Fascinating. Headphone users are using DSP to add stereo crosstalk and loudspeaker users are using DSP to remove it.
...adding a delayed, equalized signal is easy to do compared to crosstalk cancellation.
But that's precisely how crosstalk cancellation is done except the added signal is inverted and applied to the opposite channel.
I'm putting the finishing touches on an Ambiophonics plugin for foobar2000 and I've observed none of the deficiencies you claim.
I'm glad you enjoy it as much as I do.The defaults (-3, -12 dB and 250 us in v0.1.1) aren't perfect and also don't work with every head. The low frequency crossfeed level isn't that critical because the time delay and resulting phase shift is more important in that frequency range - to our hearing anyway. Additionally, many recordings (except the ones you mentioned) already have bass in the center so this value can be increased to your liking.The high frequency level should be lower in theory because if you look at some 30° HRTFs you can see average level differences of roughly -18 dB. Though these HRTFs are measured in anechoic chambers. My component doesn't add reverb (yet) so I increased the default to account for that.The time delay also is based on averaged 30° HRTFs, but is highly head-shape dependent. You can approximate this value with: ITD = d/(2 * c) * (a+ sin(a)) where d is your head's diameter (in m), c is the speed of sound (~343 in m/s) and a the angle (for example 30°/180*pi, in rad). As you can see this simple model assumes that your head is spherical.
There are records where, e.g. in the beginning of a track, one channel is basically silence (below -60 dB anyway) while the other contains some loud instrument. In no way you'll hear something like that in the real world and neither did the artist or engineers because they listening to it on stereo speakers without any crosstalk cancellation.
Thanks for the explaination. I couldn't quite folow the equation but that wouldnt be the first time...I you'd feel like breaking it down further for me it would make me very glad.BTW I'm now routing my broswer and video player throught FB2K to make use of your crossfeed plugin. Consider me a fan
I'll never know what the artist or recording engineer heard nor do I care.
Most stereo recordings have center channel information that is common to both channels. The comb-filter and related effects are the damage done by stereo crosstalk. I find reducing those effects beneficial; you find the opposite.
0.15/(2 * 343) * (0.524 + sin(0.524))
Does your component use frequency-dependent ITDs?
BS2B definitely isn't simple crossfeed component, it does use frequency-dependent ITD, doesn't suffer from comb filter effect as it isn't FFT based and it is my favorite non HRTF headphone DSP.
However , i'd be curious to know your opinion about TB Isone when compared with xfeed.
Thanks for this.It's interesting to find and try out new crossfeed plugins! I've used quite a few since getting my headphone amplifier in 2004 with built-in crossfeed.