Sennheiser CX 300S vs Sennheiser CX 5.00i: What is the difference?
Sennheiser CX300S - Frequency response database
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ConnectIT - Boost your sound with Sennheiser's CX 300S earphones which offer amazingly detailed sound reproduction and enhanced bass response thanks to Sennheisers transducer technology. The in-ear design reduces ambient noise to