Chemical energy is to slow for audio. Any well sounding battery powered amp has additional, huge capacitor storage, more than a transformer/ mains driven one would have or it will sound weak and lifeless. The idea is nice, but it does not work for sound quality.
Battery powered amp, pre.amp, DAC, CD -player, all has been done,many times and did not have the desired effect.
So if even a cheap SMPS instead of expensive, complicated battery cells, connected to the same power supply, sounds better, what is the value?
There are some good pre-amps with battery power (lead, Nicad and NiMh) out there, but regular powered ones are always better. Has been tried again and again, starting decades ago. No new idea...
Battery powered amp, pre.amp, DAC, CD -player, all has been done,many times and did not have the desired effect.
So if even a cheap SMPS instead of expensive, complicated battery cells, connected to the same power supply, sounds better, what is the value?
There are some good pre-amps with battery power (lead, Nicad and NiMh) out there, but regular powered ones are always better. Has been tried again and again, starting decades ago. No new idea...
Hi,
I would like to understand in a slightly more formal or measured way how this belief exists.
Basically, first thing as I see it is if you rely on capacitors to support a switch mode, the same amount of capacitiance will acheive the same result on a battery, unless the sag on the battery is slower than the time constant of the attached capacitance (to the level of volt drop decreed aceeptable). A lithium battery is plenty fast compared to some 10's of thousands of uF.
From my industrially deaf ears, I only hear better sound from battery powered class D amps I have used vs SMPS, no power supply noise at all is the first thing.
Please feel free to go into as much technical detail is needed, I am an electrical engineer specialising in industrial design and would like to understand if I am missing something.
Thanks.
Thanks.
I would like to understand in a slightly more formal or measured way how this belief exists.
Basically, first thing as I see it is if you rely on capacitors to support a switch mode, the same amount of capacitiance will acheive the same result on a battery, unless the sag on the battery is slower than the time constant of the attached capacitance (to the level of volt drop decreed aceeptable). A lithium battery is plenty fast compared to some 10's of thousands of uF.
From my industrially deaf ears, I only hear better sound from battery powered class D amps I have used vs SMPS, no power supply noise at all is the first thing.
Please feel free to go into as much technical detail is needed, I am an electrical engineer specialising in industrial design and would like to understand if I am missing something.
Thanks.
Thanks.
All you miss is 40 years of HIFI development. Battery driven high end has been tried a thousand times, but never worked audible better than "usual" stuff.
You are free to build whatever you believe is best for you. If it sounds better to your ears, fine. If it makes you feel happy, perfect.
Nothing is easier than connecting a bunch of LiPo chunks or what ever is your favorite.
Good luck!
You are free to build whatever you believe is best for you. If it sounds better to your ears, fine. If it makes you feel happy, perfect.
Nothing is easier than connecting a bunch of LiPo chunks or what ever is your favorite.
Good luck!
Some old laptop batteries (18650) can struggle with 5-7 ampere. Make sure to find the spec through the series number on cells or battery casing. I bough some new Samsung batteries that couldnt handle 7A. There is night and day difference between 18650s. I've tried running 5 18650 in series with a tpa3116 and it worked fine until the end were voltage drop became noticable as less bass.
I dont think this solution will play better than a regular good psu if you dont use new high current batteries. It will just be decent since the esr of a single row of used batteries will be high. The risk is going up by a lot with older cells! If one fails down to 1-2V you will overcharge that cell and all that energy will heat up that failed cell. In all professional eboards there is a temp fuses to keep cells from blowing up. And battery packs in eboards fails quite often. A bms is a cheap solution and needed because of the relative high charge rate you plan to use.
Impishbynature, a good 18650 battery has the same ability as a huge capacitance and very low esr vs supercapasitor. I tried to build a booster psu for an rc car once. I learned that 4.2V stepped up to 11.1v and a lot of capacitance wasn't in the same league as a tiny lipo battery for buffering the 11.1V before going into the speedcontroller. Supercaps must be 10x better to compare to a lipo of similiar weight. Thats why no one uses supercaps in cars..
I dont think this solution will play better than a regular good psu if you dont use new high current batteries. It will just be decent since the esr of a single row of used batteries will be high. The risk is going up by a lot with older cells! If one fails down to 1-2V you will overcharge that cell and all that energy will heat up that failed cell. In all professional eboards there is a temp fuses to keep cells from blowing up. And battery packs in eboards fails quite often. A bms is a cheap solution and needed because of the relative high charge rate you plan to use.
Impishbynature, a good 18650 battery has the same ability as a huge capacitance and very low esr vs supercapasitor. I tried to build a booster psu for an rc car once. I learned that 4.2V stepped up to 11.1v and a lot of capacitance wasn't in the same league as a tiny lipo battery for buffering the 11.1V before going into the speedcontroller. Supercaps must be 10x better to compare to a lipo of similiar weight. Thats why no one uses supercaps in cars..
I could not find any info that supports this claim. Can you point me to some?
How about car audio or stereophiles who use batteries to get a better sound as they are the cleanest power source?
