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USB for power/config - MIDI for data?

PostPosted: Tue Apr 21, 2009 10:21 am
by gabriel1712
I use a dedicated ASIO soundcard and the manual states DIN MIDI is way faster than most USB MIDI:
Practical tip: Even if your input keyboard (master keyboard) has a USB connection available, you should use the MIDI input (IN) of the PHASE 22 system whenever possible: the “direct connection” to the PCI data bus of the computer, and thus to the MIDI software, allows a substantially faster and more stable timing than most USB-MIDI interfaces. Of course, the same is true for the output when it is needed.

Is that true for MD as well? I may have rely on MinScan to get my mesh snare/toms right, so low initial latency is crucial.

If I should use DIN MIDI, how is config data (MCT: send to/from MD, MIDI-OX update firmware... etc) send? Can USB be used for that and power or do I have to use an external power source and DIN MIDI IN on the MD?

Re: USB for power/config - MIDI for data?

PostPosted: Tue Apr 21, 2009 10:50 am
by dmitri
gabriel1712 wrote:I use a dedicated ASIO soundcard and the manual states DIN MIDI is way faster than most USB MIDI:
Practical tip: Even if your input keyboard (master keyboard) has a USB connection available, you should use the MIDI input (IN) of the PHASE 22 system whenever possible: the “direct connection” to the PCI data bus of the computer, and thus to the MIDI software, allows a substantially faster and more stable timing than most USB-MIDI interfaces. Of course, the same is true for the output when it is needed.

Is that true for MD as well? I may have rely on MinScan to get my mesh snare/toms right, so low initial latency is crucial.

If I should use DIN MIDI, how is config data (MCT: send to/from MD, MIDI-OX update firmware... etc) send? Can USB be used for that and power or do I have to use an external power source and DIN MIDI IN on the MD?

USB MIDI implementation in PIC18F2550 firmware doesn't add noticeable latency - less than 1ms. How much latency exactly PC adds once MIDI data are in via USB I don't know. You can look at http://megadrum.ucoz.ru/index/0-6 and it states that the combined latency between the moment the pad is hit and the PC producing sound is 5-6ms so I don't think MIDI over USB adds anything (ASIO for M-audio Audiophile 2496 was configured to use 128Byte buffer).
But of course you can use USB just for power and do everything else over standard MIDI ports, including firmware update and MegaDrum control using MCT.

Re: USB for power/config - MIDI for data?

PostPosted: Tue Apr 21, 2009 11:42 am
by gabriel1712
Great, thank you, Dmitri.

Re: USB for power/config - MIDI for data?

PostPosted: Tue Apr 21, 2009 11:49 am
by gabriel1712
dmitri wrote:You can look at http://megadrum.ucoz.ru/index/0-6 and it states that the combined latency between the moment the pad is hit and the PC producing sound is 5-6ms...

Great article! I especially like the part where the dwarfen queen smacks the groupie with a dead trout wrapped in a popular russian science magazine ;)