Stems experts!


I’m going to be getting my music mastered from stems soon.

I used Cubase’s Export functionality to mix down 4 stereo stems - drums, bass, guitars and vocals.

I then took a stereo mix of everything, taking care to disable buss compression on the stereo output for all the above.

I then went into another project to see if my four stems sounded like my stereo mix, but found that the sum of the 4 stems was a lot “louder” than the single stereo mix.

I was surprised at this as all group busses that were generating the stems are set to 0db and the stereo output is 0db too.

I was expecting them to sound the same.

Is there an explanation for this disparity in volume?


The disabling of the bus compression?

Hard to tell with that vague info on what you exported via which bus. But you’ re probably doing something not correct.

Sorry - no the stereo buss compression was disabled for all the outputted files.

Exactly how did you use the export mixdown function? Please describe in precise detail.

You are not comparing the same audio. In the original project, try creating the stereo mix via the group busses you used to create the stems.

I had the same problem recently. I found the sum of all my stems to be 2.75 db louder than my single file stereo mix. I couldn’t resolve my issue, so I just lowered my master fader 2.75 db. I don’t get it either… Anybody have any ideas?


Are the pan laws the same?

Not sure if this is related, but when I export and re-import a track, say a vst drum track, I always feel like it comes back in hotter than I originally had it mixed in the song and have to turn that imported track down, also having muted the vst track. I think there’s something we’re missing or there is something funny going on.

You must be missing something!

Hi Nexis

It’s quite strange because when I export the busses through the stereo output but, one at a time, the sum of the consequent audio “matches” the stereo output I’ve taken of the entire mix. I’ll probably just have to do it this way in order to “quality assure” that the stems I am giving to the mastering studio “add up” to the stereo mix I’m giving them as a guide.

Thanks for your advice.


Do you have Control-Room configured correctly?

As Split suggests you may be having an issue with pan law. I would add that you are almost certainly overlooking a fader level or some other parameter somewhere. This kind of thing is almost always down to user error. It’s so easy to overlook something when you are exporting and importing. The classic case is confusion with fader levels when not set to 0dB unity gain. Trust me, Cubase does not make any error at all with levels when exporting or importing.

Nothing funny going on. As I mentioned above, Cubase does not make mistakes with levels when exporting and importing, it’s just following what you set up. I would suggest that you prove this to yourself by conducting an experiment in a new project. Proceed as follows:
1 - import 4 stereo audio files onto 4 separate stereo tracks
2 - add 2 stereo group tracks
3 - route tracks 1 and 2 to group 1
4 - route tracks 3 and 4 to group 2
5 - route the group tracks to the main stereo out
6 - make sure that ALL faders are set to 0dB, including the main stereo out!!!
7 - set up the left and right locators around the relevant audio
8 - use export audio mixdown to mix down one file for group1 and another for group 2 (activate channel batch export and tick Group 1 and Group 2)
9 - activate ‘import into project / audio track’ to automatically re-import the exported group tracks onto two new stereo audio tracks within the same project
10 - now compare the levels of the original groups and the newly exported/imported files (once again all faders set to 0dB).

You will find that the levels are identical both for the groups and their corresponding exported file channels, and for the resulting peak level on the stereo output. There is no mistake with this.

Hi stingray,
Thanks for your suggestion, I can’t set all of my faders to 0 db because I’ve worked so hard on my mix. I am suggesting that the exported stereo file that comes out of my master bus does not equal the volume level of all my exported stems.


You do understand that you’re hiring a mix engineer and doing some grunt work for them, right? This idea that “mastering” involves stems is a comment on how people think they can mix but can’t.

Not that I’m bitter…as a mix engineer :wink:…having people sold something other than what they are giving. If the mastering engineer told you he needed to remix your song, you’d say…? That’s what he’s doing. call it what you want. You give me a drum stem, I can completely change the balance of the kit. Same for most stems. Or groups as we call it when we MIX.

I feel for them…they don’t want to be doing it…but, people can’t accept that they don’t know how to mix…but somehow, doing a little squeeze/M-S EQ/clip is some f’n dark art they are willing to pay for.

I’m gonna change my business. I’m now doing mastering. Send me all your 100 tracks and I will “master” them into a nice sounding stereo file.

Hi Nexis,
No, I was not suggesting that you set all your fader levels to 0dB for your mix, I am merely suggesting that when fader levels are not set to 0dB this often leads to confusion when you export a group channel or any other audio channel, and then import the resulting audio file into the project.

For example, if you export a channel whose level is boosted by 3dB, then the resulting audio file is also boosted by 3dB. If you were to then import the resulting audio file into the project, the fader for the channel must be set to 0db in order to achieve the same level as the original.

So let me put this another way. Are the group channels of your mix set to levels other than 0dB at the time of the export? I’ll say yes, they probably are. When you re-imported them into the project, did you set the faders for the channels of the imported files to 0dB unity gain?

In the same manner, are the master fader levels set to a level other than 0dB at the time of the export of the stereo master file? I’d guess yes. If that is the case, then importing this file onto a stereo track in the same project will NOT give you the same level unless you reset the master faders to 0dB unity gain. Did you understand this subtlety? This last point is frequently overlooked.

So I understand exactly what you are suggesting about the exported stereo file that comes out of your master bus does not equal the volume level of all your exported stems. However, you are almost certainly overlooking some detail, since where levels are concerned Cubase does not make mistakes. I have seen this stuff hundreds of times, it’s just so easy to overlook something about levels when importing and exporting audio. Try re-examining the process you used to export the files. Did you import them back into the same project? Did you set the faders to 0dB unity gain on the channels you imported them onto? At the time of the export of the stereo file of your master bus were the master faders set to some other level than 0dB? You’ll find the answer in there somewhere, but to get any more help here you are probably going to have to explain what you are doing in PRECISE DETAIL.

Hi Sonik

Thanks so much! In my specific instance it looks like Control Room levels not being 0db created my problem.

Thanks to everybody whose participated in this conversation - I really appreciate the help.


Cool. The more gain stages introduced, the more complicated it gets. I hate that when I export and turn down the preview volume (to go get coffee…) and come back, open a different project, Cubase leaves the Control Eoom volume at whatever I set the export preview to…always takes me a few seconds of going “why is everything so quiet?”…before realizing…they should really set it back to whatever it was prior to export.

No, they should not…


Well, I don’t have any group channel in my project and the master fader is set to 0db. My control Room is also set to 0 db… I need to check to see what my pan law is set to :slight_smile: