A technical support community for Apple Logic Pro users.

 
teerathm
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Posts: 6
Joined: Tue Jun 30, 2020 6:33 pm

Arpeggiator Skipping Beats

Tue Jun 30, 2020 6:43 pm

Hi all

I ran into an issue with the Arpeggiator today where it's skipping beats regularly instead of being continuous. This happens when the song is playing but not when it is stopped and I play something on my MIDI keyboard. I couldn't figure out what's going on. Anyone faced this issue before and have a solution?

Here's a link to the screen capture: https://drive.google.com/file/d/1aY5YwN ... sp=sharing

Thank you
Logic Pro X 10.5.1
MacBook Pro 15" (2019) , Core i9 (2.3 GHz), 32 GB, OSX 10.14.6
 
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Atlas007
Posts: 8770
Joined: Mon Dec 14, 2009 11:58 pm
Location: Montreal

Re: Arpeggiator Skipping Beats

Tue Jun 30, 2020 8:17 pm

Have you tried slowing down the Arp rate? Perhaps that the synth plugin isn't able to respond fast enough.
Or, if possible, increase its voices count (make it polyphonic)...
LogicX 10.5.1 ( & 9.1.8),MainStage3.4.4
MBPro 17", Core2Duo, 8G, OSX 10.12.6
MacPro, Xeon 6Cores, 64GB, OSX 10.15.5
ULN8, MOTU MIDI TP-AV, C4, Eucon McControl, KorgNano, Novation SLMkII
AAS, NI, Celemony, Spectrasonics, Korg, MIDIQuest, etc...
PC, iPad3(V-Control & LogicRemote), AtariST(Notator SL), Several vintage gear
 
teerathm
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Posts: 6
Joined: Tue Jun 30, 2020 6:33 pm

Re: Arpeggiator Skipping Beats

Tue Jun 30, 2020 9:00 pm

I tried both, but still the same result. Reducing the rate to 1/16 creates 1/8 notes, and reducing to 1/8 note results in only one 1/8 note in the beginning and then no sound. The same happens when the synth is polyphonic.
Logic Pro X 10.5.1
MacBook Pro 15" (2019) , Core i9 (2.3 GHz), 32 GB, OSX 10.14.6
 
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Atlas007
Posts: 8770
Joined: Mon Dec 14, 2009 11:58 pm
Location: Montreal

Re: Arpeggiator Skipping Beats

Tue Jun 30, 2020 9:15 pm

Some synth plugins, besides being set to polyphonic mode, also require to increase their number of voices.
Last edited by Atlas007 on Tue Jun 30, 2020 9:19 pm, edited 2 times in total.
LogicX 10.5.1 ( & 9.1.8),MainStage3.4.4
MBPro 17", Core2Duo, 8G, OSX 10.12.6
MacPro, Xeon 6Cores, 64GB, OSX 10.15.5
ULN8, MOTU MIDI TP-AV, C4, Eucon McControl, KorgNano, Novation SLMkII
AAS, NI, Celemony, Spectrasonics, Korg, MIDIQuest, etc...
PC, iPad3(V-Control & LogicRemote), AtariST(Notator SL), Several vintage gear
 
teerathm
Topic Author
Posts: 6
Joined: Tue Jun 30, 2020 6:33 pm

Re: Arpeggiator Skipping Beats

Tue Jun 30, 2020 9:17 pm

Atlas007 wrote:
Some plugins, besides being set to polyphonic mode, also require to increase the number of voices.

I did increase the voice number to 16.
Logic Pro X 10.5.1
MacBook Pro 15" (2019) , Core i9 (2.3 GHz), 32 GB, OSX 10.14.6
 
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Atlas007
Posts: 8770
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Location: Montreal

Re: Arpeggiator Skipping Beats

Tue Jun 30, 2020 9:19 pm

The attack time should also be set to minimum; but I think that your synth sound's attack is already set to very short.
To troubleshoot the source of the issue, have you tried with another plugin?
Another thing I would try would be to quit and restart Logic; and then cold reboot your computer, if restarting Logic didn't help.
LogicX 10.5.1 ( & 9.1.8),MainStage3.4.4
MBPro 17", Core2Duo, 8G, OSX 10.12.6
MacPro, Xeon 6Cores, 64GB, OSX 10.15.5
ULN8, MOTU MIDI TP-AV, C4, Eucon McControl, KorgNano, Novation SLMkII
AAS, NI, Celemony, Spectrasonics, Korg, MIDIQuest, etc...
PC, iPad3(V-Control & LogicRemote), AtariST(Notator SL), Several vintage gear
 
teerathm
Topic Author
Posts: 6
Joined: Tue Jun 30, 2020 6:33 pm

Re: Arpeggiator Skipping Beats

Tue Jun 30, 2020 9:22 pm

I tried all of these methods. I don't think the issue is with the synth. I tried it with other synths and the result is the same. Plus, it works perfectly when the song is not playing and I play something on my MIDI keyboard. Why is it working then and not when the song is playing?
Logic Pro X 10.5.1
MacBook Pro 15" (2019) , Core i9 (2.3 GHz), 32 GB, OSX 10.14.6
 
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Atlas007
Posts: 8770
Joined: Mon Dec 14, 2009 11:58 pm
Location: Montreal

