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View Full Version : New 85Watt MBP Adapter Noisy



sjobs
12th September 2007, 03:50 AM
Hey all,

Got a brand new slim 85watt magsafe adapter and it squeals in a pulse like manner when the adapter is unloaded (no laptop connected). When it's loaded (connected but not charging - just powering) with a laptop it buzzes and when it's charging the laptop it has a low level growl type buzz.

Anyone else notice this? I'm using it in a sound studio where there is virtually no noise in the mixing room and the buzz from it is driving me nuts! It's louder than the laptop. For the more deaf amongst you, I'd suggest putting the PSU near your ear if you could!

So in summary, I'm wondering if the PSU is faulty or it's an 'operational characteristic'? If so, I'll just warranty it. :)

Input? Thanks! :)

gelfie
12th September 2007, 07:16 AM
My (ancient by now) G3 ibook power adapter had a high pitched whine when nothing was connected to it.

But it did not buzz or anything like that when it was connected to the laptop.

I left mine alone, but I'd get yours checked out. Especially as charging etc is usually done when you're sleeping too.

Big Fire. Bad Start To Day.

Squozen
12th September 2007, 07:23 AM
Keep us updated, as I want to get one of these myself. If they're all like that I'll stick with the one that came with the laptop, which is dead silent.

Mikey D
12th September 2007, 07:51 AM
Sounds fucked, mine doesn't make any noise at any time.

edit: It does have a noise when disconnected, but i had to put my ear right up to it in order to hear it. Suffice to say that if you can hear it from more than 5 cm away, there's likely something wrong with it. :)

g5agogo
12th September 2007, 09:55 AM
This sounds very much like high frequency sonics from an inductor (possibly but less likely an electrolytic capacitor spewing it's guts (as I like to call it) too, but you'd know all about that reasonably quickly).

Given that it's probably the inductor, it's unlikely to give you an immediate electrical problem, but you can get some mechanical fatigue after a long time, but it is likely to be bloody annoying and can end up causing electrical noise problems too, (if you have sensitive amps, pick-ups, low signal leads etc nearby).

You should take it back as (doa?) and have it replaced. Tell them you have a noisy inductor and it interferes with your recording work.

LCGuy
12th September 2007, 10:27 AM
Interesting...do the MacBooks use the same 85W power adaptor as the MacBook Pro? I'm hoping that Apple power adaptors have come a long way...i remember when my PB1400 was under warranty its power adpator was replaced about 3 times.

Ruotian
12th September 2007, 01:11 PM
Isn't the new 85 watts the one that replaced the old fatty 85 watts in Macbook pros?

Brains
12th September 2007, 01:37 PM
iMarty: I would consider that MagSafe adaptor as faulty -- power supplies are not meant to make any noise 9especially Apple's). Return it to place of purchase for exchange, as soon as you can.


B.