Sound Science Forum Moderator
- Jul 2, 2011
if the usual variations are within the range of variation they always had on the hd650, then there is no reason not to treat them as the same headphones. before wondering why they don't communicate on the changes you feel you have on your pair, I believe it would be relevant to learn about the manufacturing standard for a hd650 or hd6xx. we know they try to match left and right drivers within +/-1dB when paring them, but what is the accepted range of responses before a driver is deemed defective and just discarded, instead of being put aside waiting for a close sibling to be matched with? same for final construction and pads, I have no idea what tolerances they follow.I don't think HD6XX is HD650, at least not an older version I've had. If there has been update to the driver over the years to HD6XX, I'm quite ok with it (I much prefer it over what I recall of the HD650). I just wish Sennheiser can just be transparent about it if it was the case.
I wish somebody can confirm. Maybe somebody has some evidence from the internals?
the few measurements I've seen certainly look like what I've gotten used to expect from a hd650. but I don't know how much effort was put into trying to get the same signature by the people making those measurements, so I'll reserve my judgement on that.