The trick does work on the Roland A49. Any USB power source will turn it on. I have my A49 sitting right next to me and as always just now I was able to turn it on from a USB battery pack. One of the reasons I bought the A49 was because I "thought" from looking at the midi din out I could use it without a computer except that how do you power it with a PC??? That was when I found the trick on the net. It is not even mentioned in the manual. Just recently I purchased a USB MIDI host along with some other midi gadgets including a midi breath controller. The USB MIDI host, of course, will power the A49 no problem. Then I tried Samsung USB chargers and two different USB battery packs to turn on the A49 and send midi out. I don't like when manufacturers have features in their products that either they themselves don't know about or fail to mention in the manual.



When I got a Roland A-49 a few years back, I, too, thought it was stupid the A-49 could not power up as a standalone. I found a trick on the internet.

How do I power up my Roland A49 MIDI controller with a USB power supply (without a computer)?
Article #1725357 Added on Jun 8, 2015 at 2:16 PM
Hold the Function, Assign, and Pitch buttons while plugging the unit in to the power supply to enable the controller to receive power in standalone. Once you�ve done this, each subsequent boot should work normally with the power adapter without having to press that combination of buttons. [/quote]

That works? Funny... A normal USB power adapter apparantly doesn't work.
It's bizarre as I read the A-49 needs some kind of driver to work, either from PC or at least via iPad, but then that's obviously wrong...[/quote]