foo_dsp_xfeed
2011-09-12 18:50:18
Heya, this is the discussion thread for foo_dsp_xfeed, a Crossfeed DSP component. For those who don't know what that is: it enables a more relaxed and natural listening experience with headphones . A more detailed explanation why and how it works is given below.Download Usage 1) Install the downloaded zip file using the Components preferences page. 2) Add "Crossfeed" to the list of active DSPs (Playback - DSP Manager preferences page). 3) Configure it.Explanation Let's take a look at the image below. When listening with headphones, the left ear only hears sound coming from the left speaker (LL) and the right ear only the sound coming from the right speaker (RR). This often results in unnatural stereo separation or spaciousness and can cause listening fatigue. When listening with speakers, sound from the right speaker also arrives at the left ear (RL), with a small time delay though. This time delay is known as interaural time difference (ITD). Additionally, there's a difference in level known as interaural level difference (ILD). In the image above, line thickness indicates these level differences. In reality, things aren't that simple. The level difference, for example, is not constant because the head obstructs higher frequencies a lot better than low frequencies (aka head shadow). While at low frequencies the attenuation can be as low as and even lower than 3 dB, it can reach up to about 20 dB at high frequencies. To make things more complex, both the ITD and ILD change depending on the angle of the speakers. As the delay and level differences are reduced to zero, the left and right speakers merge into a single center speaker (effectively mono).How is this DSP component different from ... Compared to simple crossfeed effects, this implementation does not only crossfeed bass and lower mids but all frequencies up to Fs/2. By configuring crossfeed levels for both low and high frequencies, this DSP can be set up to mimic the acoustic shadow of your own head. -> For example, hi-hat sounds panned hard to the left/right on a recording can be moved "out of the head" coherently with all the other instruments. The configuration dialog looks like this: Please give it a try and let me know what you think, thanks.