I added this enquiry to another post but got no response so I’m starting a new topic in the hope someone can answer my burning question.

I’m in Australia and I have had a power supply problem that defies explanation so I thought I’d ask the question here. First some background: Bought a Metal Muff in Houston and returned to Aust. Worked great, then one night at a gig I plugged in the noname brand 9VDC 1000mA supply I use for all my other pedals (in a daisy chain) and the MM stopped working – I didn’t know why at the time. As I bought the MM in USA no warranty in Aust!! Took it to the warranty agent to have a look; he thought it was the bypass switch so he bypassed the bypass switch ($40) but no good. A friend was in Houston so I asked him to get me another one. Same thing happened again! This time I twigged it must be the power supply. As I said I have used the same power supply for all my other pedals on a daisy chain (Boss, Digitech, Vox, Seymour Duncan etc.) and it is fine. I checked the voltage and polarity and it is perfect. So I sent both MMs with my sad story to EHX in USA and waited. About 2 weeks later the two MMs were returned in perfect working order but no note to say what the problem was or why it happened.

Can anyone shed any light on why this may have happened? The only thing I can think of is that somehow the power supply let some of the 60Hz AC signal through and the MM wasn’t able to handle it but as I said there is no problem (or noise) with the other pedals and my multimeter shows a flat 9VDC output. And while we have 240V AC 60Hz mains here, 9V DC is the same everywhere – right? And I assume that the pedals sold in Aust are identical to the ones sold in the USA. I have been into my local music shop who sells EHX pedals and got a new MM off the shelf and plugged in a Boss power supply and it works fine.

So now I’m in a quandary; do I plug in another 9VDC power supply (I now have a Boss Brand 1000mA PS in a Boss pedal board case) and risk it or play it safe and live with batteries for ever in the MM. Does daisy chaining the PS have any effect? I can’t see how. I suppose I could see if I can buy a EHX brand power supply but the instructions that came with my MM say specifically that the EHX PS is the same as a Boss or Ibanez PS although it says they are 9.6V DC but the battery is only 9V so the specific voltage shouldn’t be a problem.

Cheers

AA