Both used lead acid for years and I don't know of any reason litium ion and other modern chemistries would not work.
The lipo's used in RC cars can and drones discharge at 50C: A 250 gram 4 cell 14.4V 5ah pack can discharge at 50x5= 250A or >3kW continues and about double as burst/peak.
There are even powertools battery powered as they can be more powerful then corded.
I didn't hear a difference with my 3251/5's on ebike batteries vs smps at low levels. I have not compared them at max volume (yet) as I have neighbors.
High power car stereo is not powered by the batteries, but capacitors that are charged by the lead acid cells. This capacitor energy is then chopped to a high frequency, transformed by an SMPS and stored into capacitors that finally run the amps. Basics. Nothing complicated. Anyone knows that. You can exchange the batteries by a sufficient 14.4 Volt power supply and will measure or notice no difference. If you exceed some power level, you will place a second battery near the amps, which will improve the energy flow to the capacitors. By installing them in parallel, you reduce the problem of the batteries not responding fast enough to the amplifiers power demands.
If you really want, you find such explanation in the net, but it seems your are somehow obsessed with your "Battery Idea".
Same is with high end home audio: Batteries do not improve anything. Has been done, tested, showed no advantage, forgotten.
In the end you run the amp on capacitors, that are continuously charged by batteries instead of a transformer. So simple. Many "Akku" pre amps run even on stabilized power supplies, driven by capacitors, charged by batteries. You should see that this is not really battery powered, as the amp stages only see the capacitors after the regulator.
Many high end builders see the power supply as an important factor for perfect sound. They have developed stabilized supplies that produce less noise than batteries. You can even make the noise discharging batteries produce, audible. You simply amplify the AC voltages which top the DC of supply under load. This noise is from the chemical process. Look for “super shunt supply” or the like. Lots of information in the net.
I´m perfectly sure you can find a hand full sellers/ builders of audio products, that will happily build such a battery power version of their amps for you. If the customer thinks batteries sound better, why not sell them, high end priced? Just as they would build a version with solid golden handles, if you pay the premium. Do you expect better sound from golden handles?
PS running an amp on 3 power lines instead of one phase has a huge advantage, as you reduce current peaks. If you want the perfect supply. You need 3 transformers and 3 rectifiers. The resulting voltage is much more DC than a rectified single AC source, as any phase is 120° apart.
In 110/120 volt countries you often find high power amps that run on two phases. This is because a single line would not give enough power.
If you really want, you find such explanation in the net, but it seems your are somehow obsessed with your "Battery Idea".
Same is with high end home audio: Batteries do not improve anything. Has been done, tested, showed no advantage, forgotten.
In the end you run the amp on capacitors, that are continuously charged by batteries instead of a transformer. So simple. Many "Akku" pre amps run even on stabilized power supplies, driven by capacitors, charged by batteries. You should see that this is not really battery powered, as the amp stages only see the capacitors after the regulator.
Many high end builders see the power supply as an important factor for perfect sound. They have developed stabilized supplies that produce less noise than batteries. You can even make the noise discharging batteries produce, audible. You simply amplify the AC voltages which top the DC of supply under load. This noise is from the chemical process. Look for “super shunt supply” or the like. Lots of information in the net.
I´m perfectly sure you can find a hand full sellers/ builders of audio products, that will happily build such a battery power version of their amps for you. If the customer thinks batteries sound better, why not sell them, high end priced? Just as they would build a version with solid golden handles, if you pay the premium. Do you expect better sound from golden handles?
PS running an amp on 3 power lines instead of one phase has a huge advantage, as you reduce current peaks. If you want the perfect supply. You need 3 transformers and 3 rectifiers. The resulting voltage is much more DC than a rectified single AC source, as any phase is 120° apart.
In 110/120 volt countries you often find high power amps that run on two phases. This is because a single line would not give enough power.
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These batteries need balancing, or a good fire insurance for your house. I strongly tend to recommend the balancing circuit over the fire insurance.
Other than that, I think this is a good idea. If you design the Power supply to have 2 operating modes (1. voltage mode once defined charge level is reached, maybe add a small "droop",2. constant current charging mode. It must charge maximum constant current unless the battery voltage is at the desired level. It must be designed for sustained current limit operation. The power level for the charger can be relaxed in comparison to only having the PSU supply the amp and no batteries. But not to 1 / 10th power, best is a compromise, maybe 1 / 3 or 1 / 2 maximum power level. This way, the PSU and the batteries would work together to keep up rail voltage during temporary high peak power demand.
Other than that, I think this is a good idea. If you design the Power supply to have 2 operating modes (1. voltage mode once defined charge level is reached, maybe add a small "droop",2. constant current charging mode. It must charge maximum constant current unless the battery voltage is at the desired level. It must be designed for sustained current limit operation. The power level for the charger can be relaxed in comparison to only having the PSU supply the amp and no batteries. But not to 1 / 10th power, best is a compromise, maybe 1 / 3 or 1 / 2 maximum power level. This way, the PSU and the batteries would work together to keep up rail voltage during temporary high peak power demand.