Apart from the logo on the top and the labeling around the bottom ring, no identifying marks to speak of. No label, no model number, no nothing - that was clue no.1 regarding its non-genuine-ness.
Clue no.2 - a microSD card slot. Now, i'm no expert in "consumer audio", but i'd be VERY surprised if Beats actually ever included such a(n arguably) useful feature in one of their products. I stand to be corrected though, of course, but i'm highly skeptical.
In addition to that, there's the power switch, and the mini-USB connector on one side. The latter is labeled as "DC5V/AUX/FMANT". The "DC5V" bit is quite self-explanatory (power and charging the internal battery); "FMANT", i assume, in a similar way to how phones use the headphone cable as an antenna. Not quite sure how the "AUX" comes into play, though - potentially via some custom cable, like a 3.5mm jack to mini-USB? Perhaps the internals might shed some light on this.
On the other side there's a little hole labeled "MIC", and a trio of buttons - play/pause, volume up and volume down. Not quite sure what the microphone's supposed to be doing, though. Unless this thing has some bonus "handsfree" type functionality?
I'll tell you what, though - it's got a reassuring amount of heft to it. Peeling back the pink silicone-rubber "condom" on the outside provides a swift explanation - the bulk of the enclosure is powder-coated steel.
Since there were no visible traces of assembly, i took a punt and peeled off the rubber sheet on the bottom. That revealed a reassuring trio of screws. Removing those and the bottom cover revealed part one of the "goodies" (as it were).
The "center of attention" is the castellated daughterboard containing an RDA5851SX processor. The first page of the datasheet lays it all bare - Bluetooth 2.1 + EDR, FM tuner, integrated Flash memory, battery charging, USB / SD / I2C / I2S controllers, as well as a stereo DAC plus a separate "voice DAC / ADC", so it may well have handsfree features too. Not quite sure how all this can be controlled from a three-button interface, but that may be facilitated by the Bluetooth connection.
The other larger chip is a Chipstar CS8571E dual-mode bridged mono amplifier. Aside from a couple transistors and diodes, the only other visible chip is a SOT23-5 footprint "B1NE". Couldn't quite identify it entirely, but i found two possibilities - either an XC6115 voltage detector, or a 24__01 serial EEPROM chip.
Respecting the first commandment of (electronics) troubleshooting, ie. "Thou shalt measure voltages", sure enough, the battery was totally dead. Speaking of which, flipping the board revealed that too.
The capacity of the cell wasn't clearly marked on it, but a quick lookup of its size-code (552927 = 5.5mm thick, 29mm long and 27mm wide) led to an outdated AliExpress page with a list of cell sizes, this one being indicated as 260mAh.
And whaddya know - fully protected, to boot. Borderline-impressive, in a cheapo device. But then again, with the main body made out of a chunk of steel, this might not be quite the most cut-rate of jobs, on second thought. The tiny PCB at the end of the cell contains the now-"classic" DW01 supervisor chip, and an 8205S dual MOSFET. But as expected, the cell's well depleted, clocking in at a mere 1.02V or so.
The other side of the PCB doesn't contain much - the card slot, buttons, three LEDs, the USB connector and the power switch. On the other hand, we have a ballpark date for the thing - late 2013 (at least as far as the board design is concerned).
But waaaaaait a minute - what's that hiding inside the bowels of this thing? It's a passive radiator, of all things! Hey, someone might've actually spent some time putting some effort into designing this thing - someone with some knowledge in the field of acoustic enclosures. That also explains the perforated "vent" on the bottom of the casing. On a related note, the driver itself seems to be some 2"(-ish) jobbie.
That about covers the teardown part of this - not much point in destroying the thing, just to see the back of the little speaker.
Plugging in a mini-USB cable made the red LED light up instantly, and the voltage between the "BAT+" pad and ground jumped from zero to 2.887V and slowly rising. I'll let it take its time and charge up the cell. Once that's done, i'm seriously considering swapping out the connector for a micro-USB one, out of sheer practicality.
Sure enough, after about an hour, i flicked the switch, and it powered right up. Granted, the quick, brief flash of the two blue LEDs startled me, but a couple seconds later, a male voice with a strong Asian accent said "Bluetooth model has been open". Yes, "model". Because reasons.
And i figured out the "interface" as well - holding down the play/pause button scrolls through the modes (Bluetooth, radio, aux in, and "TF" ie. reading MP3s off the microSD). Radio mode is just noise, couldn't even figure out how to turn it down (because it's all noise, and it's friggin' LOUD), and i'm not sure it even works without an actual antenna. That being said, the middle of the five mini-USB pins (which would normally be one of the two data lines) does have a thicker trace ending in a via underneith the little daughterboard, so my earlier hunch might've been correct. In MP3 playback mode, +/- skip tracks forward and back, and holding them down actually works the volume.
Right then - now to desolder the wires and see about swapping the USB connector...
Ehrm... Nevermind - due to some traces to and from the power switch, that run right underneith the mini-USB connector, swapping it for a micro one is a no-go. Yes, running short wires from the pins to the pads wouldn't have been an issue, but there's no ground-plane to solder the "back" corners of the micro-USB socket to, so long-term mechanical durability goes down the drain. Ah well...
Before reassembly, i took the time to twist together the pair of wires coming from the speaker, and plugged up the hole they poke out of, with some RTV silicone. I had noticed air puffing through that during music playback, and that partially defeats the workings of the passive radiator ("stealing" some of the already limited bass potential). That, plus a strip of double-sided tape, to tack the battery onto the circuit board, so it doesn't rattle around inside.
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