the speed up at measure 254, but it could well be to a tempo of 120.
So my instinct tells me that perhaps the software has read a whole chunk into memory, noted the tempo change but has applied it pre-emptively some 23 measures before it should be applied. Of course without knowing your software I may be completely wrong but that makes more sense to me than a completely random change of tempo.
I have had other songs where this has happened but I have not made a careful note of the details. If this example is not sufficient I will look out for another.
Thanks
Tim

[Sherry C]

Hi Tim,

Thanks for the file - I am definitely able to hear the problem.

The general case seems to be as you surmised - the tempo changes (both slower and faster) in some cases are applied too far ahead. The caveat that I'm seeing is that it occurs only after some length of measures (which I haven't ferreted out yet). There is a tempo change at measure 32 which does not cause earlier measures to suddenly change tempo, but later on in the file tempo changes are implemented ahead of the graph/event of the tempo change. For example, there is a tempo change at measure 225. If you play back the file starting around measure 210, then that tempo change actually kicks in at measure 214 rather than at measure 225 where it's supposed to. The same problem occurs as you mentioned in your post.

The problem has probably been around for a while, but since very few users create such long files, it has just not shown up. I haven't been able to come up with a good work around for you at present, other than to manually go in, ferret out where the incorrect tempo changes are occurring, and adjust accordingly to fit the music better. It's a totally unacceptable (from a programming point of view) workaround, but at present I have no better one to offer. I'll write this problem up for fixing, but we're in transition right now (looking for a developer since the passing of Mark Walsen) so I can't make any promises about when the problem will get fixed.

Sorry for the bother here. This sounds like a great choral medley to perform - I wish I were singing with you folks!

ttfn,
Sherry

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