The Blaupunkt GTt 300 is a 2000s "bass reflex tube" car subwoofer, quite popular in Europe for entry-level and mid-range systems. It is not a radio/cassette player, but a passive bass tube for the car. Main specifications Diffuser: 30 cm (12") RMS power: 200W Maximum power: 600W Impedance: 4 Ohm Sensitivity: 91 dB Frequency response: 35–500 Hz Type: passive bass-reflex tube What it sounds like Powerful and "round" bass, typical of bass reflex tubes. More oriented towards SPL and pronounced bass than towards fine audio fidelity. Very good for: dance hip-hop house electronic music Not considered "high-end", but for its time it had a good price/performance ratio. What amplifier does it need Being passive: needs an external amplifier; ideal: mono or bridge amplifier of approximately 200–300W RMS at 4 Ohm. The manual recommends use with amplifiers from the Blaupunkt GTA series.