Pure Sine Wave Battery Backup Pack for Preamp

I purchased this Aeiusny solar battery pack last year. It was a great deal and I had my eye on pure sine wave inverter for some times due to PG&E power shut down in 2019 so I pulled the trigger when I saw it is 500W with pure sine wave without much thinking.

I was wondering how should I check it’s capability for the battery usage then suddenly I figured why not try it with my audio system to see how long it will work since it claims it can provide clean power for the sensitive CPAP devices.

Wow, what a surprise when I plug my Bel Canto DAC3 alone to Aeiusny and use its battery with the pure sine wave AC output. My audio system sounds better with more clarity comparing to the DAC3 was directly plugged on the wall. I did try to switch back and forth between wall outlet and Aeiusny to compare my finding. It is quite clear Aeiusny using the battery does give the better sound which I did not expect. Now switching the AC power is not a blind ABX test as you have to power down the DAC3 to switch the power cord. You might think this is a placebo effect or psychoacoustic effect as some people believes. But the bottom line is that Aeiusny is not causing any negative sonic impact as some people reported in audiophile forums for other pure sine wave inverters. This alone gives Aeiusny a big plus as a product especially for the audiophile with limited budget. I am a EE guy so I normally do not believe power cable can affect the sound quality if your equipments are designed properly. I also did not believe power supply conditioner will help audio system as each component shall have solid internal power unit to get the clean DC levels for audio purpose. Having said that, I am an audiophile so I do believe if there is power supply current bottleneck or some major power noise or power fluctuation then it will affect the sonic performance. I did have experience when my power amp was plugged in a power strip with surge protector and causing sound quality issue. Connected my 200W power amp to the wall directly fixed that problem so I think that surge protector might be choking the power amp when it needs the dynamic surge current. As we know the source of the music is the most important one, this is why I was using Bel Canto DAC3 for this experiment as minor change on it could be amplified for the sound quality impact. After this initial wow, I did try to plug my preamp and Oppo 105D Blu-ray Player (used as a streamer for my DAC3) to Aeiusny too to see if there is more sound quality improvement. I do not have enough wall power outlets for my AV system so my preamp is normally powered from the power strip as it consumes relative less power so it was working fine. Further experiment on this shows no sonic improvement by adding my preamp and Oppo 105D to Aeiusny. Not a surprise to me (my Oppo was connected directly to the wall) as surge protector shall not affect them as I believed.

Since Aeiusny can be used as UPS so I did connect its AC input to the wall and listened my music with DAC3 alone powered through Aeiusny AC output. I can plug and unplug Aeiusny AC input power cord in this way and I did hear the difference. With Aeiusny AC input powered, it sounds same as DAC3 is powered directly from the wall. With Aeiusny AC power input unplugged, I felt there is more clarity on the sound quality especially for the acoustic guitar and piano in the music. As we audiophile knows that daytime sound quality is not as good as the late night sound quality when we enjoy the music, part of the suspicion is the power grid noise is going through our audio equipments that cannot be filtered out and affecting the music sound quality. If this Aeiusny is indeed helping as I am hearing then we can guess its pure sine wave quality shall be quite good. It will be great if someone can measure this to confirm it.

Ok, now let’s talk about Aeiusny battery backup capability which is the main function of this unit. My DAC3 by its spec shall consume 15W in its standby mode. It has a class A amplifier along with the DAC to decode the digital music signal so I assume it consumes 15~20W during normal operation. First night I was listening my music for 2.5 hours with DAC3 alone and Aeiusny display showing the battery capacity dropped to 92.5% which is amazing and did not make sense to me.

I charged Aeiusny overnight and next day I plugged my DAC3, preamp, and Oppo to Aeiusny (very nice that it has 3 AC receptacles) to play music for 72min and this time it dropped the battery capacity from 100% to 70%. My Oppo 105D spec shows active power consumption as 55W and standby as 0.5W. My preamp spec does not show its power consumption but I checked with similar machine it shall be around 21W. Then I removed my Oppo from Aeiusny and play music for another 72min using the same flac music file. This time the battery capacity display dropped from 70% to 42% (used 28% battery, wow) and this is much more than I would expect. I guess the display may not be very linear for the battery capacity or somehow my preamp is consuming much higher power than 21W (not likely though).

I charged Aeiusny overnight again then use DAC3 alone for 72min, it only dropped the battery from 100% to 99% this time. This seems indicating Aeiusny is charging the battery to 105~110% when it is fully charged overnight. This can also explain why my first night only used 7.5% with my DAC3 alone for 2.5 hours. According to the web info, this is a typical practice for the device used to optimize its battery capacity. If you want to maximize your battery lifespan it might be wise to charge Aeiusny to 75% and use its 50% capacity (down to 25%) for each using cycle so you might be able to double or even triple Aeiusny battery lifespan. Only if you plan to use its full capacity such as a camping trip you would charge it overnight to maximize the length of your power supply.

Now I have been using Aeiusny backup battery to power my DAC3 for many times, the average battery capacity used by DAC3 alone with 72min music listening is about 7% so here is the calculation we have:

288Wh * 7% * (60min / 72min) = 16.8W which is assuming 100% efficiency, with 85% efficiency as guided in Q&A of this product, my DAC3 would have consumed 14.28W which is lower than its standby power spec level. I guess the truth is in between these depending on the load characteristic that Aeiusny is powering for.

Based on these experience, it seems Aeiusny does have good efficiency as the battery capacity vs my equipment power consumption. But I did find the display seems dropping faster at its lower percentage level so it may not be very linear as the battery capacity indicator. I also found if I am not charging the battery overnight the battery will decline a few percentage next day when I power it up (I did turn its AC power switch off). It is interesting when you plug and unplug its AC input power the battery capacity display will go up and down for awhile before settling down which might be doing some kind of calibration. Plugging or unplugging the load on its AC output will also affect the display for battery capacity display so it may not be very reliable but it does give you some idea how much you are using.

Overall, I am pleasantly surprised how well it works and how much it can improve the sound quality on the Bel Canto DAC3 which is already a very good DAC. FYI, DAC3 has transformers on its input and output ports so this might be another factor it works well with this pure sine wave battery power inverter. The only issue is that I cannot power my DAC3 overnight to keep it warm since I do not want to charge Aeiusny overnight all the time to shorten its battery lifespan. It is a great way to isolate your sensitive equipment from the noisy power grid if your wall power is affected by inside or outside noisy environment of your house. The fan on Aeiusny only turns on a few second when I turn on its AC power. It is dead quiet most of time so it does not affect my music listening. The only time the fan was on again is when I was charging Aeiusny and the box was little warm. Most of the time it is very cool so no fan kicked in at all. My audio system is also dead quiet as usual so there is no negative impact from Aeiusny as a battery power supply, amazing!