Interesting lecture about noise, LPS, SMPS and batteries with Rob Watts, Digital Design Consultant, Chord Electronics:
Torben
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Following a conversation with Rob when the Hugo first came out, I have always powered mine with an Optima Yellowtop battery.
Oh Bugger, have I got to try car batteries now?
Just wondering HTF do I get 12v DC into my amps 
A set of jump leads should do it!
As they involve cable I expect there to be multiple reviews comparing Halfords jump leads to other motoring brands.
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Interesting.
How do you charge the battery and regulate the output ? Do you use 12V, 9V, 5V ???
Must say I do not hear a differance between a WELL designed SMPS against a LPS.
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I have a dedicated solar panel that keeps the battery charged, with a voltage regulator between the Optima and the Qutest.
Another engineer with the same conclusion…
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I am a tinkerer … which includes having a go at fixing stuff! Have had hi-end gear that eventually needs repair; so I take the lids off and SMPS not LPS 50% of the time. That said had some hi-end kit I now reflect was not hi-end SQ for the money (grrr…) Not sure I hear a differance.
Had a top-end streamer; took the lid off and its SMPS power supply had blown. $40 fix.
Have a top of the range very well reviewed 4K video disc / Audio transport ; its power supply blew and it was an SMPS. With a multi-meter, T7 tester, soldering iron, time and new hard to source diode fixed it for $8.
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I have already known this information a long time ago. Unfortunately, there is no SMPS designed specifically for audio nor there is any viable way to use a car battery in my living room. Sorry, I have a wife and 2 kids, and I cannot turn my living room into an experimental lab. Therefore, the only solution I have left is Linear PS designed for audio.
That’s not the right way to look at this. Take for example the power grid. It wasn’t designed specifically for vacuums or specifically for fridges. It was designed so that it can be used to power pretty much anything that requires electricity. A good engineer doesn’t design appliances that require a specific type of power grid; they design them so that they can be used with the existing mains. Same with audio: good engineers design devices that can be used either with the mains or with any PSU that gives a certain voltage (or range of voltages) and a certain minimum current (or power). Those devices have internal voltage regulators that make them work with practically any kind of PSUs.
The reason batteries designed specifically for cars work with audio is not a coincidence: they are, at the end of the day, “batteries”, so they can be used with virtually anything that takes 12V DC. Does it matter if they use lead-acid instead of Ni-Cd or Li-ion? Of course not.
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What you said sounds perfectly good in theory only. In reality, this is not the case. Most SMPS in the market are made to maximize overclocking capacity with a minimal budget. They mostly use cheap components and have a limited life span. I have waited many years, and nobody has developed a properly designed SMPS. Sorry for bursting your theoretical bubble!!
Have a look at Mean Well medical power supplies
Torben
I knew of those!! they will require some customization. The result is not guaranteed. And they will turn my living room into a lab, which is exactly what I want to avoid. If I am single and live in a cave, then yes I will be more than happy to try them out.
Than have look here:
Torben
If you buy a good DAC that plugs into mains and has an internal SMPS, that’s a properly designed SMPS. Or, if you buy good DAC that comes with an SMPS wall wart, that’s a properly designed SMPS. If such a DAC worked better with a different PSU, then it would not be a good DAC, because there is nothing an external PSU can do better that the DAC couldn’t also do internally. There’s nothing theoretical about it.
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It is a possible solution to drive some accessories. What I am looking for is true ATX PS for computers. Those exist, but they are either very expensive or being made in small batches and sold out immediately.
I have a very expensive DAC ($10,000) already running on its battery. That area needs no further improvement. My bottleneck is the ATX SMPS for my PC which acts as a transport. There is no possible design to replace it yet.
Performance of digital transports has nothing to do with PSUs. Upgrading PSUs for PCs, modems, network switches etc. makes absolutely no sense. The analog domain is different, and you do need to take some precautions there to deal with voltage noise and stability, but that starts at the DAC.
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… and do you have any data to back up that claim?