12v into 9v - what will happen?

[Pigmy Pony]

Hi all,

I have an SMSL dac which I'm wanting to put in the AOS swap shop, but I seem to have lost the adaptor plug for it. All I can find is one that outputs 12v, while the dac wants 9v. Can this be used, or will it bugger up the SMSL?

[dave2010]

Hi all,

I have an SMSL dac which I'm wanting to put in the AOS swap shop, but I seem to have lost the adaptor plug for it. All I can find is one that outputs 12v, while the dac wants 9v. Can this be used, or will it bugger up the SMSL?Not a good idea, I think.

You could offer it without the psu.

[struth]

Much depends on the voltage reg in the unit but without being sure from data sheet I wouldn't do it

[Firebottle]

Yes it all depends on whether there are internal regulators, and if so what the maximum they can cope with is.

[Light Dependant Resistor]

Also that it is assumed 9v DC is being discussed, when it could be 9v AC , 9V AC once full wave rectified being 12.7v DC

and if 9VDC that some naughty plugpack manufacturers swap the polarity at the end connector. The most common type is
the middle connector being positive, which is to say some are and might be the other way.

If its AC initially, most common regulators will handle the once rectified 4.2v DC difference. For instance a LM317
rated to 40v input to output differential, a 78xx ( horrible regulators) rated to 35v DC, but exceptions are low dropout LDO types where
typically 20v DC is the maximum - some 24V Dc though. The effect of more initial voltage, adds heat to be dissipated, which may
or may not be allowed for in the design.

Hence as most are saying, supply with the exact adapter.

[Pigmy Pony]

Thanks everyone, I suspected it wouldn't be a good idea, but didn't know why. I'll put it in AOS swapshop sans adaptor and see if anyone wants it.