18V Power Supply Adapter for Bluetooth Speakers, Compatible with Altec Lansin...

I bought this to charge an LED face mask and it works just fine so far

Didn’t work with my speaker

18V Power Supply Adapter for Bluetooth Speakers, Compatible with Altec Lansing18V 2A PSUModel no, J302-1802000BxXManufacturer:Connector: Standard 5.5 x 2.1mm power jackThe PSU is well buil and performed well under load test.I tested the power supply under full load, noting the voltage at different current levels as I increased the load. I then ran the power supply at full load for about 35 minutes, with the following results:load test results .........0A - 17.79V1A - 17.57V1.5A - 17.46V 39C2A - 17.36V 48CThe no load (0A) voltage is just below 18V, but that's not a problem. The voltage drop between 0A and the full 2A load is 0.43V, which isn't bad and shouldn't be a problem.With an ambient room temperature of around 25C, the surface temperature of the PSU was 39C, which is warm and OK. During the 35 minute test at full load, the temperature rose to 48C, which felt rather hot.However, a PSU shouldn't be run at maximum rated load for too long (see Testing below), so I wouldn't expect this to be much of a problem - make sure the PSU has plenty of space around it.This PSU performed well under test, and I found it perfectly satisfactoryTesting information:The standard way that I test many ordinary power supplies is under load whilst measuring the real time Current and Voltage.For this, I use a simple piece of equipment - the Atorch UD18-L This is the UD18 multifunctional inline tester meter, that also comes with a finely adjustable current load. The tester is connected to the relevant supply (via USB, power jack etc. connector) and the load adjusted as required. The display shows the live state of the voltage, and the current being drawn by the load. This is useful if you want to check the power supply's capabilities, such as the maximum power it can supply or the voltage drop over the current range.With a good power supply, the voltage drop at maximum current should be a small percentage of the no load voltage. Poor power supplies often have a large voltage drop at maximum power and may not be fit for purpose if the voltage is too low. Some might even cut out before it reaches the maximum current.I test the power supply under full load for a period of time, usually between 10 - 30 minutes. This is normally plenty of time because any problems usually show within a couple of minutes.It is normally suggested that a Power Supply Unit should not used at its maximum capacity (80 - 85% of capacity is often quoted). Always use a higher amp / watts power supply than the maximum power you require. This gives some leeway and doesn't stress the PSU. Good PSUs usually cope with full power being drawn, but cheap / low spec PSUs may not be able to provide the maximum power stated in the spec and may fail / or give problems such as a large voltage drop, overheat, or cut out. A PSU's rated amp / watts can be higher than you need, as long as it is the same VOLTAGE. E.g. a 5v DC 2A PSU is perfectly suitable to use if you have a 5v DC 1.5A power requirement. Just make sure that the connector is the same type.

This budget power adapter by the rather unpronounceable AmzFwing brand is decent value at the current price of around thirteen pounds from Amazon. There is a list of compatible devices on this Amazon product page but it should work OK with a few other devices with a 5.5 by 2.1mm barrel connector – it outputs 18V at 2A max so check the spec of your speaker or other device. This J302 model adapter is made in China and presented in an unbranded box featuring UKCA, CE & FCC safety logos and is RoHS compliant. The one I received to review does not look like the one illustrated – the adapter unit is different and the there is no ferrite core around the cable to reduce interference. Not a bad adapter for the price but only three stars as it is not as illustrated.