Umm not so sure...
For starters I don't like to EQ. I go for flat line stuff and try to keep my playback chain as pure as possible.(there was a time I wouldn't even consider buying an amp unless it had defeat and pure switches/buttons)
Having another S-master product, I was quick to realise that the DSEE was part of the chip, and it, unlke every other digital EQ I'd played with (outside of special high fi boxes) was kinda perfect.
In fact the european markets version of my Sony Smaster DAP had a lowered headphone output, and I found a nice way to return the volume was to simply drive all points of the EQ up,. and it simply was just raising the volume.
This was not normal in my opinion, but much reading around the net confirmed that the way the DSEE is built in as part of the SMASTER(class D amp), it really is a clean way to do it...
That fact aside of how non screwing with the sound DSEE can be..
plugging in the headset in wired mode sounds no different to bluetooth 3 mode.
perhaps the DSEE is only used in bluetooth 2 or 2.1 mode to restore some of the lost sound?
It actualy sounds much better than any bluetooth 2 device I have listened to (that doesn't feature apt-x for source and headphones).
So maybe it is an 'intelligent' design that activates when needed. It wouldn't have been hard to do (turning it on based on profile of connection) and would make sense. It wouldn't make sense to arbitrarily affect uncompressed sound with a reEq, and as I suggest, they sound the same wired as they do with BT3, so, other than a logo on the box (and remember DSEE is part of S-Master, and Sony would want as much merchandisability of their patents as possible) do we have anything to suggest it is in fact in use?
Recall that the headphones are not using the circuits when in wired mode, so if wired mode sounds the same, and is not being equalised, I put forward that these headphones are without DSEE reEq, though hopefully/perhaps they are when on low bandwidth bluetooth formats!?!
