Best 5V SMPS ?

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All of them are compromises.

It's again a matter of design and implementation quality.

You get good linears, you get good SMPS, you get good battery supplies
and not to forget you get very good supercaps supplies.

You'll also find bad versions of all of them.

And then it's a matter of application. Different applications require different
power supplies.

All this has multiple dimensions.

And then you gotta combine many of them.

And. If you look at it from a wider angle. Your whole audio system is very complex.
Groundloops, cabling, etc. matters.

And of course your house environment also matters.

You've got a nice journey in front of you. :D

Good luck.
 
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iFi grounding adapter

Thanks, Chris, I will try to get one pair, and compare the IFI with the battery again.

iFi can supply this for ~$13 inc shipping in the US. Resistance to ground is ~ 15 Ohm.
 

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My idea would be to keep the ground impedance as low as possible.
And I'd also try to avoid creating new antennas. Obviously there's a catch.

All these el-cheapo plugs and connectors are IMO all but optimal.

I do have all my stuff (amp/dac/pi - all sitting side-by-side on one board) stargrounded via Wago terminals - without connecting them straight to earth.

Perhaps I try that ground-wire idea one day.


But before you start doing anything. Make yourself a drawing about the grounding-scheme of your entire system.
It's quite beneficial to have the full picture of what you've right in front of you on paper.
 
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It is rather interesting findings on Allo adapter, the IF I adapter, and a 10000mAh Battery bank from MI.

No doubt that AC power supply such as Allo, IFI comes with inherit noise. But pesonally, i always have doubt battery bank such as 10000mAh Battery bank from MI are noise-free; although they are from DC power supply, however 3.7~42v Li-battery undergo switching mode DC-DC to bring up to 5v USB power, such approach inherently cause switching noise output as well.
Perhaps, we have been looking at the picture only from the pov of from noise. To reproduce sound, especially bass, current is needed, i.e. a big store of electrons. It can be said that power amp needs it more than a dac, but Allo has been using SC on their DACs near the OP stage.

Maybe a battery provides electrons better than psus so sounds richer !

Just my 2cents ...
 
It is rather interesting findings on Allo adapter, the IF I adapter, and a 10000mAh Battery bank from MI.

No doubt that AC power supply such as Allo, IFI comes with inherit noise. But pesonally, i always have doubt battery bank such as 10000mAh Battery bank from MI are noise-free; although they are from DC power supply, however 3.7~42v Li-battery undergo switching mode DC-DC to bring up to 5v USB power, such approach inherently cause switching noise output as well.


Yes agreed, however battery banks have one major advantage. No connection to the mains , true galvanic isolation. As such there is no leakage currents , no low frequency noise. Yes there is sw frequency noise and ripple but thats rather simple to clean using inductors and ldos.
 
@cdsgames

I'm wondering if that new SPMS can be taken out of the case - without lowering its performance.

The reason I'm asking:

I currently have 3 iFi iPowers running. These pretty much occupy my valuable HiFi powerstrip already.

I'm wondering if I could take out the electronics from 3 of yours and make a 1x230V-in and 3x5V-out to build my own multi-5V-out supply.

iFi makes things rather complicated to accomplish something like that.
 
One more.

I'm also working on a setup that lets me handle all my powersupplies remotely.

Basically I'd like to turn on and off my system by pressing a single "button".

Currently nobody else then me can start-up my system.
Starting numerous powersupplies in a different order just can't be expected to be done by the rest of the family. :D

That's why I need one big button.

Basically I'm thinking of a PI and a relay extension board to accomplish this.
This way I need to have access to all mains cables.

However. I'm wondering if such a SMPS - the one we're talking about -
could also come with an input that could be directly attached to e.g a PI GPIO. This port then could be used to turn such a device on and off at a very low effort.
Something like that would preparing quite well for house automation purposes as well.
What do you think about that idea?
 
So,
linear supplies have diode noise,
SMPSs have switching noise,
Battery banks have boost convertors,
Duracell is 1.2V
Car battery is 12V, 2V x 6,

So where do I get clean & pure 5V dc from?
[emoji53][emoji53]

We could use a 6V motorcycle battery with 1uF polyester 250V from plus to minus. We might use 1 or 2 forward biased silicon diodes to give circa 5V. The 1uF could be after the diodes to get the best speed and noise. A forward biased diode in theory has no noise. It will have a little, It's not switching noise. Current should be good where it needs to be.

Capacitors can be charged using a voltage comparator switch over if the current isn't too high. The charger never sees the load as the capacitor in use swaps with the one or bank on charge. If the clicking of a relay is OK it can be that simple. The NE555, LM339, LM324 all might be used. I like the LM324 as it can both sorce and sink current up to about 20 mA. It looks very like the LM339 except it is an op amp. Although very poor as an audio device it is great as a stand in comparator. Usually a little hysterisis is added as shown in the application notes to stop jitters etc. If the current use is fixed the comparator might be just a NE555 and relay pair. The caps switched by time alone. If we went from 5.5 to 5 VDC that might be fine.
 
My experience with iFI ipower is that it does alter the SQ in a way that you lose the lower end. My setup is a 502 dac pro, powered separately from the pi. Initially I had ipower connected only to the dac and a usb charger for the pi. With that config, I could hear stronger bass notes. Yesterday I decided to get another ipower for the pi expecting better SQ but was sorely disappointed that it lost most of the lower end, lacking so much bass to a point that the music wasn't as enjoyable. It's unbelievable how much a power supply can alter the SQ of a rpi streamer. I'm gonna get the official power supply for the pi and see if it can balance out the highs and the lows.
 
It should with a little care be possible to make any PSU sound good. It possibly needs more test gear than people want to buy. For me it comes with the job. Even a lead acid battery ( accumulator ) can sound poor. A 1uF 250V polyester can cure that used in parallel. If you think about it nothing on the planet should beat a lead acid battery.Tons of current and no fancy charging.

If a PSU lacks bass and is of the usual 1 amp capability it should be able to drive a preamp type device. When bad sound the most likely problem is complexity of grounding or too thin a ground cable. Conversely the type of cable if too thick can make for a dull sound. No real idea why as skin effects shouldn't be important as DC and handled by local decoupling next to chips ( Litz effect in it's original meaning by Tesla, his own skin ). Sometimes what sounds like poor bass is in fact radio frequencies entering the circuit causing false DC reference points. All of this says a linear supply is best even when digital circuits. None have to be large although large often sounds best. As far as I can see a large linear supply is also a radio frequency filter. Naim Hi Cap was just a big toroid and LM317 regulator. It sounded better than the already large Naim SNAPS PSU. The difference in sound was like a very much more powerful and expensive amplifier, slightly weird as the power amp was not changed, only the preamp. Friends often said Naim were crafty to do this.
 
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