M4 pro chip:
14900k + 3070 GPU:
known issue apparently…? Is there an update in the pipelines?
known situation…tag @Robin_Lobel in an effort to investigate whether or not any changes to current status 
I’ve just sort of gotten used to the slow speed of processing when unmixing.
It is a little disconcerting that this is a well documented and well known bug, but there have been no updates to the product since November!
It’s not a bug.
Unmix Song has always been slow on Mac/M-series computers, that unlike Windows machines have no separate GPU. Since day one.
Steinberg has admitted that this is a bug. And yes, M-series Macs (like my Mac-mini) do have separate GPUs:
@Marshall @scott_bernstein To my understanding it’s not a bug but a limitation of the cross-platform compatibility of SpectraLayers and what Apple offers on MacOS.
But stems separation models have a degree of complexity that simply doesn’t run on CoreML, the mac acceleration technology that SL primarily use. Apple did not design CoreML to handle tensors that have dimensions higher than 16384 in size, which several AI audio models use. Every year I talk to Apple in hope they fix their AI model converters for complex models so I could use other Apple technologies, but they simply don’t. And I’ve been in talk with them about this for at least the past 3 years.
And for whatever reason they don’t want to use Python and Pytorch, which seems it could solve this problem. Probably because it wouldn’t be tightly integrated into SpectraLayers but works as an external environment.
To my knowledge the GPU is integrated in the M-chip and not separate like in Windows machines or earlier Macs.
The way the Macs handle the use of the GPU part makes it harder for 3rd party developers like SpectraLayers’ to make substantial use of it, as far as I know.
It is not a bug. A bug to me is an malfunction in software that appears unbeknownst to the developer and unintendedly. The slow performance of SL in M Macs is about not being able to reach the deeper GPU functions, for different reasons, and this was very clear to the developer when the Unmix Song functions were implemented several years ago. The distinction between this and a bug is more than only a semantic question.
Was it not the case that unmix was able to use GPU on M series Macs (and I genuinely don’t know the answer to this because I only recently purchased an M series Mac) in version 11?
@scott_bernstein SpectraLayers used different AI models in the previous versions. I believe at first they used Spleeter for stem splitting, then Demucs. Now they use a combination of different models. I think especially enabling saxophone splitting is very slow. It might run faster if you only split vocals and the rest and don’t use the high quality mode.
No, it has never been possible for SpectraLayers to use the GPU portion of the M processors I’m afraid.
I bought an M1 Mac 2022 and remember I got disappointed that it didn’t handle the GPU related tasks in SpectraLayers Pro 9 then.
Initially it seemed like the developer had some hope to get Apple to make it easier or possible - I don’t know which - to implement GPU processing but each new version has unfortunately been a disappointment in that respect for us Mac drivers.
Still love and use SpectraLayers extensively though.
Robin DID post a fairly extensive reply here months ago (or maybe at gs) of the issue(s) with Apple the silicon hardware and dealing with the company.
I’m not code savvy enough to quote the situation, but I took it from the post that Robin was/is dealing with Apple to allow something or other (in code/hardware access) that they (Apple) were/are…not allowing for anyone on the planet outside of their own Cupertino inventions. A control thing…in my opinion…in my opinion…in my opinion!
I won’t even get into my personal opinions of Apple after dealing with them myself corporately since 1988.
But hey, I understand that if I own a recipe for an enchilada that no one seems to be able to reverse engineer, I’m gonna guard that like Ft Knox in my restaurant and do everything I can to prevent outside access by parties who want to add their own guacamole topping that neighbors are clamoring for with that enchilada
Ha…I don’t know Robin at all (hope he comes out here to a Namm show someday)…but what I dread is the idea that Apple gets tired of dealing with it, and buys him out from Steinberg…which yikes…we all know what that would mean!!! (rip Emagic)
That’s right, he didn’t get any help from Apple at all, as I remember it.
I wouldn’t mind if Apple recruited Robin for coding SpectraLayers under their hat.
Apple is a massive monopoly that locks you in to its products for life. Get out when ever you can. Apple wanted 100 USD-dollars (Hi Davie504) for a watch cover… (yes, a watch cover, the little silicone thingy that is injection-molded in milliseconds, and the same exact thing you can get aftermarket for 2.99 USD-dollars) over a year ago, is it 10k now?
Apple machines are locked from their owner’s control. Especially the hardware: Want to build your own awesome Apple? Fat chance. You have to buy what they tell you to buy. I choose freedom, and walk away from anything Apple.
Do yourself a favor, ditch your Apple “Pro Macbook” (reminds me of the ‘biggie fries’ gimmick) and build yourself a real machine that can take advantage of every awesome feature that SpectraLayers has to offer, and for a lot less money, especially if you build it yourself or have it built to spec for you by a professional (there are tons out there). Then enjoy the fact that you can modular-ly upgrade and update its components at any time in the future, and actually choose which manufacturer you prefer for each individual upgrade… oh yeah, and be able to actually choose to utilize the full power of your GPU… so, there’s that.
No fee for this incredible advice. 
If SL performs noticeably slower on a MacBook then Steinberg and @Robin_Lobel should make it damn clear on the Steinberg website that this is the case.
When I read the System Requirements section online I see nothing about it being slower.
Get it to work on the MacBook GPU or change the website. I don’t get how it is this way in 2026.
haha…how to quantify that on a spec sheet?
Simply put “GPU accelerated processing” as a parameter and then list the requirements with a special note that one of the most popular portables can’t do it.
It’s 2026, it should either work on both Win and OSX or it should be noted as such. Like, wtf?
Dude’s got a point. Just sayin’.
(I couldn’t help myself, I fixed the E to an A in the quote. 5 pts if you guess where)
Oops!
Thanks, I appreciate the precision, ‘precision’.
Normally I’m better then that, so I should of known I made a mistake. They’re will be mistakes from time two time sense I’m human. Hopefully it didn’t hurt your eyes and brane to much.
I got lotsa chucks from that, thanks Eddie!
(I still say you have an excellent point)