Battery Power for our Systems?

[RoyB]

I've been thinking....Dangerous I know! On another forum a fellow was reporting that he was using a Portable Power Supply (A LiPo battery in a box with a Pure Sine Wave Inverter) to power his system. He suggested that it got him totally away from the "Grid" and all its noise and distortion. I've done a lot of work and built a number of these +Solar Generators" for the Overlanding RV crowd and I know the best of the best still has issues with the inverter phase of the operation when used with delicate electronic equipment. This morning I'm reading a review in Stereophile about the "FE - HYPSOS"....A stand alone power supply to be used in place of supplied outboard power supplies. Very interesting article, BTW. So...I was thinking, with Li battery technology exploding as to amp-hours and limited voltage drop over its discharge cycle, would it be practical to build HiFi equipment that runs on 12, 24 or 48V DC and do away with the whole AC to DC conversion in the equipment. You would charge up your LiPo battery at night from the grid, or during the day while at work off solar, and run your system for hours when needed. Pure, Clean, Voltage stable DC power...No grid connection during play. Wouldn't this drastically reduce the cost of components if they didn't need elaborate power supply filtering etc? LiPo batteries are relatively light weight, have huge amperage discharge available and have life spans of 20+ years with the ability to be recharged thousands of times. Current Lithium batteries don't catch on fire like older batteries did...So don't go there. One LiPo power supply unit could run the entire system rather than multiple power supplies in each unit. Yes-No.....Go back to bed?

I'm looking at it as not only a noise/performance issue (as many folks have really horrible grid electricity or live in apartments with outdated infrastructure)......But also as a manufacturing cost savings and weight saving for shipping. No heavy toroidal transformer and extra heat sinks. Shipping cost have become a huge part of the cost of manufactured goods.

 

[JeffS7444]

If your devices are built around a standard like USB Power Delivery, great. What makes this approach so useful is that you can standardize on a single type of connector, while voltage and maximum available power is negotiated between device and power supply.

 

[voodooless]

DAC’s reach -120 THD+N with your noisy distorted AC, Amps can also almost get there. Why would you need a complex battery system?

 

[jtwrace]

It's so ridiculous. Buy properly engineered equipment and just plug it into the wall (or in my case into a Zero Surge unit) which then plugs into the wall.

 

[Blumlein 88]

There is little to gain with well made electronics as they are. I also do not think you can save any money this way. It can of course be done. I mean a Tesla power wall can power your house much of the day if you wish it.

 

[voodooless]

But also as a manufacturing cost savings and weight saving for shipping. No heavy toroidal transformer and extra heat sinks.

We have Class-D amps and SMPS’es now, cheap, light and efficient.

 

[MRC01]

Good advice so far - well engineered power supplies isolate the noise & hum, producing clean audio output. No need for batteries.

However, one area I found batteries useful is DIY - building your own gear. When I built a phono head amp, it was easier and cheaper to power it with rechargeable batteries, than to have a power supply. The amp required very little power so a pair of 12 V, 7 amp-hour gel cell batteries powered it for more than 100 hours of continuous use per charge.

 

[DanielT]

But to plug in a battery pack? Hm, would not this work for DAC Topping E30 for example? I've never thought about. I'll test that.

Maybe there will be a problem with grundig then, but hm ....?

Ground (electricity) - Wikipedia

en.wikipedia.org

 

[voodooless]

But to plug in a battery pack? Hm, would not this work for DAC Topping E30 for example? I've never thought about. I'll test that.

The 2A output should work just fine.

 

[DanielT]

The 2A output should work just fine.

Thanks for the response. Another gadget to try. He he.

 

[audio2design]

I've been thinking....Dangerous I know! On another forum a fellow was reporting that he was using a Portable Power Supply (A LiPo battery in a box with a Pure Sine Wave Inverter) to power his system. He suggested that it got him totally away from the "Grid" and all its noise and distortion. I've done a lot of work and built a number of these +Solar Generators" for the Overlanding RV crowd and I know the best of the best still has issues with the inverter phase of the operation when used with delicate electronic equipment. This morning I'm reading a review in Stereophile about the "FE - HYPSOS"....A stand alone power supply to be used in place of supplied outboard power supplies. Very interesting article, BTW. So...I was thinking, with Li battery technology exploding as to amp-hours and limited voltage drop over its discharge cycle, would it be practical to build HiFi equipment that runs on 12, 24 or 48V DC and do away with the whole AC to DC conversion

I would almost guarantee that "fellow" also extols the superiority of turntables and his listening room is an acoustic mess. I would guarantee he does not own a measurement microphone, let alone know how to use it, his frequency response is likely all over the place in the bass, does not believe in room correction or equalization, and probably has his cables on replicas of the Empire State Bridge. He probably think Trump won the election too.

