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Fully DC-Powered Home Audio System

I’ve been experimenting with battery-powering various pieces of my audio system for the last 6 months. It started with front end gear such as sources and preamps and I got good results. Due to poor in-wall wiring which greatly limits current delivery to my amplifiers (and the lack of time to run new wiring), I was compelled to try my hand at battery powering my speaker amplifiers. These were the last components to be powered by batteries, effectively making my system 100% DC-powered, off-grid.

What I have noticed with battery power is that the sound is very organic and natural which makes certain musical pieces like cello and piano works sound wonderful. With faster paced music that has lots of “dynamic slam,” the music seems a bit tamed. A tad boring.

It seems that battery power has a sonic signature. I’m wondering if it is just an intrinsic quality of “battery sound,” or if the “dynamic slam” can be improved upon. A few ideas that have crossed my mind include using larger batteries or incorporating large capacitors somehow.

Really I think what I am asking is how do you make battery powered gear have the slam and authority of good AC-powered gear while maintaining the naturalness and off-grid benefits that batteries offer?

Thanks!
128x128mkgus
7 responses Add your response
millercarbon's avatar
millercarbon
12,531 posts
 
The current carrying capacity of wire varies tremendously with voltage. That is why car battery cables are so big. You're hearing the clean power of the batteries, but unless they are very high voltage, or you're running super thick gauge wire, you will be losing a lot of dynamics in the wire. 

Did you do your voltage/current/wire gauge math?
jjss49's avatar
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jjss49
6,612 posts
 
you will need one of elon's power walls
oldhvymec
5,101 posts
 
A good cap bank, in the mix, would do it.
So would a good voltage maintainer (300.00), and no batteries...

Kinda funny, automotive guys drag a generator behind their car stereos so they have enough power to run the things, at show.

Home stereo guys drag batteries, into the mix, so they can, do what?
Just wondering? I can't figure that one out.. I can see off the grid, I can see if your on the road. But at home, I suppose it's fun to tinker with, though.

Regards 
mkgus's avatar
mkgus OP
324 posts
 
I did do some math for the wire gauge. The run from the 12V battery to the amplifier is only 3 feet. Originally I ran 8 gauge but it sounded a bit strange (psychological?) I’ve got 12 gauge hooked up now. What’s your rule of thumb for an acceptable voltage drop as a percentage? The amps are rated for about 400 watts RMS but I doubt I push them that hard. 
400 watts is 33A at 12V. Three feet of 12 gauge is a 2.62% voltage drop. 

I wonder if anyone is using a Tesla power wall for audio. I hope so. 

People have different reasons for using batteries but the main one I see is getting off the dirty grid power and feeding pure, clean DC to your components. It’s quite noticeable as a layer of hash and digital glare is removed. Although the cost appears to be a more laid back, less dynamic presentation. A cost I hope can be mitigated. Maybe it can’t. 
mkgus's avatar
mkgus OP
324 posts
 
Quick update: The “restricted dynamics” I refer to above has been improved upon with a change in my preamp. I believe I had an impedence mismatch which made things sound “off.”
mijostyn's avatar
mijostyn
8,570 posts
 
Battery power makes a lot of sense for audio equipment. My favorite phono amp is battery powered. For power amplifiers the battery is essentially a very large capacitor assuming it is a big battery. Heavy gauge wiring is mandatory. Theoretically this could make an amp more dynamic. You don't have to worry about voltage aberrations either. Not sure how big a battery you would need. My system can produce 9600 watts and I would want a battery system that would last at least 8 hours. It should charge automatically when the power to the amps is off. Sounds like a lot of lead acid batteries. Anybody know how to figure out how many batteries you would need? Also , you would need a voltage dividing network to supply the right voltage to each unit. Some units like the JC1 amplifiers have multiple power supplies probably making different voltages just to make life difficult. You could use multiple Furman UPS units. They produce very clean AC and you can daisy chain as many batteries as you like. All you have to do is turn off the power to the UPS and it will light up.
patrickcarey
21 posts
 

On occasion I run my entire stereo from a Yeti 1000x.   Depending on the equipment, cabling and music there is a usually an audible difference in the quality of the sound.  Sometimes it is subtle, sometimes the difference is impressive.  

Interesting that my digital sources are generally most improved by running from a battery, and the power amps not so much.  

Next stop a synchro Uni DC filter from Isotek.  

And sound engineers have experience and are willing to comment ?

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