Music and Phone Calls via Bluetooth at Home

Siemens has developed a small Bluetooth-enabled device that allows to make cordless phone calls and listen to music simultaneously. The Gigaset ZX1 consists of a communicator with a button for accepting incoming calls, plus wired stereo headphones. When wearing the headphones, users can listen to music at a distance of up to 100 meters from the stereo or other audio source. If they receive a call, they simply push a button to start talking. It’s often the case that people miss phone calls because they’re either wearing headphones or have turned up the stereo to listen to music while doing housework or exercising.

The ZX1, which is about the size of a cell phone, is linked to a phone like the Gigaset SL 560 — or a cell phone and Voice-over-IP (VoIP) Internet telephone — via the Bluetooth short-distance radio system. To compensate for quality fluctuations (especially with VoIP), experts from Siemens Home and Office Communication Devices developed what is known as DSP2 technology, which suppresses disturbing noises by means of special algorithms that filter out all types of interference, while accentuating voices.

The developers also split the Bluetooth channel into two frequencies, which is what enables the rapid switching back and forth between talking on the phone and listening to music. The signals from the audio source — whether a stereo, TV or MP3 player — are also received via Bluetooth. To this end, an adapter (ZX2) is fitted to the audio source’s outlet socket for the headphones. These ZX2 adapters automatically connect with the ZX1 unit. The ZX1 is equipped with a conventional 3.5-millimeter pin socket to ensure CD-quality sound no matter what types of headphones are used.

The Gigaset ZX1 will go on sale in April. It will cost €139 in Germany , or €159 with the ZX2 Bluetooth adapter. As a next step, the Siemens developers are now planning to split the Bluetooth channel into four streams, which will enable users to choose from among three audio sources and their telephone