https://www.engadget.com/2012-09-01-sennheiser-hdva-600-analog-headphone-amp.html
Sennheiser unveils HDVA 600 analog headphone amp, asks for $1,600
Sep 1, 2012 - Along with a few IFA 2012 announcements, Sennheiser peeled back the wraps from its HDVA 600 headphone amp, an analog flavor of the previously unveiled HDVD...
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