Linear Power Supply for a MacBookPro

[Gilles]

Good day to all,

 

I read lots of posts on linear power supplies and, if I am not mistaken and my memory does not fail me, I find that the vast majority deals with Mac Minis.

 

I would like to know if it is feasible to connect a linear PS to a MacBookPro and, if yes, is it as simple as plugging the DC cable into the MBP's MagSafe port, or does this require internal mods to the MBP?

 

Comments and links to existing threads on PSs and MBPs will be greatly appreciated.

 

Thank you very much in advance.

 

Gilles

[satbaba]

no answer ?

[One and a half]

The psu for the notebook contains circuitry to charge the battery. It is then a little more complex than a standard fixed voltage supply.

[Nes]

Just run your MacBook of the battery, no need for a LPS at all.

[Gilles]

Thank you for your post Satbaba, your two-word question prompted more replies within a few minutes than my post did in a bit more than one month!

 

Thanks also to One and a half and Nes.

 

I read about the Keces and Teradak power supplies, as well about other brands commented on by other members and, after an exchange of emails with Paul Hynes, ordered a PSU from him a few days before Christmas. I should receive it sometime in April and will post comments on the change it will bring to the vintage sound produced by my old Luxman.

 

I was not planning on doing this now, but rather when I will post comments on his PSU, but as I am posting something now I wish to commend Paul for his generosity in answering my questions in detail. Since I am not knowledgeable in power matters, as in many other technical matters, I would have been satisfied with shorter answers from Paul, but he took time to write long emails to make sure things were clear for me. This created a reassuring feeling.

 

So...next post from me should be sometime in April.

 

Cheers,

 

Gilles

[satbaba]

Thanks Gilles ,

waiting

[Flange]

Gilles

 

I have a Paul Hynes SR7 linear power supply to my Macbook Pro and it made an amazing difference in lowering the noise floor allowing better low level detail retrieval and imaging.

 

I sent Paul the magnetic Macbook connector and he incorporated into the power supply.

 

Stick with Paul as his build times are lengthy but his products are first-class and well worth the wait.

[Gilles]

Flange,

 

I am obviously happy to hear that you are very satisfied with your Hynes SR7 PSU...this adds to my eagerness! I forgot to mention that I also ordered an SR7.

 

Paul now has a source for MagSafe connectors, no need then to send him ours.

 

Best,

 

Gilles

[wgscott]

Just run your MacBook of the battery, no need for a LPS at all.

 

[Nes]

wgscott, not sure I understand your "non-believer" post. I understand why you'd want (there may be exceptions though) an LPS vs. a switching power supply in for example a Mac Mini or other non-battery operated PC.

 

However, the OP is talking about a MacBook Pro laptop which does have a battery. I was suggesting if you take the MacBook off the charger while listening, you would not need a LPS. Or are you saying that the MacBook Pro attached to an LPS charger would perform better than running on it's own batteries?

 

I'm grossly overgeneralizing here but (without my own testing, just from what I gathered from reviews, posts etc) up until now I have assumed Battery > LPS > SPS.

[Jud]

Bill is saying you will be "shunned" by believers in LPSs for pointing out the MBP has a battery, so what's the point?

[Nes]

Haha, okay Maybe it was too obvious the MacBook has a battery, silly me for pointing it out to the OP.

[wgscott]

Thanks, Jud!

[wgscott]

Haha, okay Maybe it was too obvious the MacBook has a battery, silly me for pointing it out to the OP.

 

No, I think it was the single most insightful post on this thread.

[Chopin75]

The use of battery alone is very interesting. I wish this thread would continue, so am trying to spice it up again. My question is, did the LPS improve SQ compared with battery alone or the improvement is mainly when compared with stock Apple PS? 

There has been a theory that battery will outperform any AC/DC supply and in fact Channel records and Naxos apparently use battery run equipment only. The LPS manufacturer will tell you otherwise that LPS is way better than battery PS, like from Mojo but that is because they want to sell you the LPS. I understand that for MacMIni it makes sense to do DC LPS, but is it needed for Macbook Pro. 

Currently I have a Macbook Air. Running on battery alone clearly sounds better but if you add USB devices like iFi galvanic that requires some USB power, there is reduced dynamics and details & air, all becomes too tame. This is eliminated with separate power supply to the USB device like using iPower/idenfender, So running on battery using this combination works great: 

 

Macbook on battery --> idefender + ipower DC supply ----> iFi galvanic ----> DAC 

 

Though perhaps when I run audirvana with multichannel  + playing ISO, or DSD converting to PCM (because my DAC cannot do M-Ch DSD) then maybe I would need more power with AC adapter. 
I  am wondering if using external LPS for Macbook may give better SQ than battery alone. Bear in mind I am testing only on Macbook Air, 1.8 Ghz only. A Macbook pro with 2.8 Ghz quad core may be a different story and may not need any external PS. 

