The basic idea is to allow the listener to hear a recording through headphones as it was intended to be heard through speakers.
Not really. The basic idea of crossfeed was just to approximate some of the acoustic crossfeed which occurs when listening to speakers. However, there’s a great deal more occuring when listening to speakers than just acoustic crossfeed, there’s obviously a far greater distance between the listener and the speakers which causes numerous other acoustic effects besides just acoustic crossfeed, room reflections and interactions with those reflections for example, that crossfeed does not even attempt to replicate/approximate.
I find crossfeed generally improves the three-dimensionality of music - creating a better sense of being located in the audience at a performance that is occurring forward of the listening position. I find this improves imaging and timbre of acoustic instruments quite significantly.
I find the exact opposite, worse imaging and sometimes phase effects that negatively affects the timbre of instruments quite significantly.
Having tried many versions I've come to prefer the 'analogue' approach; that is, implementing a crossfeed circuit in the amplifier.
There is no difference of analogue vs digital, there’s just different implementations of crossfeed regardless of analogue or digital.
It's surprising to me that there isn't more interest in this …
It’s not really surprising, for 2 reasons:
1. Crossfeed is a relatively old technology, dating from the 1960’s and how well it “works” (or doesn’t) is highly variable, because it doesn’t only depend on the audio/music to which you apply crossfeed but also on individual perception. While a significant percentage of people perceive soundstage/imaging and timbral improvements, the majority don’t. That’s the main reason it never really took off in the first place.
2. The relatively basic/simplistic approach of crossfeed was superseded by a far more sophisticated and comprehensive approach, HRTFs (Head Related Transfer Functions). The processing power of modern devices allows HRTFs to be implemented even in mobile devices, in addition to convolution reverb and head tracking, which really can (under certain conditions) replicate the speaker listening experience. This is where the “interest” is, and where a number of huge companies have been throwing their R&D budgets for a number of years, rather than on an old, superseded technology.
I often encounter the very dismissive view that it simply 'wrecks' music, is a 'scam', a 'waste of time' and 'damaging' to recordings. I've no idea why mention of crossfeed so often elicits this kind of reaction ...
Because of the above! While crossfeed definitely wasn’t a ‘scam’, it does in a sense wreck or damage music but as mentioned, some/many will perceive it as damaged and others will perceive it as the opposite (an improvement), although there are also some who will occasionally perceive crossfeed as an improvement (depending on the recording) but far too rarely to justify it’s use. Such a polarised response/perception will inevitably result in “
this kind of reaction”.
Incidentally, just in case my response above is taken by those who do prefer crossfeed as some sort of insult, that is NOT my intent! There is nothing inherently inferior (or superior) in those who perceive an improvement with crossfeed. Not only do we all have different HRTFs but the acceptance/adaptation of our perception varies from person to person.
G