DROK LM3886TF 60W 20~28V amplifier on Amazon Prime

[CZ Eddie]

Anyone familiar with this amp?
I'm looking for something small like this, that does not have volume knobs or anything else sticking out of it (space constraints in enclosure).

Amazon.com: DROK HI-FI Digital Stereo Power Amp Circuit LM3886TF Small Audio Amplifier IC Mono 60W AC 20~28V: Electronics

Product Model:LM3886TF

• Operating Voltage:AC 20V~28V
• Output Power: 60W
• Resistance:1% copper foot metal film
• Can monolithic or used in parallel

Basically, I'm wondering what type of power I'll get with my application?
I've got a single 4 ohm, power hungry speaker.
And I think my battery setup will be ~12 volts?

Then I've got the following battery/case/charger setup:

3 each 18650 batteries
http://www.amazon.com/18650-Recharg...&redirect=true&ref_=oh_aui_detailpage_o01_s00



battery case for three 18650 batteries wired in series.
http://www.amazon.com/uxcell-Batter...&redirect=true&ref_=oh_aui_detailpage_o00_s00



And this is the charger I got to charge the batteries with.
The speaker will rarely ever be connected to the charger while playing audio.
Amazon.com: 90W AC Power Adapter/Battery Charger for Toshiba Satellite A135-S7406 A205 A205-S5000 A305 A305-S6916 A505 A505-S6980 L305D L305D-S5934 L40-139 L455D-S5976 M305D-S4830 P205-S6267 U405D-S2850: Computers & Accessories

 

[abraxalito]

You need a balanced supply for this, so 3 18650 won't cut it, it should be 6.

 

[CZ Eddie]

Whoah. Okay, thanks.
Crud.
Okay, just bought a couple of these 18650 protection boards then.
Two boards for six batteries:
10A bms Charger Protection Board for Pack of 3 18650 Li ion Lithium Battery Cell | eBay

 

[CZ Eddie]

Any suggestions on a heatsink to add to it?
I'm guessing that's the only other thing I'll need, aside from the Bluetooth board which I already have.

 

[abraxalito]

You'll want something the full width of the PCB and the height should be say 75mm with a depth of at least 30mm. Choose a black anodized one over plain shiny aluminium.

As regards to power output, with 6 cells into 4ohms, you'll have about 8WRMS.

 

[CZ Eddie]

8 Watts?
So is the 60 watt rating just specs BS or is this a limitation of the battery pack?

I need about 33 watts minimum for my single channel portable speaker and it's got to run on battery. Any suggestions?

I appreciate the help. I'm way out of my knowledge level when it comes to this battery pack stuff.

 

[CZ Eddie]

I ended up buying this board instead.
It's been talked a lot about on this forum so I'll start researching all the threads this evening.

DC 12V-24V TPA3118 BTL 60W Mono Digital Audio Power Amplifier Board Module M374
DC 12V-24V TPA3118 BTL 60W Mono Digital Audio Power Amplifier Board Module M374

 

[abraxalito]

Yes, you're limited by your relatively low voltage battery pack. 60W is achievable but you'd need something like 70V total supply as well as a bigger heatsink. I was going to suggest classD but I see you've already discovered that

Note that with this new board and the same 6 cells you'll get round about your target power. However 6 freshly charged 18650s will exceed the maximum voltage rating so I'd suggest reducing the number to 5.http://www.diyaudio.com//www.pinterest.com/pin/create/extension/

 

[CZ Eddie]

Note that with this new board and the same 6 cells you'll get round about your target power.

YESSS... thank you

 

[CZ Eddie]

OMG, I'm such a dumbass.
I already have a board that I bought a couple weeks ago and forgot about. lol
http://store3.sure-electronics.com/aa-ja32171-1514

 

[xrk971]

Glad you saw the light with class D and portable battery powers application. The class AB chip amp would have chewed through batteries like nothing. LM3886 is almost a heater from my experience with them.

The Sanwu 3118 PBTL monoblocks are the BEST stock class D amps you can get for up to 60w operation but run them below 40w to keep sound clean.