It seems that the unmix algorithm was changed from 10 to 11, and I’m not sure it was an improvement!
I just ran some tests to confirm what i already suspected (but didn’t have time to test till now), which is that the separation on the bass was better before, in v10.
Now, in 11, there seems to be a lot more bleed from high frequencies from the rest, especially things like high hats and snares… so some residue of these elements sneak their way into the bass stem (even at the “extreme” unmix setting).
This really is a problem, because i used to do things like high-shelf the bass up to get some more bass clarity, but this isn’t possible any more because then you’re also boosting these high frequency elements that unpredictably sneak their way into the bass stem.
It would be great if others could also check this (easily done i guess with an older project where you can also unmix it with 11 and compare to 10).
I only checked the bass, but it could be this less-good separation manifests itself with the other stems.
Many other sounds bleed into the bass layer, even middle range of the piano as can be clearly heard in the “Coldplay - Clocks” example. There may also be some bleed in the opposite direction (some bass gets lost in other layers), but I am not that sure about this one, it’s just a hunch. In addition to bass, I had a case of percussions bleeding into the “Other” layer.
Generally, Logic’s stem splitting is so much cleaner in my experience on practically any song I tried. SL may technically be more accurate for remixing purposes, I can’t claim anything about it. But purely musically speaking, stems that Logic extracts are actually pleasurable to listen in isolation, while in SL everything gets somehow blurrier, harsher and screechier, not really sure how to explain it. I realise that this may very well be a subjective experience. My ears may simply be more sensitive to something that SL does. A good workflow compromise for me is to start stem separation in Logic and then move the unmixed parts to SL for further automatic or manual unmixing.
Perhaps there was an effort to keep more high frequency of the bass instruments in the bass stem, which in theory is laudable…but the bleed i’m hearing is from rhythmically unrelated elements.
So unfortunately i’m going to have to go back to SL10, although I’ll really miss the batch functions of SL11.
@the Devs, maybe you could give us the option in SL11 to switch back to the SL10 algorithm if we want?
There’s a commercial program out that, on its dropdown menu, shows a LOT of choices labeled “demucs this” “demucs that”…bunches of them. Pretty much labeled same as whatever they were/are on github.
A guy posted that there were TOO MANY choices on the dropdown on that program…and he doesn’t feel he has time to go through all of them to find which works best on “his” source tracks.
His comment was there should just be a “best one” to instantly select.
Goes to show, you just can’t please everyone no matter what you do
