Powering soundbar with Li Ion

[ShadeTreeAudio]

I have a soundbar that I'm going to put into a smaller form box. I move it around my apartment a lot and just have the wireless subwoofer in a centralized spot. The long box has unnecessary space and it'd be easier to put on any of my shelves if it was smaller.

I have noticed the soundbar takes a 25v dc input. Why not also power it by battery? I have made a crude image of how I think this would be done. Any input is appreciated.

 

[neptronix]

Why not have a dedicated battery of the approximately right voltage?
8S lifepo4 would work pretty well if you cut off the top of the charge. Nominal voltage is 26v - close enough!

BMS optional if you're willing to occasionally balance the pack with w RC Charger that has balancing function.

 

[ShadeTreeAudio]

Why not have a dedicated battery of the approximately right voltage?
8S lifepo4 would work pretty well if you cut off the top of the charge. Nominal voltage is 26v - close enough!

I thought about it but I have some samsung 18650 cells I bought for a light and never used. In regards to voltage, 28.5 is probably high but it'd probably work while burning out slightly quicker. Either way I felt like maybe voltage regulation would be good since this has both bluetooth and wireless for the subwoofer. I feel like the amp won't care much about voltage drops but those might suffer from range issues.

Maybe I'm wrong though.

 

[neptronix]

Eh, your way is more complex and you take a 10-20% power hit for each DC-DC

I just recommend lifepo4 because it'd be good for a fairly steady voltage application:

 

[ShadeTreeAudio]

Eh, your way is more complex and you take a 10-20% power hit for each DC-DC

You're probably right, but I do love complexity. Realistically, it doesn't need long life either. It sits in my bedroom on a dresser 90% of the time. I just like to have it in the kitchen when I cook. It's too quiet from the other room.

My original idea was to use a 24v ebike charger direct to the bms, and the output from the bms to the soundbar. I'd have ac/dc losses but my electricity is included with rent.

 

[neptronix]

oh, even simpler.. extension cord or bluetooth headphones, lol

 

[ShadeTreeAudio]

oh, even simpler.. extension cord or bluetooth headphones, lol

You've got it wrong. Free electricity is MORE reason to pointlessly add batteries to things.

If I go back to the light idea, I'd have 36v battery to a 36v light. Work lights are a lot more useful without pesky cords on them. The problem is trying to fit the batteries in the current case.

 

[neptronix]

Yeah, but it's going to cost you money to waste that electricity.. i really don't understand the point

 

[amberwolf]

the vizio soundbar on my trike is made to run off a little dc wallwart, so i just made a plug to go straight to my lighting pack instead, since that's within the voltage range of the soundbar. works fine, and the lighting battery has more than enough spare capacity to run it and all the lights, so i don't need a separate battery for it, or a converter for the traction battery to power it.

so you could certainly build a pack for yours. it is highly likely that it will operate normally at a lower voltage than the power adapter lists, but i would shy away from running it above that limit. so you don't really need a dc-dc between battery and speaker, as long as your battery is never above the 25v wallwart output voltage the speaker expects.

(you may be able to run it above that, but you'd want to investigate the power input stage before trying, to be sure all the components on the input bus can handle higher voltages; some are not well-engineered for anything above the original adapter).


if you're going to use a dc-dc, then you might as well use a much lower voltage battery of whatever type will fit in teh case you want to use, and then convert it up to the speaker input voltage.



this has a few more details on the trike soundbar

RadRunner Plus Rebuild

About a year ago my very customized RadRunner Plus was stolen. I've had a few projects under the belt since then, and even some high power bought two wheelers (Luna XXX) but nothing felt quite right. So when I saw a guy selling a RR+ with the OC Cafe Racer seat already included, I jumped on it...

endless-sphere.com

 

[rafalg]

Many DC-powered devices have a built-in voltage regulator so sometimes it's possible to skip one step-up or step-down converter between the device and a battery. But this requires some investigation and/or testing.
Why this suggestion - because if you build a 24V battery (like 6S Li-ion) and connect it directly to the subwoofer, it might work also as the battery discharges to, say, 18V - so you'd save one DC conversion.
Might also be true with higher voltages, but I don't recommend guessing or assuming anything here.
Some time ago I had to power one 12V IP camera and discovered it runs just fine as low as 8.5V (just takes more current - this was the indication that there's a voltage regulator inside). So then I went the other way and increased the voltage a bit - and it also ran OK also on 15V input (maybe it could go even higher, but i didn't want to find the limit).

With audio, i think, the digital electronics run on 5 or 3.3V, and 25V is needed for the amplifier. So there's a chance it might work on wider voltage range, just the sound power would vary. For example some audio amplifier chips might work with range like 5-25V or 10-30V (of course with lower volts you get less audio power).

 

[ShadeTreeAudio]

the vizio soundbar on my trike is made to run off a little dc wallwart, so i just made a plug to go straight to my lighting pack instead, since that's within the voltage range of the soundbar. works fine, and the lighting battery has more than enough spare capacity to run it and all the lights, so i don't need a separate battery for it, or a converter for the traction battery to power it.

so you could certainly build a pack for yours. it is highly likely that it will operate normally at a lower voltage than the power adapter lists, but i would shy away from running it above that limit. so you don't really need a dc-dc between battery and speaker, as long as your battery is never above the 25v wallwart output voltage the speaker expects.

