Assertion: headphone | /r/HasProperty | driven with an ipod touch
Facets:
Source sentences:
text: For example, a 32 Ω headphone driven by a headphone amp with a <1 Ω output impedance would have a damping factor of >32, whereas the same headphone driven with an iPod touch 3G (7 Ω output impedance)  would have a damping factor of just 4.6.