Re: Arpeggiator Skipping Beats

Tue Jun 30, 2020 9:40 pm

It works fine here.
Have you tried resetting your Core Audio or rebooting Logic and/or your computer?
If the above didn't help
Perhaps uploading your project so someone could inspect it...
BTW, which (precise) version of Logic are you running?
LogicX 10.5.1 ( & 9.1.8),MainStage3.4.4
MBPro 17", Core2Duo, 8G, OSX 10.12.6
MacPro, Xeon 6Cores, 64GB, OSX 10.15.5
ULN8, MOTU MIDI TP-AV, C4, Eucon McControl, KorgNano, Novation SLMkII
AAS, NI, Celemony, Spectrasonics, Korg, MIDIQuest, etc...
PC, iPad3(V-Control & LogicRemote), AtariST(Notator SL), Several vintage gear
 
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rAC
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Re: Arpeggiator Skipping Beats

Wed Jul 01, 2020 3:08 am

Just maybe, telling us what is your computer and what version of logic you are using would be helpful. Have a look at what is asked for in your signature block on your profile and fill that in. It gives us more to work with regarding your problem and may help getting to a solution.
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teerathm
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Posts: 6
Joined: Tue Jun 30, 2020 6:33 pm

Re: Arpeggiator Skipping Beats

Fri Jul 03, 2020 6:33 pm

Sorry for the delayed response. It seems like the problem occurs when the sample rate is 48 kHz and buffer size is >= 256 samples. I lowered my buffer size to 128 and it worked. Can others confirm if this is the case for you?
Logic Pro X 10.5.1
MacBook Pro 15" (2019) , Core i9 (2.3 GHz), 32 GB, OSX 10.14.6
 
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Atlas007
Posts: 8770
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Location: Montreal

Re: Arpeggiator Skipping Beats

Fri Jul 03, 2020 10:27 pm

teerathm wrote:
Sorry for the delayed response. It seems like the problem occurs when the sample rate is 48 kHz and buffer size is >= 256 samples. I lowered my buffer size to 128 and it worked. Can others confirm if this is the case for you?

Thanx for sharing your experience and solution!
LogicX 10.5.1 ( & 9.1.8),MainStage3.4.4
MBPro 17", Core2Duo, 8G, OSX 10.12.6
MacPro, Xeon 6Cores, 64GB, OSX 10.15.5
ULN8, MOTU MIDI TP-AV, C4, Eucon McControl, KorgNano, Novation SLMkII
AAS, NI, Celemony, Spectrasonics, Korg, MIDIQuest, etc...
PC, iPad3(V-Control & LogicRemote), AtariST(Notator SL), Several vintage gear
 
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Mark R
Posts: 386
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Location: Tumwater, WA

Re: Arpeggiator Skipping Beats

Sat Jul 04, 2020 9:04 am

teerathm wrote:
It seems like the problem occurs when the sample rate is 48 kHz and buffer size is >= 256 samples. I lowered my buffer size to 128 and it worked. Can others confirm if this is the case for you?


Thanks @teerathm.
Bug confirmed here on both my laptop and iMac systems!

Noticed your time signature was 7/8. I set mine to 4/4 and still had the issue.
Also noticed that manually changing and returning the tempo to 75bpm during playback temporarily corrects the issue.

Steps to reproduce:
    Set Tempo to 75bpm
    Set Sample Rate to 48KHz (or 96KHz)
    Set Buffer Size to 256 or above
    Set Arpeggiator rate to 1/32 or faster
    Playback a MIDI region of one or more held notes

Instead of outputting a steady series of notes the Arpeggiator will be skipping steps.

this should not be happening... we should report as bug!
Last edited by Mark R on Sat Jul 04, 2020 9:39 am, edited 1 time in total.
Logic 10.5.1 | Mojave | retina iMac 4GHz i7 32GB
Logic 10.4.8 | High Sierra | MacMini 2.3GHz, i7 16GB
 
teerathm
Topic Author
Posts: 6
Joined: Tue Jun 30, 2020 6:33 pm

Re: Arpeggiator Skipping Beats

Sat Jul 04, 2020 9:34 am

Mark R wrote:
teerathm wrote:
It seems like the problem occurs when the sample rate is 48 kHz and buffer size is >= 256 samples. I lowered my buffer size to 128 and it worked. Can others confirm if this is the case for you?


Thanks @teerathm.
Bug confirmed here on both my laptop and iMac systems!

Noticed your time signature was 7/8. I set mine to 4/4 and still had the issue.
Also noticed that manually changing and returning the tempo to 75bpm during playback temporarily corrects the issue.

Steps to reproduce:
    Set Tempo to 75bpm
    Set Sample Rate to 48KHz (or 96KHz)
    Set Buffer Size to 256 and above
    Set Arpeggiator rate to 1/32 or faster
    Playback a MIDI region of one or more held notes

Instead of outputting a steady series of notes the Arpeggiator will be skipping steps.

this should not be happening... we should report as bug!


Thanks, Mark R! We should definitely report this.
Logic Pro X 10.5.1
MacBook Pro 15" (2019) , Core i9 (2.3 GHz), 32 GB, OSX 10.14.6