[BUG][DENIED] Simult sequence plays past copy of itself wh

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[BUG][DENIED] Simult sequence plays past copy of itself wh

By Jamon Tue Aug 28, 2012 10:39 pm
XL 3.20

If you record a Sequence 1
Then go to Sequence 2 and set SS 1 : 100
When you press play you hear Sequence 1 while in Sequence 2

If you now go to Sequence 1 to modify it
When you record it plays back how it was
So if it had 1 2 3 4, and you press [REC]+[PLAY START] but record nothing, then you would expect to hear nothing, because those notes are being wiped with the new recording of nothing.
Instead, you hear 1 2 3 4.

If you experiment with just recording and playing, it behaves strangely, seeming to be playing some cached copy that doesn't always update.
One way to force an update is to be in Sequence 1, then set SS 1 to SS OFF, then set it back to SS 1. Then it plays back what you'd expect.
Last edited by Jamon on Sun Sep 02, 2012 5:37 pm, edited 3 times in total.

Re: [BUG] Simult sequence plays past copy of itself when cha

By Jamon Wed Aug 29, 2012 5:51 pm
Try it.

1. Set Sequence 1 to loop, and record a few notes.
2. Press [REC]+[PLAY START] and you hear nothing because the recorded notes are overwritten with no notes.
3. Press [STOP] then [UNDO] to get the notes back, and set SS to 1.
4. Press [REC]+[PLAY START] and you hear the recorded notes play.
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Re: [BUG] Simult sequence plays past copy of itself when cha

By Sooty_G Sat Sep 01, 2012 4:39 am
Jamon wrote:If you experiment with just recording and playing, it behaves strangely, seeming to be playing some cached copy that doesn't always update.


that's because that's exactly how this feature works. it plays back a cached copy of the simulted sequence. the cache is created when you switch the simult seq on. i'm sure this is the ONLY way it can work because when you think about all the work the MPC has to do to play back everything in a sequence, playing back 2 on top of each other must be a real cpu strain. no way to calculate all that stuff in realtime so you get a 'frozen' copy of the sequence. i've never had a problem using it that way.

i personally would rather have that then no simult seq at all (it's already been removed in the 128XL os). i use simult seq all the time and it being missing in the new OS is a major sore spot with me.

Re: [BUG] Simult sequence plays past copy of itself when cha

By Jamon Sat Sep 01, 2012 4:48 am
That's fine, but it shouldn't play the cached copy as you record over it should it? It should be that if SS X == Sequence X, then it turns off SS internally until you switch to another sequence. If you're in the sequence set as simult sequence, then it should behave normally; but if you're out of it, it should play the cached copy.
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Re: [BUG] Simult sequence plays past copy of itself when cha

By Sooty_G Sat Sep 01, 2012 8:26 pm
Jamon wrote:That's fine, but it shouldn't play the cached copy as you record over it should it? It should be that if SS X == Sequence X, then it turns off SS internally until you switch to another sequence. If you're in the sequence set as simult sequence, then it should behave normally; but if you're out of it, it should play the cached copy.


it's not going to work because again, the cpu will have to do double the work to play back a 'live' simult seq - especially if you are recording & entering notes & qlinks etc in realtime. the mpc will have to be listening & recording what you do live, then recalculating all of it again to play back immediately. would overload the cpu plus introduce all sorts of lag in the simulted seq.

the mpc has lots of features that only work or can be modified when the sequencer is stopped. the reason for that is the cpu limitation. no way around it. the simult seq must be cached to work.


plus... i'm having trouble understanding why you would want or need to simult the same seq on top of itself while you are recording it?

Re: [BUG] Simult sequence plays past copy of itself when cha

By Jamon Sat Sep 01, 2012 8:33 pm
That's the point, that's what it's doing now, it is playing the simult sequence on top of itself while recording. That must be a mistake.

If your SS is 1, and you're in Sequence 1, the Simult Sequence stuff should internally be disabled, right? It makes no sense to simult itself.

But it doesn't do that. If your SS is 1, and you're in Sequence 1, when you are recording as normal it is not acting as if SS is OFF, it is playing the simult sequence in the same sequence.

Do you see what I'm saying? If SS is X, and you're in Sequence X, internally it should just shut off Simult Sequence mode. But it does not do that, so when you record, and it is changing the sequence as you record, it is playing back the cached copy of the same sequence you are in.
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Re: [BUG] Simult sequence plays past copy of itself when cha

By Sooty_G Sat Sep 01, 2012 8:48 pm
Jamon wrote:That's the point, that's what it's doing now, it is playing the simult sequence on top of itself while recording. That must be a mistake.


no way! that's the best part of simult seq. i simult a sequence on top of itself all the time to get interesting phasing effects.

i just never have it simulted with itself while recording as it doesn't make sense to do so obviously, so just turn it off before you start recording.

but you wouldn't want JJ to disable it globally during recording. what if you were recording in seq 1 & had it simulted with seq 2? you would want the simulted seq 2 to keep playing during recording so you could listen to it to judge your timing.

Re: [BUG] Simult sequence plays past copy of itself when cha

By Jamon Sat Sep 01, 2012 8:57 pm
In programming you can check for stuff like that:

Code: Select allfunction armRecord() {
    if (currentSequence == simultSequence)
        disableSimultSequence();
    record();
    enableSimultSequence();
}


Playing a sequence with itself for phasing effects is quirky. Just because you like the side-effects of a bug doesn't mean it's not a bug.
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Re: [BUG] Simult sequence plays past copy of itself when cha

By Sooty_G Sun Sep 02, 2012 12:34 am
Jamon wrote:Playing a sequence with itself for phasing effects is quirky. Just because you like the side-effects of a bug doesn't mean it's not a bug.


oh! heaven forbid anyone do anything quirky!! can't have any thinking outside the box, now can we?

a good programmer allows these sorts of decisions to remain in the hands of the user, so they can take the hardware/software in their own direction and not necessarily the one you've personally approved for them. i'm glad you're not programming the jj os.

Re: [BUG][ACCEPTED] Simult sequence plays past copy of itsel

By Jamon Sun Sep 02, 2012 5:37 pm
JJ OS wrote:When the same sequence as a main sequence is set to SS, what is played doubly is specification.
From OS1, since it is the same specification, this specification cannot be changed.
If it changes, a claim will arise from other users.
When you set and record the same sequence as a main sequence to SS, please turn OFF SS and record it.
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