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        MIDI-OX >> Wish List >> Incoming Midi Clock Jitter Display
        
(Message started by: Innerclock on Oct 24^th, 2005, 8:50pm)

Title: Incoming Midi Clock Jitter Display
Post by Innerclock on Oct 24^th, 2005, 8:50pm

When reading incoming Midi Clock, could a window be added that reports Midi Clock stability/jitter? Midi-OX could take a mean/average of clocks received over a certain time period and then display varience. This would be very useful when testing reliability of various serial, usb, pci and Firewire midi interfaces and their drivers when accurate slaving to external Midi Clock is required.

Title: Re: Incoming Midi Clock Jitter Display
Post by Jamie OConnell on Oct 24^th, 2005, 10:03pm

Interesting idea... I can guarantee that there is significant jitter associated with all of them, although it is possible to sync to an average.

Title: Re: Incoming Midi Clock Jitter Display
Post by Innerclock on Oct 24^th, 2005, 11:48pm

I run a variety of midi software applications but slave all of them off a very accurate midi clock master device. As Midi Clock Slave applications they all are at the mercy of the Midi Interface that drives them and how solid the driver design is as far as clock jitter is concerned. At present, there is no application I can find that reports introduced midi clock jitter. Do you think it might be possible to add this as a Midi-OX feature?

Title: Re: Incoming Midi Clock Jitter Display
Post by Jamie OConnell on Oct 25^th, 2005, 3:22pm

Maybe. It would also be possible to do this by logging a few seconds of the timestamps that the F8 clocks come in on, copying them into a spreadsheet, and then calculating statistics based on their variance. There are 24 F8's arriving per beat. Timestamps and arrival time (MIDI timing) under Windows is limited to millisecond accuracy.