It's very common for devices such as yours to have a noisy inverter. They're really not made for audio.
Battery-Powered Audio System Buzzing?
I’ve seen many people proclaim the merits of powering one’s audio system with a battery, rather than from the wall AC power. I purchased an Anker SOLIX BP1000 battery as a household backup in case of power outages. I figured why not give it a shot on the audio system.
Well, it powers the system just fine, however, there is a buzzing that comes through the speakers when using the battery as the power source. When plugged directly into the wall (or rather through a Zero Surge unit), there is no buzz. It is silent as can be.
Does anyone have any ideas as to why the buzz might be happening when powered by the battery? Any insights would be much appreciated! For reference, I am running a Macbook -> Schiit Yggdrasil OG ->Don Sachs preamp -> Schiit Tyr monoblocks -> Tekton Encore towers.
To follow on the already correct advice from @cleeds , it's a lot cheaper to provide a square wave output UPS than a sine wave. Unless it specifically says "sine wave output" it probably is not. The square waves produce a lot of higher frequency harmonics (relative to 60 Hz) that make it through the power supplies. Also make sure you don't have your system grounded through some other means, like using 1 device which is not battery powered but some that are. It could do weird things in terms of the ground voltage. This includes coaxial and USB connections. |
Quality batteries with the correct match up can deliver clean power. In case your case, your system is putting too much demand on your small battery. No chance of delivering consistent clean power at any point. I have hooked up my Yeti Goal Zero 1500 with my Accuuphase and streamer with good results. Being a class a/b amp its putting very little demand on inverter. Drawing about 100 watts. With your system being demanding for power, even the Yeti 1500 will not get you there. Also, not all batteries inverters are equal. In my opinion, a battery to meet your clean power needs is cost prohibit. Cost benefit does not pencil out. |
Thanks to everyone for the input. I confirmed that my Anker battery creates a pure sine wave. It also has a maximum output of 1800 W, and my system on average draws about 175 W. @erik_squires thanks for the suggestion, I had not put everything in the system on the battery. Once I did the buzz basically went away. Thanks again! |
@sid-hoff-frenchman , do you hear an improvement when using the battery versus plugging into the wall?
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If you are going to use a battery in hopes of hearing the effect of quieter power, it makes sense to try to use the batteries power directly without interposing an inverter. What I mean is that a battery supplies direct current. The interior circuits of all hi-fi equipment Use direct current. Why bother changing to alternate current only to have to convert it back to direct current? The easiest way to do this is to use hi-fi components that employ an external DC power source (the infamous wall wart) generally, these will be less expensive but nonetheless high-quality sources, Dacs , and amps such as a raspberry pi based streamers, topping dacs, and Fosi amplifier just as one set of examples. You will need to find separate lithium ion batteries for each component that match. It’s voltage and amperage requirements, but this is not too hard to do and considerably less expensive than the large battery solutions already discussed. I have done this and have been very pleased with the results. |
@sid-hoff-frenchman said;
Did you try that on the 120Vac output on the inverter?
