How much does headphone bleed concern you? A folk group I was mixing months back had an upper freq problem that drove me nuts. After listening for hours, trying to de-ess but at the same time trouble shoot for the sake of "next time they go into the studio!" it will be better than this mess! I continued asking the producer to keep trouble shooting what the high end swirl was caused from, he blamed the recordist, the gear "" then I finally discovered multiple vocal takes had various version of headphone bleed. So I asked him, "did you sing harmonies to lead lines that aren't here now, or that were changed? Pitches aren't lining up on bleeds." In other words, the final harmonies I am mixing, were sung to a lead line now scratched. This was the same for guitars, bass , drums etc! How do I know this? Again, because I hear those tracks from headphone bleed. What this was is a work in process that became a song ready for mixing and mastering. This is a common way many people create music in a studios today. We build a song and instead of actually learning the whole thing over, redoing it all over again start to finish, we leave it and mix it best we can. There is a major problem with this and its in the headphone bleed. The bleed from all these parts is still in the background. It can be so soft on one track but throughout mulitple versions as described above, will cause all sorts of upper freq swirling effects that become a de-essing nightmare.. Does this make sense? I hear this all the time. The nightmare of digital editing and headphones bleed. Its in most tracks I get here and maybe we should be talking about this a bit more? Usually the worst of it gets chopped out during the silent parts so as a mixer coming in on something blind, you don't hear it all. Why do you think we have so many issues with sss? Imagine Hi Hats ticking away in everyone's headphones. They are cutting through the headphones and capturing how many times? They are in the lead vox, harmonies, guitarists playing to vocals and drums etc. Start over dubbing, moving tracks around, compounding this. Now we have parts of parts, aux bleed along with instrumental bleeds, even bleed being picked up from the acoustic guitar box's adding low end and out of sync, out of tune parts to this. I mean, they are acoustic instrument with different days that obviously aren't tuned exact to the last session. It would be fine if everyone was playing all together but how many of us do that anymore? The Harmonies and lead lines get sung and pieced together from all sorts of takes of guitars, drums, harmonies etc all the time but how many of us really know what this does to the phase and transients. You can't autotune out of tune vocal bleeds so be sure what you play to, is the vocal track you are keeping, because if you don't, even though you changed the vocal down the road, the deleted one will still be tracked on some part . These accumulates like a virus. If you've ever lined 2 tracks up by finding the top of the peak. I do this with headphone bleed. I will often listen to the bleed on tracks and line the headphone ticks up. Does this ever teach you something about phase and where ss are coming from!