Instruct: Classify Amazon reviews into positive or negative sentiment
Query: So-so headphones, bottom-of-the-barrel microphone.

I recently purchased the Telex H551 to test it for use in a language-lab setting, where students are expected to record their voices for playback by the instructor. We're currently using [price]Plantronics headsets with foam earpieces and bead microphones. The Telex didn't even come close to the sound quality of the Plantronics (which isn't terrific). At [price] per unit, Telex ought to be ashamed of referring to this headset as suitable for voice-recognition, internet telephony, or any other function involving use of the headset mike. On the plus side, the headphones produce reasonable fidelity when playing back audio CDs or MP3s. Perhaps the microphone was an afterthought ...