 

[egellings]

Batteries are meant for portability (if not used as a whole house backup like the Power Wall). Filtered & regulated DC from a rectifier can work every bit as well when portability is not an issue. By portable I mean, carried where there is no AC power available.

 

[levimax]

I played around with the batteries for my DAC pre-amp and electronic crossovers and as stated above it works fine but you can get just as good performance with a good AC power supply so it is not really necessary. To get batteries working right you still need large caps for filtering and more importantly to reduce the internal resistance as seen by the component. The other big issue I ran into was getting a good "split rail supply" which is required internally for any amp or pre-amp. Many people use 2 batteries in series and take the common from the middle of the 2 batteries but since batteries are not identical and age differently you will end up with unequal voltage on your split rail supply which is not good. The other solution is to build a "voltage splitter" which is not too hard for line level stuff (certainly adds complication and reduces efficiency) but gets really hard for high power applications like a power amp. Batteries seem like a good idea at first but the more you dig into it the more it does not make sense. If you want to play around with DIY stuff it can be fun though.

 

[DanielT]

Dual 9 v batteries that drive a pre amp with motor OP amp 5532. Works probably good (if the solder is nice, plus short signal paths).

Perfect for a beginner in DIY, to learn. This way you do not have to plug in and get power from the wall socket.

Yes, of course I'm talking about myself. But more people can test that DIY.

Edit
Fun to read about how OP amps work, when testing that DIY. Alps volume pot fixed. The project is rolling on, so far. Just need to get hold of such a damn OP amp holder. .Whether it will sound good or not.., I do not care. Good sound is not the purpose of the project.The purpose is to learn.
Well it's OT, in another thread so..

 

[DVDdoug]

"If it ain't broke don't fix it." If you have hum or a ground problem then an isolated DC power supply could help but pro studios get-by just fine with regular AC power.

would it be practical to build HiFi equipment that runs on 12, 24 or 48V DC and do away with the whole AC to DC conversion in the equipment.

No. Different things need different voltage (and current) and many amplifiers have positive and negative internal power supplies. The most practical thing is standardized AC wall power with plenty of available current.

It's also easy to step-up or step-down AC which is why Tesla's AC beat-out Edison's AC. (With modern electronics it's fairly cheap & easy to step-up or down DC.)

Wouldn't this drastically reduce the cost of components if they didn't need elaborate power supply filtering etc?

in some cases yes, but lots of devices need more than one internal voltage, and for example "regular" car amplifiers can use the 12V but high-power car amps have an internal voltage booster.

 

[egellings]

That little battery powered phono stage can work really well. There are no ground loops to worry about, for one thing. It's completely isolated from the AC line.

 

[tvrgeek]

Battery power and a pure sine wave inverter will for sure prevent any snakes from squeaking.
We went through the direst batter power BS in the 80's. What it proved is how noisy a battery is. If you are so incompetent ( not stupid mind you, but without the knowledge, to make a decent supply and have no ground loop problems, find another hobby or hit the books. It tain't hard!

Any piece of consumer equipment that can't be pugged into the wall, or at most a DC blocker and basic line filter, is a piece of junk and you should toss it and get something at least half decent.

This subject, and all the falsehoods around it, have popped up on several forums. I blame COVID. People not working and inventing solutions to problems that don't exist. Ya got a ground loop? Find out why and fix it. Science, not y-tube experts and cubic dollars.

 

[DanielT]

.... What it proved is how noisy a battery is....

Aha! Thanks for the information. I did not know that. You learn. As it is called.

 

[levimax]

We went through the direst batter power BS in the 80's. What it proved is how noisy a battery is.

Except batteries are not noisy https://tf.nist.gov/general/pdf/1133.pdf. While I agree you can get an AC power supply to do anything batteries can and battery power is not practical it is simply not true that batteries are noisy.

 

[warnerwh]

Amir did a great video on AC noise and distortion: