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
As far as "how far one needs to take it"...

I'd say the higher quality the better. Nichicon Muse are what I consider my "middle-end" caps.

At some point I'll probably build a Mini PSU using Jensen 4-pole caps ($90+ each) like I use in my amp. But that's a monster power supply that I've only seen in $30k+ amplifiers so if ANYTHING was overkill for a Mini that would be it.

If you are going to build a PSU yourself make sure you have proper tolerance parts. They need to be able to handle the 2-6A that the Mini draws depending on the peripherals attached. That means rectifier diodes and regulators need to be appropriate. There is also an "iSense" connector that needs a resistor attached to it.

If it's a project you're thinking of undertaking I'm happy to recommend some parts as well.
Thank you Mintzar!

If I may bother you further, did you just follow the data sheet schematics for the LM 338? I realize that one can never take a PS too far, I guess what I was curious about was "how far" you need to go to get the noticeable improvement you commented upon.
I know a couple of people that use the Ultra-Fi ECM in their MAC Mini based digital rigs and they feel it is a tremendous upgrade. Here's a link to one that is currently for sale. I'm not affiliated with this seller (don't even know him), but I do know the manufacturer and a couple of his customers who use the ECM. I'm not endorsing the product as I haven't heard it yet. Just passing along some information......

http://www.audiogon.com/cgi-bin/cls.pl?powrcond&1284048765&/Ultra-Fi-ECM-music-server-cond
I use Isolation transformers in my system that I modified to great benefit. I am yet to find a power conditioner that works better than the Isolation transformers. The ECM is a transformer-based conditioner. So I imagine it's decent. I just use hospital grade TXs made by Topaz, which are considerably better than the ECM (though bigger, heavier, and uglier).

I partially followed the datasheet for the LM338. I used a LM337 for the negative rail (which doesn't draw much current, I believe it's only duty is iSense).

I think just going from a switchmode supply to a linear supply would give a great benefit, I just wanted to take it a step further and put some decent parts in the supply.

There's a few regulators based on the LM317 that you can just do a parts swap (with a little research).
Before spending money on power supply or expensive power cord, please try the snap-on ferrite cores first to reduce digital noise. Just snap one on each end of all your power cables and digital cables. They are very effective and cheap.