As I read the above quote, you were only using the battery/AC inverter to feed the audio system . Therein not using the wall outllet AC mains as well at the same time to feed other audio equipment. Therein two different power sources to feed audio equipment whose signal grounds are connected together by wire interconnects. Is that correct? If you were using both power sources, the chance of the two power sources AC sine-waves being in sync, in phase, with one another are slim to none. As for grounding of the inverter... Did you read the instruction manual. What does it say about earth grounding the inverter? My guess it says to connect it to the electrical grounding system of the building/house. If you were using both power systems, the inverter power and the wall AC mains power to feed equipment connected together by wire interconnects and the inverter was not grounded to the EGC, (equipment grounding conductor), at the same wall outlet I can see the inverter using the signal ground wire in the interconnect as a path to ground. That could possibly be the result of the buzzing you were hearing through the speakers. But, if only the inverter was being used as the power source, and it was earth grounded, if that is what the inverter manual says. Well then ??? . . |
@immatthewj I am trying this setup with both my upstairs and downstairs systems, the difference being the downstairs setup has the Schiit Aegir going into Tekton Impact monitors. For the downstairs setup, yes it is a dramatic improvement. The sounds was great to begin with, but on battery there is a wider soundstage, more holographic presentation and for lack of a more clinical term - an intoxicating musicality. On the upstairs system with the Tyrs and the Encore towers the difference is harder to tell. Now that I have it setup on battery I will try A-B ing between battery and wall-power to listen more critically for differences. While I appreciate the other suggestions, this experiment is already into as deep technical waters as I feel comfortable wading through. And yes, originally when I posted I still had 2 subs and the DAC going through wall power. Once I put everything on the battery the buzz disappeared. |
Glad I could help. :) As far as I remember these issues arise due to the generator neutral and the house neutral not being bonded to the same reference point setting up a neutral/ground differential which causes current flow through the ground... or something like that. At least this will point you in the right direction of explaining why. The solution besides putting everything on the battery would be to use transformer based isolators to anything not on the battery. |
Not really.... A standby generator is connected to the electrical service entrance neutral conductor. BUT, DO NOT TRY TO CONNECT THE HOT FROM THE GENERATOR DIRECTLY TO THE HOT OF THE UTILITY POWER. The Utility power system will win the battle. You can kiss the generator goodby and probably a lot of associated electrical equipment. It has nothing to do with the neutrals of the two power systems being bonded together. It has everything to do with the two AC power systems are not in sync with one one another, therein, in phase with each other.. . |
@sid-hoff-frenchman I'm not sure if I'm tracking. Are you testing or horsing around with the battery? Or will you be integrating with your system for mid-term or long-term use? If it's a mid- or long-term route, I would advise against taking that road. No matter what benefit or perceived benefit you are getting from using it, forgo it. There may be unknown or unseen risks that could emerge later, potentially damaging your audio gear. I'm sure the designers of battery manufacturers do not have home audio gear in mind. Based on my experiences and observations, even the most well-planned designs and tested products can still fail at some point. Nuclear power plants, aircraft, vehicles, motors, and batteries are good examples.
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@immatthewj After A/B-ing with the upstairs system (Schiit Tyrs/Tekton Encores) I've come to the conclusion that while there is a difference between battery and wall power, it is very slight. One is not better than the other. Not worth the annoyance of dealing with the batteries. I will A/B more extensively with the downstairs system (Schiit Aegir/Tekton Impacts) and report back. It was on that system that I originally noticed the big difference I described above. We'll see if that holds under more scrutiny. @goldenways I definitely don't want to harm my equipment. I'll reach out to the manufacturers of all my gear and see what they think about powering their stuff with batteries. |
Sounds like a good plan. My guess is the manufactures are not going to stake their reputation on batteries. They will stick with the tried and true way that is normally done. Even if they say go for it, most likely there will be a large asterisk to the statement. My asterisk to my opinion “I might be wrong” |
Sounds like a good plan. My guess is the manufactures are not going to stake their reputation on batteries. They will stick with the tried and true way that is normally done. Even if they say go for it, most likely there will be a large asterisk to the statement. My asterisk to my opinion. “I might be wrong” |
@goldenways Strictly, the OP is not using batteries to directly feed his equipment. He is using an inverter to convert the battery DC to mains-like AC. Almost certainly the inverter will contain a switched mode power supply, especially as it is a "pure sine-wave" inverter. I have a set up like this in my motorhome. Interestingly the 2000-Watt sine-wave inverter I use will synchronize to mains frequency within a couple of cycles if mains is connected. My lithium batteries are nominally 12-Volt but the actual voltage ranges anywhere from 14.7 if the sun is shining on my solar panels to about 11 just before the batteries shut themselves down. I hate to think how many switched mode power supplies are used inside my components to deliver the various voltages actually needed! |
I assume the inverter circuitry uses a static switch that does not connect, parallel, the inverter to the AC mains power until the inverter AC sine wave is in sync with the AC mains sine wave.
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