Mac Mini Power Supply


I recently built a linear power supply for my Mac Mini. The difference in sound quality was one of the single largest performance upgrades I've made to my system in years.

I was wondering if anyone else has had any experience with their mac mini PSU upgrades and what your experiences are. It's one of those upgrades I wish I had made months ago.

I've always been a big believer in the source being the most important component in the system. Followed by the power supply being one of the most important parts within the component. At least in this case, it appears that was correct.
mintzar
It's cheaper than buying the cable from MP3car most times.

And I build my cables into a Powercon for my power supplies so I'd have to chop things up a bit anyway. Unfortunately it bricks the brick to do this so it's a bit of a waste, but there aren't many cost effective alternatives for older Mac Minis.
I wasn't able to find a cheap power brick for my Mini, so I bought the MP3car cable. It works fine.

There is more than one wiring diagram around for the connector. The right configuration has the iSense cable running to ground through a 3.3K resistor. A quarter-watt one is fine.

There are a good many aftermarket power supplies around, or were. I chose a 2009 Mini as being the most recent model that still had an external PS. Easier to work on, adequate for the purpose, and probably easier to resell/reuse too.

I did all the software tweaks, maxed the RAM, put in an SSD and found a linear PS for the (external, FireWire 800) music drive. That PS was a 12V Acopian Gold Box model from eBay.

Finding a power supply for the Mini was hard. I didn't want to pay a lot because I had no proof it would really make a difference, aside from the small improvement in clarity and coherence I got when I upgraded the hard drive's PS.

Eventually I found an 18V Acopian Gold Box A with +/- 0.5V adjustable output voltage, at a price I was willing to pay. It was an older unit but Acopian worked very kindly with me to get it running. It needed new filter caps. These were not hard to find.

My total cost was under $150 and the improvement was, IMO, worth while. Timbres are sweeter, highs are cleaner and the music seems more coherent.
@Tobias, thanks for sharing your experience. Seems you found a diamond in the rough with the Acopian; glad you're happy. Would you mind sharing the model number? I also own a 2009 Mac Mini and the thought of a better PS seems interesting.

--Tom in Saxramento
@ 4hannons, sorry for slow response. The Acopian model I happened across on eBay was A18H1400. That's a Gold Box Type A linear regulated supply rated at 14 amps output.

14 amps of current is somewhat more than the stock Mini power supply's output, which is nominally 10 amps. Message board posts seem to indicate 8.5 amps is quite sufficient. However it's best to keep in mind that some extra power is needed to feed the USB and Firewire buses, so if you power a drive or a DAC from the Mini, you will definitely need headroom.

Acopian model number A15H1150 is definitely big enough. This one is specified as a 15-volt supply; the idea is to require your unit be built to output 18 volts, when you place your order.

Acopian has been really great to deal with, in my experience.
The OP was devoid of any sort of analysis of power supply being stressed such as drooping voltage or current under load, etc. Which supports the idea that it was merely a fishing expedition to sell unneeded power supplies for the Mac Mini. You can easily tell when a mini goes from 'working hard' to 'approaching maximum' by the sound of the cooling fan as it slows down slightly. That is the clue to start monitoring voltages and currents supplied by the PS. My Mac PSs never get more than warm and I doubt they would ever prove inadequate. Any limitations would derive from the mini itself and would depend on its instantaneous loading and its ability to shed chores in response.
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