I forgot my power supply in Denver over spring break. I purchased a 12v and a 9v at goodwill. The internet says that the 404sx uses a 9v, but I'm almost positive that i was using a 12v roland adapter before. Is it a bad idea to use a 3rd party power supply?

The 404 and a lot of other Roland stuff uses the psb1u. It's a 9v 1amp power supply. I've used a 9v 300ma before and it worked fine. Just make sure you get a power supply with the same polarity http://en.wikipedia.org/wiki/Polarity_symbols

Do not use a 12v power supply.

I would advise getting a power supply with the same specs as the original. 3rd party is fine.

be careful not to get one with too much ampherage. You can overheat/melt stuff.

The official (at least for SX) power supply is 9V, 2A. 18W max.

You don't need that much amps as Formal said, but definitely don't go over if you can help it.

hey, thanks guys.