AC/AC transformer question.

[Buzz]

I have been lucky enough to be at the receiving end of a box full of free rackmount effects.

Amongst the haul is an Alesis Nanoverb and an Alesis Midiverb 4.

Both require an adaptor with 9v AC output. It's written 9VAC~

Question 1: I have an adaptor with 12v AC output. Would that cook it?

Question 2: Does it matter which way the plug is wired?

There is no indication on the items ( or the adaptor ) of which way they are wired. I assume one wire is active and the other neutral much like house wiring. Given this assumption, it would work either way. But you wouldn't want to wire up a house under that assumption.

[GibsonGM]

Hi Buzz...I wouldn't use the 12V, the voltage will be too high. You MAY get away with it, depending on what the component ratings are internally, but I'd stay with what they're calling for to assure that you don't get blue smoke.

As for the "polarity" of the AC transformer...I don't believe there is any 'orientation' there, if you get my drift.  Your assumption is correct.  The circuit's internal ground reference is set in the power supply itself, so in that respect it differs from house wiring, which has its ground point at the service panel.    Really good thought on that, though! 

[Buzz]

Cheers Mike.

[hymenoptera]

9v AC wall warts are probably the most common AC/AC wallwarts out there. There's always a pile for sale on ebay. I try to keep several extras around for when I can't find one.

If you want extra heavy duty check out the big 1A monsters that come with Lexicon rackmount reverbs. They must weigh > 1lb each... You could safely power just about any rackmount 9vAC machine with those things.

[duck_arse]

hey buzz, dig inside under the covers. it's as likely they'll have a regulator following the rectifier, and if they have/do, then the AC input voltage won't matter that much. carefully, though.

you really, REALLY don't want either active or neutral appearing on the low-voltage side of your transformer, plug pak, wart, etc. isolation.

worst comes to worst, I'll swap you a 9VAC for a chisel sharpened.

[Buzz]

hey buzz, dig inside under the covers. it's as likely they'll have a regulator following the rectifier, and if they have/do, then the AC input voltage won't matter that much. carefully, though.

Yeah, that's in the ballpark of my assumptions.

I worked out a path of less resistance. I put a shout out on facebook to see if anyone has one they could part with. Seems like many people end up with a box of orphaned wall warts, much as I have.

Unfortunately reading the numbers on the back referring to the output is like reading hieroglyphics for my mates.

It's kind of refreshing actually. I'm an electronics dumbass in this community, but out in the general population I feel like a genius. I'll pop around and see what they've got.

Cruising around the web looking for an answer I came across this page.

http://www.instructables.com/id/9VAC-power-supply-for-x0xb0x/?ALLSTEPS 

I won't be attempting this. The likelihood of death and / or burning down my house makes those $30 wall warts on Ebay look really cheap.