Power supply filter caps in opposite polarity ?

[Jason G]

Hello
I have a Legend 3OA amp with the problem most of these have which is humm. The last owner replaced the filter caps on the power supply and put them in with one cap - to ground and other + to ground. Which ever end is not hooked to ground is connected to the rectifier diodes. I though the last owner made a mistake and put them in like that but they took the time to draw arows indicating polarity. So I am scratching my head on this one.
Also does anyone know where I can get a schematic?

[teemuk]

Sounds like a dual supply (see http://sound.westhost.com/psu-wiring.htm figure 1). It should be allright.

[Jason G]

After looking at the schem that makes sense.
Thanks for the help!