[ISSUE]CONTROL ROOM Internal distortion, 32bit floating!

Hi all!
Please DELETE the thread thank you!
Read down further. Found out things during investigations :wink:


http://en.wikipedia.org/wiki/Audio_bit_depth

I think I have found a major flaw in the new Cubase PRO 8 Control ROOM and 32bit floating audio engine. I discover this for quite some time now but wanted be sure before I post anything. Cubase PRO 8 32bit floating audio-engine might have a big issue.

Cubase PRO 8 use a 32bit floating point audio engine. Technically that means that the audio resolution/dynamic are great so internal it shouldn’t peak over 0db on Master bus or any other channels. The head room should be enormous like +192.66 dB over 0db on the MASTER-bus in Cubase PRO 8. But Cubase PRO 8 new audio-engine start to make distorted audio internal already at +6 to +12db over zero on the MASTER-bus? ? I use 32bit floating point on all included audio recordings from 24bit converters. I don’t know of it is a combination about the control room feature?

I did the teat again after the update Cubase PRO 8.0.10. Internal it seem to work now inside Cubase on the new test but as soon the headroom of combination of all tracks “+” and “-” -combination round up +6 db on the MASTER I get internal distortion again?


Please, I know all about gain stage this has nothing to do with that. I know you should not peak over zero internal during mixing and producing. This is not about that. This is very strange technically behavior because Cubase PRO 8 shouldn’t PEAK and distorted internal regardless how much db I add in 32bit floating point environment. The distorted peak should hit at +192.66 dB over 0db? At least not +6db :confused: :unamused:



During testing I have of course no plugins that distorted internal and I have lower the output on all converters and the amplifiers so I’m pretty sure its not analog distortion I hear from the studio equipment. The distortion I hear can only be internal from Cubase PRO 8 audio engine?

I reach out to you experience users. Please try and confirm the issue so we can nail it!


Best Regards
Freddie

If you’re going to make a post like this then you really have to give exact details on what you think the problem is and how to reproduce it. Are you saying you have your master bus prefader signal at +6dB and you then use the master fader to bring the signal level below zero? And that the result is distorted?


Make sure you lower the signal in the DAC/ control room, monitor section and digital audio interface in the studio.
I have found out its about Cubase Control room that make the internal distortion.

\

  1. Make a new project in 48Khz 32bit floating.

2 Add some Stereo Audio track and set track faders to 0db in the mixer.

  1. Rout the tracks directly to the Master bus.

  2. Add Steinbergs Test-generator on one track and set the test generator to send out a test signal in 0db.

  3. Now raise the Control Room —>MASTER Volume to add +6-+12db.

Distortion!



I have provided a screen-shoot to better understand what I’m talking about. I have also added an extra tool to help me add +64db over Zero internal during testing. Check the values inside red.


Best Regards
Freddie


I think I found the issue!! :slight_smile: :wink:
Make sure you lower the signal in the DAC/ control room, monitor section and digital audio interface in the studio.
I have found out its about Cubase Control room that make the internal distortion.

\

  1. Make a new project in 48Khz 32bit floating.

2 Add some Stereo Audio track and set track faders to 0db in the mixer.

  1. Rout the tracks directly to the Master bus.

  2. Add Steinbergs Test-generator on one track and set the test generator to send out a test signal in 0db.

  3. Now raise the Control Room —>MASTER Volume to add +6-+12db.

Distortion!

Please confirm! :wink:

Why are you running your tracks that hot? I would expect distortion if I was running that hot.

I still don’t quite understand the issue. If you have a signal at your master channel peaking at close to 0dB and then you turn the Control Room volume up by 6-12 dB then you will absolutely have a distorted signal because it would now be clipping by 6-12 dB’s at the output of your converter (but NOT clipping at the output of the Cubase mixer so the session will still be bounced without being distorted). If you have your master channel signal at -6dB and then you set the control room to +6dB, there will be no distortion as the final output at your converter will be 0dB. Any higher than that and you will start to clip the DAC of your converter.

As for the internal mix engine in c8, I’ve tested it and it works as expected. No distortion when running signals at very high levels internally (e.g. +30-40dB’s on the channel meters) obviously as long as you are not clipping the master output.

No you should not expect distortion running the tracks that hot -that is the benefit of having a 32Bit floating point mix engine.

There are plugins that cannot handle signals that hot and will cause distortion but the Cubase mix engine itself can handle them without trouble.

On this subject, I have always thought they should change the design of the Control Room so that it reflects what you would hear if you bounced your session. So for example let’s say you have your master channel signal level at +12dB’s. If you bounce the session like this you will have very bad distortion. But if you are monitoring with your control room set at -12dB, it will sound like everything is fine. It would better if the control room signal was fixed point and therefore the signal you hear in this example would sound clipped/distorted no matter how low you set the control room volume.

Thanks for your input. :wink:

After more investigation it can be the DAC /software control panel that overflow internal making it sounds distorted.
I have notice the same as you that it aint distorted as you say +12 and -12 add up to 0db and = no distorted sound.
Internal gain of +64db between channels internal over 0db, are still clean audio, meaning that 32bit resolution are working. :bulb:


Best Regards
Freddie

Please delete my thread thank you!

I have solved it.

Best regards
Freddie