Thread: Battery-powered server or battery power supply?

Originally Posted by ggking7

Are there any music servers out there powered by a battery supply? Is there a computer battery supply available?

Why do you want to use a battery for your server? Do you have frequent power outages, or do you want to use it somewhere where you don't have mains power available?

Some people use batteries for their players/clients/DACs for sound quality reasons, but as long as your server is galvanically isolated from your player the power supply of the server is not really a factor in sound quality.

What kind of player/client are you using? How will it be connected to the server - wireless or wired ethernet?

Several users have done this with low power servers, most recent example is here.

For a LOT more money I've heard some good things about Red Wine Audio Black Lightning.

Originally Posted by souptin

I think the op is thinking in terms of "server" being the player, rather than a file server located elsewhere on the network. Personally I wish the term hadn't been commandeered into the audio dictionary (always struck me as a marketing ploy to give the playback computer a more important sounding name, which in turn would obviously improve sound quality without actually changing any parts *cough*).

Agree. Wish manufacturers would stick to a consistent terminology. I was assuming the terminology standardized for UPnP and other distributed multimedia systems, where the server is the device that streams the data over the network to the client/player.

Out of interest, does wired Ethernet automatically include galvanic isolation?

Usually, but not always. The input circuitry of an ethernet tranceiver is a balanced (differential) circuit isolated from ground and power supply (often with a transformer referred to as "magnetics"), but with a shielded cable (cat6), the shield can form a ground path between the devices.

Originally Posted by ggking7

I'd like to try a battery power supply to see if it makes a difference for sound quality. I realize galvanic isolation would negate the need for this, but my Proton is not isolated, plus I've read that galvanic isolation can have a negative impact on the sound (which is usually/always outweighed by its benefits).

I think it would help if you could describe your setup to us - clearly we aren't talking about a music server in the uPnP sense here. It seems what you have is a (desktop?) computer connected (via USB?) to a Wavelength Proton DAC - is that correct?

I would give an RWA Black Lightning a try, but I don't see how I'm supposed to go from the Black Lightning to all the voltages and harnesses necessary for a motherboard. Do you?

I guess the easiest solution would be a special PC power supply designed for car use - there are a bunch of ATX power supplies that work from 12 V, and can be battery-powered from a motorcycle battery - such as the ones from these guys: small PC ATX power supplies with 12V or 6-24V input

There will still be switching regulators between the 12 V and the logic supply voltages (5 V and 3.3 V) in the power supply.

A lot depends on what kind of PC you have.

There are a lot of motherboards these days that will work off a single DC connection instead of or in addition to a typical PC style power supply with multiple voltages from a single harness. Many Intel Atom boards support this, as do boards based on similar classes of CPU. The boards recommended for CAPS V1 and V2 both are in this category. This is also important in the sense that the vast majority of PC power supplies also include fans, which is something you want to avoid.

Originally Posted by ldolse

There are a lot of motherboards these days that will work off a single DC connection instead of or in addition to a typical PC style power supply with multiple voltages from a single harness.

Yes, especially mini- and micro-ATX form factor ones. Keep in mind that they still have SMPSs - they are just on the motherboard. The logic chips need 5V and 3.3V at reasonably high currents. My personal opinion is that a well-designed SMPS is actually better than a linear regulator from a SQ point of view, but people who want to use battery power to avoid perceived power supply noise might want to think about the implications...