Sourcing Bluetooth speakers

Drivers. Diameter, type, how many, and how they are arranged. A larger driver moves more air; two small drivers are not one large one. Ask for the driver's own specification sheet, not the speaker's.

Enclosure. Internal volume, wall material and thickness, bracing, and how the driver is sealed to the baffle. A speaker is a pressure vessel at low frequencies, and a flexing or leaking box is the single most common reason a product sounds thin next to a competitor with the same driver.

Passive radiator or port. Which one, its tuning, and its excursion limit. This is what produces perceived bass in a small enclosure, and it is also what rattles first when it is under-specified.

Amplifier. Continuous output into the actual driver impedance, and what happens at the limit — whether it clips, limits gracefully, or shuts down. Ask for the amplifier part and its continuous rating rather than a marketing figure.

Measured output. A sound-pressure level at a stated distance with a stated signal, measured by the factory and repeatable by you. If the supplier cannot produce that, the wattage they are offering instead is not a substitute for it.

Bluetooth qualification. Selling a product that uses Bluetooth technology requires membership of the standards body and a qualified design with a Declaration ID listed against a member company, and the word marks and logos are trademarks. If you are branding a factory design, establish whose qualification you are relying on and whether your version needs its own.

Radio approval per destination market, which is separate from the qualification above. The EU and UK expect a technical file and marking; the United States has its own equipment authorisation; Japan and Korea have their own national approvals. One does not substitute for another.

Battery. Portable speakers carry lithium cells, sometimes large ones, so transport documentation applies and the cell specification matters for the same reasons it does in a power bank: name the cell manufacturer, require new rather than reclaimed cells, and ask for the cell's own test report. Transport thresholds are deliberately not published here — the guides on watt-hour conversion and shipping lithium batteries by air carry them.

Water and dust ratings. An IP rating is the outcome of a defined test on a defined unit, not a property the product owns. Ask which test, on which model, by whom, and read the report — and note that a rating measured before a housing seal was value-engineered describes a product you are not buying.

And check the marking requirements for your market. The rating, the model, the manufacturer or brand identification and the required symbols have to be on the product durably. A silk-screen that washes off a "waterproof" speaker is a compliance problem with a photograph attached.

Compare in one room, at one time, at matched loudness. Two speakers auditioned a week apart cannot be compared, and the louder of two always sounds better until the levels are matched. Match by ear at a moderate level first, then push both.

Push them to the limit deliberately. Bass-heavy material at high volume is where the enclosure, the passive radiator and the amplifier limiter reveal themselves. A speaker that buzzes, rattles or compresses badly at volume will be returned; a specification sheet will never tell you that.

Test the connection the way it is used. Pairing speed, reconnection after being switched off, range through a wall, and whether it drops when a microwave is running. Also test whatever multi-speaker pairing mode is claimed, with two units, because that feature fails more often than it works.

Test outdoors and at temperature. Portable speakers live on beaches, in showers and in cars. Leave one in a hot car and one in a fridge and then run them.

Then take one apart: enclosure wall thickness, sealing gasket, bracing, driver mounting, the amplifier board and the battery marking. That is where the price gap between two visually identical speakers becomes visible.

Business licence and business scope (经营范围) first — a manufacturer's registered scope names production, a reseller's names only sales, wholesale or trade. Audio has an unusually deep layer of assemblers, so this check does more work here than in most categories.

Ask who does the acoustic design and the tuning. A factory that can explain why the port is that length and what the passive radiator is tuned to is a different counterparty from one that assembles a reference design and cannot change it.

Ask what is tested on the line. Every-unit audio testing (a frequency sweep with a pass/fail window) is common in good factories and absent in others, and it is the test that catches a mis-assembled driver or a leaking seal before it ships.

Then buy three, test two hard and keep one sealed and dated. And if the enclosure is your own design, agree in writing who owns the tooling before the money moves.

Every supplier on this site is a manufacturer, and the registered-scope check is one of the things confirmed before a listing goes live.