MBP / Akai MPK49 / Apogee Duet / BUS Power ?

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Level 1

110 points

MBP / Akai MPK49 / Apogee Duet / BUS Power ?

I cannot seem to get my MPK49 to work when I have the DUET hooked up at the same time.
Is this a BUS power issue?

I tried to use the AC Adapter with the MPK49 but I think that turns off the Midi over USB info...

Any ideas?

MBP C2D 15": 2.4GHz / LogicPro 8, Mac OS X (10.5.2), Sharing knowledge is the key to immortality

Posted on Sep 6, 2008 5:07 PM

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Answer 1

Eriksimon

Level 6

15,428 points

Sep 7, 2008 2:28 AM in response to One Ohm

One Ohm wrote:

(snip)

I tried to use the AC Adapter with the MPK49 but I think that turns off the Midi over USB info...

Any ideas?

Do you think it does or are you sure (manual?)?

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Answer 2

One Ohm Author

Level 1

110 points

Sep 7, 2008 9:55 AM in response to Eriksimon

IDK, it is still not being recognized by Audio/Midi Setup even with the adapter.

This is all I found in the Manual:

"Question: Do I need to use a power adapter if I am using the MPK49 with a computer?

Answer: No. The MPK49 will draw power directly from the USB port. However, if your USB port does not supply enough power or if you are using a USB hub, it may be necessary to use the adapter."

Right now I am using the MIDI I/O. But the unit does work without the DUET hooked-up.

Thoughts?

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Answer 3

Eriksimon

Level 6

15,428 points

Sep 7, 2008 10:05 AM in response to One Ohm

Well, it doesn't say anything about disabling MIDI, and it would have been very strange - what use would the adapter be if it rendered your keyboard useless? Anyway, all I can say is that USB power should work, provided it is plugged directly in the Mac, not in a hub and not in the keyboards USB ports (which is a hub too). But with the adapter things should work exactly the same.

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Answer 4

One Ohm Author

Level 1

110 points

Sep 7, 2008 1:55 PM in response to Eriksimon

My point in assuming that the adapter will disable the USB function is because the unit has MIDI I/O.
So, the unit would not be rendered useless...Why use the power adapter and USB when the unit is bus powered?

I think the Duet is tapping ALL of my 'BUS' power...

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Answer 5

Sep 7, 2008 2:26 PM in response to One Ohm

ehhh, the MPK49 use a usb-port, the Duet use a firewire-port, right ?
why should there be a bus power problem ?
firewire has nothing to do with usb.

maybe i misunderstand something ...

cheers

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Answer 6

ambient8

Level 2

295 points

Sep 7, 2008 7:50 PM in response to One Ohm

I had power issues with MPK49 on internal USB bus in rear of Mac Pro and a fully powered Sonnet card as well. Issue only stopped when I plugged it into front USB port. I am assuming that there was not enough bus power in the other ports since they were pretty much all used up, not even by bus powered devices that is. It would power on but there would be not backlighting in the LCD.

Based on what you are saying it is competing for bus power and power adaptor should be the way forward.

Did it ever show up in Audio/MIDI Setup prior to using the power adaptor?

Only limit I know about MIDI on the MPK49 is that the MIDI ports are not active when it is using MIDI over USB. Not heard that power adaptor will stop USB over MIDI from workng.

Cheers

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Answer 7

Pancenter

Level 6

14,788 points

Sep 7, 2008 8:08 PM in response to One Ohm

One Ohm wrote:

I think the Duet is tapping ALL of my 'BUS' power...

From everything I've read on this and other forums... the Duet draws quite a bit of power.

re:
MIDI I/O does draw bus power and evidently the MPK49 is not wired in such a way that the power adapter powers the MIDI section. If you have both plugged in, does the MPK immediately start working as soon as the Duet's firewire is disconnected?

pancenter-

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