The MBP battery isn't anywhere near as capable of meeting instantaneous current demands as a good LPS. Thus despite the fact that running off the battery isolates it from noise on your AC mains, you are still left with a noisy computer that's actually doing more harm to the music than the harm caused by your AC.
An excellent low impedance supply can have a profound impact on sound quality from a Mac. Read the many forum posts about Uptone's MMK/JS-2 solution. I had converted a Mac mini and one time and I was stunned at the magnitude of the difference. This is just the starting point though as far as having a decent music server. It gets a lot better once one makes the move to a purpose-built music server.
What instantaneous current demands ? We are not Talking about analog output here.. Pure digital , no peak demands, the Li battery is proven more than capable to meet the demands of heavy graphics and cpu, which I am hardly utilizing.
The Mac mini would benefit by an Lps, but not by much.. The oem PS is actually a very high freq switcher.. not much neg effects, especially considering all the other high frequency clocks and regulators buzzing along inside the computer.
The folks at Manley are using SMPS in their high end recording equipment, they swear by the LOWER noise than LPS. Bruno Putzey designed it for audio and it measures better in every way.. So technology marches ahead..
I still prefer LPS in audio, but am using a smPS
But you haven‘t heard it for yourself, right?
You have a very nice system, by the way. I bet the Athenas sound amazing driven by the XA25.
Good morning Kenny,
I have a Pass ACA amp I built that came with a Meanwell SMPS. The first thing I did was get out an old LPS I built for a headphone amp I had used some years ago. it has a 24v secondary winding in addition to the 12v tap I was using. I wired it up and listened, it was big and bulky and without a proper housing.. but I rigged it to work with the amp.. It wasn’t pretty, but I made it work.. after it fell off the table When I snagged some wires, I put the SMPS in its place for the time being so I could finish up the LPS.. I listened for days, then weeks, still months later, the SMPS is still in place. I sent Nelson Pass a note exclaiming my surprise about the SMPS sounding as good.. He replied that the SMPS by meanwell he researched and chosen had a better peak to peak output with nearly unmeasurable noise than most PS. This SE class A amp is very revealing with only 2 stages, and it sounds Really good, I can’t tell a difference sonically and it’s cool running, a slim covered SMPS lays on the floor out of sight..
So as you stated, I don’t have any experience with the Mac mini, but a similar experience with another component. I think we tend to miss out on improvements on other technologies as time moves along and we keep our non updated prejudices alive.. It sure surprised me, I was almost ashamed to use it when I showed it off to a friend.. lol. But it’s a new age..
Thanks for the comment on my system.. After I downsized and sold off my big rig and moved, I started over again and went for something ”smaller” yet still very capable. the Daedalus are easy to live with And setup compared to the Vonschweikert’s I had.. I also gave up my tube equipment for SS.. All sand now.. Something I never thought I would have owned.. but the Pass gear is pretty good stuff and I don’t miss the tube hassles I was having.. it’s also simpler, but not too simple.. Enjoy the music !