universal adapter polarity help - don't want to burn the effect pedal

[sitter07]

so i have this is Boss dd7 effect pedal, which needs 9V 1A . I have some universal adapter with extensions but not sure which is the right way to turn it in.

first pic is the back of the pedal. which of these two examples (E1, E2) is correct ?

 

[ChrisP58]

Your first picture shows that the center pin should be negative, and the outer shell should be positive.

Rather than depending on the somewhat cryptic markings, I would recommend using a voltmeter to see which of the two positions produce the correct polarity.

 

[upand_at_them]

As ChrisP58 said, E2 is likely correct but if you don't want to risk damage you should check it. If you're in the US you can get a cheap (often free) multimeter from Harbor Freight.

 

[Visitor]

As ChrisP58 said, E2 is likely correct but if you don't want to risk damage you should check it. If you're in the US you can get a cheap (often free) multimeter from Harbor Freight.

Not any longer. They've dumped the really cheap meters and now still stuff in the $20+ range.

 

[upand_at_them]

Not any longer. They've dumped the really cheap meters and now still stuff in the $20+ range.

Well, not free, but close ($6.49):

Harbor Freight - 7 Function Digital Multimeter

 

[Visitor]

Hmmm. It's interesting if I search for "volt meter" on their website, that meter doesn't show up. It only shows up only if I search "multimeter" does that one pop up.

They've eliminated the really cheap ones, and I suspect that one may be next. I don't think my store had that one last time I looked.

 

[upand_at_them]

I haven't looked at their meters before, but I know that the one I posted above is the one that regularly goes on sale for around $3 and occasionally has a coupon for free. I've given a few away when the free coupons were more often. OP needs to get one.

 

[unclejed613]

if i'm reading the polarity plug correctly E1 is correct with the icon lined up with the sleeve lined up with the + on the other part of the polarity plug.

 

[Visitor]

The + and – symbols on the part showing the connector make it somewhat ambiguous. The safest thing to do is verify the polarity with a meter.