[dB Cooper]

Wondering what experience the other AC headphone nerds here have with crossfeed. I'll start.

I have never used an analog crossfeed amp like the HeadRoom models, but I have used a variety of digital implementations: Dolby Headphone when I was using a Windows machine, and since moving to Mac, I have something called Canz 3D which is a plugin (VST or Audio Unit). Being a plugin, it requires a host app- I use Audio Hijack Pro which allows me to run any audio on my Mac through it. AHP also has a dry/wet slider which is very useful for 'dialing in' the effect- just drag the slider and and some point the soundstage just sounds 'right'. There are also many controls for adjusting the virtual 'room', ranging from the size and speaker and listener 'locations' to the acoustics of the room. I have never needed to mess with these much though.

Unfortunately Canz3D is 32-bit which means no-go for those running Mountain lion or Lion apps requiring 64 bit plugins (Fidelia being one). VLC though has a 'headphone virtualization' under the Filters tab which sounds pretty good although not allowing the tweaking possible with Canz3D. On the Mac, Fidelia has a headphone virtualization add-on (which I refuse to pay $50 for; waiting for a Canz3D update hopefully).

Who else here has experience with, or thoughts on, headphone crossfeed?

[stereocilia]

I definitely prefer crossfeed for headphone use, which I rarely do.   I wish that my iPod would engage it automatically when the headphone jack was in use and disengage it when I plug into the car.

[hibuckhobby]

I use it both for the imaging improvement and for sort of a 'tone control'.
My Headroom amps all increase the bass and midbass output with the
crossfeed engaged.  That works real well on bass light or thinner sounding
headphones and recordings.  On bass heavy phones (D5000) I turn it off
because it becomes too much of a good thing.
Hibuck...

[dB Cooper]

I kind of find the same thing, it reduces the highs a bit, which is often helpful with my bright-ish Sennheiser 555's. (I often use a slight treble cut when not using it).

The too-much-of-a-good-thing part, that is where the wet/dry adjustment in Audio Hijack Pro comes in. I often back it off a bit from full-on. Like I said earlier, when the soundstage opens up in front of you, you've got it dialed in.

[dB Cooper]

I definitely prefer crossfeed for headphone use, which I rarely do.   I wish that my iPod would engage it automatically when the headphone jack was in use and disengage it when I plug into the car.

ipod has crossfeed?

[stereocilia]

ipod has crossfeed?

not that I know of.  I was just wishing it had plug 'n play crossfeed depending on which plug was plugged.  Sometimes when I wish that something exists I learn that it actually does.

[eclein]

I use whatever type  the unit offers if it sounds good. The Cowon D3 I had with its JET audio stuff was the best I've heard. The D3 sucked I thought but another Cowon could show up again in my cave, I just picked a bad model.
 
Earphones, and mostly IEM's at that, are the only thing in hifi I use any type of EQ on. I have some bass light ety MC5's that shine with a little low end help. Fit is great, sound is clear and the added low end rounds them into an outstanding sound for me.
 

[grsimmon]

I find crossfeed most useful for long(er) headphone sessions, not as necessary for short listens.  I definitely think the idea behind it is sound (no pun intended) and not a gimmick.  Gotta get my wallet wrapped around a SPL Phonitor.....that is THE crossfeed amp to have.

[slwiser]

Crossfeed work very well for me when listening to my Senn HD800 which has a very large soundstage.  The focus can get lost with some music so crossfeed adds to the listening  pleasure for me.  I use my Phonitor when using crossfeed and this is a very good crossfeed design.

[rpf]

I like crossfeed. It sounds more natural to me and I've found that listening to headphones without it for any period of time gives me a headache. I have Senn 650s now but in the past I've had Beyerdynamic 880s and AKG 701s. Sold my Headroom Millet hybrid a while ago and now need a new amp.

[dB Cooper]

Are people using hardware or software cross feed too? I have used only (aside from the one I mentioned in the OP), the FHX add-on to Fidelia, and VLC has a processor buried in the 'Audio Effects' menu under 'Filter'.  Of the three, I like the Fidelia one, which I foolishly paid $49 for, the least. The VLC one is not bad at all.

[stereocilia]

I've only used the foobar plugin; I have no hardware-based crossfeed option.

[ajzepp]

The only experience I've had with crossfeed is my Meier Corda Jazz amp. It's pretty much agreed upon at head-fi that Jan Meier is an evil genius, and his crossfeed filter is a beautiful thing. On the Jazz, it's sort of a crossfeed "lite" compared the circuit he has in both his flagship DAC and amp. I love it because it's very subtle, which allows an already excellent headphone/amp pairing - the Meier Jazz and the T1s - to remain excellent. In fact, I usually don't even notice it until I turn it off. I usually don't like gimmickry, and I'm enough of a "purist" that I don't even use tone controls Equalization is a bad word to me. But I'll trust anything Jan designs, cause the guy is just brilliant.

[eclein]

My ASUS tablet has a crossfeed (Virtualization) sound and I like it and use it pretty much all the time with music, not so much with movies but like Zepp I usually don't realize its effect until I disable it.

JRiver has Crossfeed and I've used it a few times, its a pretty significant change to me....I like it also. I don't think I've heard a hardware one but I'd welcome it. I myself only use eq with portable in ear monitors and nothing else. I find it gives the iem that last little bump in performance it needs to really shine as an iem. My Etymotic iem's are thin in the low end and a little boost makes them incredible sounding. My UE500's come out of the box sounding very dynamic so no eq is needed, but crossfeed stuff I always use. Cowon players have a  nice Crossfeed circuit or software piece and thats been my favorite until my D3 rolled a 7.......I need a JXX next time I think..