From: Brian Wolven <bcwolven_at_jhu.edu>
Date: Thu, 24 May 2007 12:49:33 -0400

Brian Wolven wrote:
> Robert Menes wrote:
>
>> But it could also be the headphones you use. Try another pair.
>

Follow up to this - the hiss is much reduced with Sennheiser HD497's (32 Ohm).
With Sennheiser CX-300's or Sony MDR-Ex51's (both 16 Ohms) it is highly
objectionable. With the 497's it's at the same level with the 30G video as it
was with the mini and the CX-300's, i.e., it's there, but you really need to be
in a quiet place in order to hear it. It seems like the headphone impedance is
the important factor here. There was some discussion on the rockbox IRC logs
suggesting that there was less hiss in the headphone output with rockbox than
with the Apple firmware, perhaps due to the different power management. I
haven't done any testing of this yet, however. Anyway... I guess I'll hang on to
the iPod and pick up an attenuator, since the 497's are great for the home but
too big for traveling.
Received on 2007-05-24