slightly dumb question about power supplies

[caress]

if i'm using a keyboard that needs a 9-12v CENTER POSITIVE adaptor, does that make it positive ground?

[petemoore]

  Nope...that means they've assigned the pin as the + on the jack.
  Pretty sure the 9-12v keyboards are neg gnd.

[Zben3129]

"The only dumb question is the one not asked"

Sorry, had to say it 

Zach

[caress]

"The only dumb question is the one not asked"

Sorry, had to say it 

Zach

true.  my first thought actually, as i wrote the subject line...   

  Nope...that means they've assigned the pin as the + on the jack.
  Pretty sure the 9-12v keyboards are neg gnd.

ok.  that makes sense to me.  it's a yamaha vss-30, btw.