Will this amp work with an external power bank?

[SNIRAVIV]

hey.
i'm building a small portable speaker and thinking of using an external battery something like a power bank. is it posible? and if so will i be abel to get reasonable power from that setup?:

Up2Stream 2.1 Plate Amplifier​

Tang Band W3-1876S Subwoofer 4 ohms 15WRMS​

Dayton Audio HARB252-8 8 ohms 10WRMS X 2​

https://www.soundimports.eu/en/tang...zYxNS4xLjAuMTcyNDg3NzYxNS4wLjAuMTI3NjE0NzU3Mw..

https://www.soundimports.eu/en/dayt...zYxNS4xLjAuMTcyNDg3NzYxNS4wLjAuMTI3NjE0NzU3Mw..

https://www.soundimports.eu/en/aryl...zYxNS4xLjAuMTcyNDg3NzYxNS4wLjAuMTI3NjE0NzU3Mw..

 

[Ixnay]

There are concerns/questions here. I am assuming that you want to apply DC power where normally a power supply would go. In short it all comes down to the current draw from the circuit being fed. I owned a little 15 watt amp that had its own internal battery and was impressed by its performance and not needing to be charged all the time. I think that it was a Red Wine amp. In that case, care was taken by the designer to marry a battery supply with the amp.

 

[SNIRAVIV]

"you want to apply DC power where normally a power supply would go"
yes

 

[ICG]

External battery: Yes.

Power bank: No. Its minimum voltage is 12V (max 24V). Even with a buck converter it's not working. Get Li-ion battery packs or use battery drill batteries. Go for 14-24V, the voltage drops too fast on 12V batteries, you can't use much of the charge.

 

[chris661]

USB-C-PD batteries can put out 5-20V. Might be worth looking into.

Chris

 

[ICG]

USB-C-PD batteries can put out 5-20V. Might be worth looking into.

They can do that if the connected USB device tells the PB it can take the voltage. The amp isn't even a USB device, let alone able telling what voltages it's taking.

E: It is a USB device, sry. But not USB 3.

 

[chris661]

True, but cables like this exist: https://thepihut.com/products/15v-5a-usb-c-3-1-pd-to-5-5mm-barrel-jack-cable-1-2m-with-e-mark
There's also a 20v option: https://thepihut.com/products/20v-5a-usb-c-3-1-pd-to-5-5mm-barrel-jack-cable-1-2m-with-e-mark

Chris

 

[ICG]

Ah, I didn't know that something like that existed. Thanks!

 

[SNIRAVIV]

OK, i'm a little confused now. can someone show an example of what battery i need to buy? using the "20V 5A USB-C 3.1 PD to 5.5mm Barrel Jack Cable"

 

[SNIRAVIV]

is somthing like that OK? or the 12V 2A output not enoght?

 

[chris661]

What the USB-C-PD adapter cables do is simply ask the USB battery to supply a specific voltage, and then the cable passes it through. There's no DC-DC conversion going on in the cable itself.

So, if you want 20V output, you need a battery capable of 20V output. If you want 5A@20V, you'll need a battery capable of supplying 100w. I have one of these: https://www.anker.com/uk/products/a1289?variant=42498009497764
It'd manage the 100w for your amplifier, and have another USB-C output for charging a device, running DSP, etc. Not cheap, though.


Chris