Panasonic wants you to play your music through a good quality portable speaker that doesn't compromise on battery life. It's new NA series claims to have the longest playback time currently available on the market, at up to 20 hours.

Using the iPhone and Android Panasonic Music Streaming app both the SC-NA30 (below) and the SC-NA10 (above) play your phone or tablet's music. The speakers can also be used as speakerphones thanks to built-in microphones. And when you're low on juice the speaker will charge your mobile, via its USB port, even while playing music.

The SC-NA30 features two 2-inch speakers and a sub with a double passive radiator to minimise vibrations. The SC-NA10 has two 1.6-inch speakers and a single passive radiator. Panasonic's XBS Master sound processing smarts combined with components picked for speaker cone efficiency should produce a sound much bigger and clearer than a device of this size would be expected to deliver.

Looking closer at the specifications on the SC-NA30 we've spotted that 20-hour playback applies to long play, and in normal mode it will deliver a still impressive 14.5 hours, while the SC-NA10 manages 10.5 hours on normal. 

Both models are on sale from September with the SC-NA30 priced at £250 and the SC-NA10 at £150.