Both employ Philips's patented FullSound technology, deliver a claimed battery life of 30 hours (music) or six hours (video), and are equipped with a 2.8in QVGA screen.
FullSound is said to enhance the dynamics, basss, treble and stereo imaging of highly compressed MP3 audio files by restoring them closer to the levels found on the original recording, says Philips. A digital audio algorithm and DSP analyse the sound 10 million times per second to improve the audio signal, resulting in more vibrant, clear and dynamic playback, says Philips.
The 52 series offers support for MP3, WMA and non-DRM AAC audio tracks, plus MPEG4 and WMV video. Each model includes an RDS FM tuner, built-in microphone and comes with a pair of 'high-definition' headphones with Turbo Bass air vents for tighter, deeper bass.