Then latest Macbooks use USB-C as PS plug-in instead of the magnetic one so it is easier to just use an adapter to connect to any LPS, I presume. 

 

 

 

[mansr]

3 hours ago, Chopin75 said:

I  am wondering if using external LPS for Macbook may give better SQ than battery alone.

Whether on battery or external power, a multitude of switching regulators are used internally. Running on battery has the advantage that ground loops or other evils coupled through the power supply are impossible. An external power supply may or may not provide such isolation. If it does, a good one can have lower noise than the battery. No simple answers, I'm afraid.

[nkbg]

I have a 2015 MacBook Retina (USB-C) and 2014 MacBook Pro (QuadCore i7). Music is stored on a NAS or Tidal. I output Ethernet from the laptop directly to a Devialet D400 via a pair of FMCs where the downstream one is powered with an Uptone JS-2. To my and my buddy’s surprise each laptop sounds different and the 2014 Pro sounded better. 

 

Recently, I found a used MusicLinear power supply that outputs 20V over USB-C PD and via MagSafe. Seems like the indiegogo campaign never shipped but there was one available on eBay so I purchased it just to try it out.  

 

The power supply made a clear difference on both laptops. Better bass and clarity in upper mids and highs were easily discernible.

 

Planning on keeping the power supply for a while. 

 

N

 

 

 

[Chopin75]

I see, nkbg, did u try comparing battery run Mac vs LPS run ? Also is fhe Macbook pro 2015 quad core or dual core ? It seems quad core runs better. 

[nkbg]

The Pro is a quad core.

 

I’ll spend some more time comparing battery vs LPS and post.

[matthias]

On 6/15/2018 at 5:47 PM, nkbg said:

The Pro is a quad core.

 

I’ll spend some more time comparing battery vs LPS and post.

 

Hi, trying to resuscitate this interesting thread.

 

@nkbg Did you compare battery vs LPS?

 

What about new LPS for MacBook Pro with USB-C power connector?

 

Thanks

 

Matt

[nkbg]

I did.

 

I have a Music Linear LPS that works with both MagSafe and USB-C MacBook Pro. It it a clear step up in SQ. Also, running Euphony improves it further.

 

I've since moved to a dual NUC setup and the LPS will go on sale.

[gmgraves]

On 12/2/2013 at 12:16 PM, Gilles said:

Good day to all,

 

I read lots of posts on linear power supplies and, if I am not mistaken and my memory does not fail me, I find that the vast majority deals with Mac Minis.

 

I would like to know if it is feasible to connect a linear PS to a MacBookPro and, if yes, is it as simple as plugging the DC cable into the MBP's MagSafe port, or does this require internal mods to the MBP?

 

Comments and links to existing threads on PSs and MBPs will be greatly appreciated.

 

Thank you very much in advance.

 

Gilles

Well, the power supply requirements between a Mac Mini and a MacBookPro are quite different. The PS in a Mini powers the computer directly, but the PS in a laptop merely charges the computer’s battery. It’s the DC battery that powers the MBP. I doubt seriously if there would be any difference between a linear power supply and the MBP’s battery charger. 
HOWEVER, The PowerBook has feedback to the battery charger to keep the charger from overcharging the battery. Notice that the magnetic connector on the MBP has an orange led that’s lit when charging, but at some point, when the battery is fully charged, the light turns green. If you bypass this charging monitor function, you will ruin your battery very quickly.

[Ralf11]

why not do the cheapest and/or easiest option first?

 

use an external DAC that is isolated for noise, or use an isolation device to feed the DAC

[gmgraves]

1 hour ago, Ralf11 said:

why not do the cheapest and/or easiest option first?

 

use an external DAC that is isolated for noise, or use an isolation device to feed the DAC

The easiest is, of course, to connect to the outboard DAC is with optical. Depending on the year this MacBookPro was made, the headphone jack doubles as a Toslink port. The newest MacBooks have dropped that feature, but the series before the latest one still has it. You need an adapter that goes from a 3.5 mm headphone plug-like shape to a regular Toslink female, or a cable that has the 3.5mm connector on one end and a normal Toslink connector on the other. 
The optical interface isolates the computer from the DAC both galvanically and electrically. It is limited to 96 KHz but that’s what most Hi-Res is anyway.

[ferenc]

I am using my 15 inch 6 core i7 MacBook Pro with and Elgato Thunderbolt 3 dock which has a standard DC connector. I power the TB3 dock from a locally made 20V, 10A linear power supply. This way I can power any device connected to the dock, linearly, not only the MacBook Pro through its TB3 connector. Works very well.