(you may be able to run it above that, but you'd want to investigate the power input stage before trying, to be sure all the components on the input bus can handle higher voltages; some are not well-engineered for anything above the original adapter).


if you're going to use a dc-dc, then you might as well use a much lower voltage battery of whatever type will fit in teh case you want to use, and then convert it up to the speaker input voltage.



this has a few more details on the trike soundbar

RadRunner Plus Rebuild

About a year ago my very customized RadRunner Plus was stolen. I've had a few projects under the belt since then, and even some high power bought two wheelers (Luna XXX) but nothing felt quite right. So when I saw a guy selling a RR+ with the OC Cafe Racer seat already included, I jumped on it...

endless-sphere.com

I'm actually trying to see if I can find a

the vizio soundbar on my trike is made to run off a little dc wallwart, so i just made a plug to go straight to my lighting pack instead, since that's within the voltage range of the soundbar. works fine, and the lighting battery has more than enough spare capacity to run it and all the lights, so i don't need a separate battery for it, or a converter for the traction battery to power it.

so you could certainly build a pack for yours. it is highly likely that it will operate normally at a lower voltage than the power adapter lists, but i would shy away from running it above that limit. so you don't really need a dc-dc between battery and speaker, as long as your battery is never above the 25v wallwart output voltage the speaker expects.

(you may be able to run it above that, but you'd want to investigate the power input stage before trying, to be sure all the components on the input bus can handle higher voltages; some are not well-engineered for anything above the original adapter).


if you're going to use a dc-dc, then you might as well use a much lower voltage battery of whatever type will fit in teh case you want to use, and then convert it up to the speaker input voltage.



this has a few more details on the trike soundbar

RadRunner Plus Rebuild

About a year ago my very customized RadRunner Plus was stolen. I've had a few projects under the belt since then, and even some high power bought two wheelers (Luna XXX) but nothing felt quite right. So when I saw a guy selling a RR+ with the OC Cafe Racer seat already included, I jumped on it...

endless-sphere.com

16v for a 24v? Over volting a stereo is not an issue. I think 28.5 is probably excessive, but most devices will work within 5-10% up or down. Why would I undervolt an already low power system?

 

[ShadeTreeAudio]

Would this be a better solution.

6s 22v with 25.2 charging

I actually busted out a multimeter and the wall adapter reads 25.63 volts.

 

[rafalg]

25.2V is needed for li-ion, the power adapter is 25.63V - looks close enough to me to use it as a charger for the li-ion pack, but im not an orthodox regarding the electronics and others might disagree.
But the power supply is 2A rated so there's no risk of too much charging current, and a tiny bit higher voltage would translate to 4.26V per cell in 6S arrangement instead of 4.20, which would be handled by the balancer in the battery without a problem (i mean this is tiny overcharge which also can happen if you have a dedicated 25.2 li-ion charger so nothing to worry about IMHO).

 

[Chalo]

I have a soundbar that I'm going to put into a smaller form box. I move it around my apartment a lot and just have the wireless subwoofer in a centralized spot. The long box has unnecessary space and it'd be easier to put on any of my shelves if it was smaller.

The internal volume of a speaker enclosure is an essential component of its sound quality, frequency response, and performance. If you must reduce its physical size, you may need to add a tuned port (or change the dimensions of the existing tuned port) to keep it sounding good.

In my limited experience, digital amps usually have a pretty wide range of operating voltage (like a 2:1 range or so), so you really only need to be concerned about the limits of the components. Lower than stock voltage might be just as good as higher.

 

[ShadeTreeAudio]

The internal volume of a speaker enclosure is an essential component of its sound quality, frequency response, and performance. If you must reduce its physical size, you may need to add a tuned port (or change the dimensions of the existing tuned port) to keep it sounding good.

In my limited experience, digital amps usually have a pretty wide range of operating voltage (like a 2:1 range or so), so you really only need to be concerned about the limits of the components. Lower than stock voltage might be just as good as higher.

Kind of a pointless comment when the speakers are inside enclosures inside the soundness case. If be putting those enclosures into another one. The size of what i put them into is irrelevant.

I've actually built boxes for speakers before. I'm shade tree audio. I came here for electronics help which I'm not getting, so I'm just gonna use these speakers and a Dayton or tpa board of some sort because i know how to make that work properly. I'll probably pull the amp off the subwoofer

 

[ShadeTreeAudio]

The internal volume of a speaker enclosure is an essential component of its sound quality, frequency response, and performance. If you must reduce its physical size, you may need to add a tuned port (or change the dimensions of the existing tuned port) to keep it sounding good.

In my limited experience, digital amps usually have a pretty wide range of operating voltage (like a 2:1 range or so), so you really only need to be concerned about the limits of the components. Lower than stock voltage might be just as good as higher.

I'm finally home. Here's the speakers you want me to put in a new box. Lemme know the dimensions i need. View attachment 1000000303.jpg

 

[rafalg]

Regarding the electronics advice, i think you got it here (at least one possible approach).