Afficionados of the Philips Fidelio range will be pleased to know that the latest product, the DS 7700, can be used both inside and outside the house. Concatenated with a Bluetooth function for wireless streaming, the DS 7700 can sustain power on its own, away from any power outlets, for at least 10 hours, thanks to its built-in battery. Because of its portability, the DS 7700 has a metal-covered plastic plate that you can magnetically attach over the unit to prevent scratches but it would be even better if a…