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Channel Count DSP creates clipping?

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  • MusicTrax
    • Feb 2007
    • 37

    Channel Count DSP creates clipping?

    I just encountered a situation where I've taken several CD mono tracks (identical information on channels 1 and 2) and created lossless FLACs. In order to save space, I've made the FLACs mono using Channel Count in Music Converter.

    Some users are reporting that the resultant files are clipping, though the originals are not.

    My question is: when Channel Count 1 is used in the DSP mode during conversion, does dMC automatically drop the level 3dB to compensate for the summed level? If not, this could explain the clipping.

    In a few cases, I have used Volume Normalization, but I've set it to -.1dB, assuming this will prevent any peaks from ever hitting 0dBfs.
  • Spoon
    Administrator
    • Apr 2002
    • 43898

    #2
    Re: Channel Count DSP creates clipping?

    We just sum, we took the option to not alter the volume in that users can change the dB themselves if required I would recommend:

    Bits (to float)
    Channel count
    Fixed volume adjust
    Bits (to 16)
    Spoon
    www.dbpoweramp.com

    Comment

    • MusicTrax
      • Feb 2007
      • 37

      #3
      Re: Channel Count DSP creates clipping?

      So you're saying the stereo-to-mono mode was done in such a way that users would always run into clipping, without warning them. Interesting.

      You might want to make a note of this in the manual.

      Comment

      • Spoon
        Administrator
        • Apr 2002
        • 43898

        #4
        Re: Channel Count DSP creates clipping?

        Depends on the audio, if it is spoken word (most likely to be down to mono) then it should not really clip (most recordings we have). If you are converting pop music which is dynamically compressed as much as possible, yes it will clip.

        Also it is possible to use the Volume Normalize to never clip adjusting the volume dynamically (peak to peak).
        Spoon
        www.dbpoweramp.com

        Comment

        • Tigerman
          dBpoweramp Enthusiast
          • Mar 2005
          • 157

          #5
          Re: Channel Count DSP creates clipping?

          I would recommend:

          Bits (to float)
          Channel count
          Fixed volume adjust
          Bits (to 16)

          Sorry for kickin' an old topic, but I was looking for an easy way for converting mono songs to one channel without clipping.
          I added the above dsp effects and it works fine, but...

          Is there a way I can add an item to the Converting To drop down menu (p.e. called Flac to mono?

          I convert to flac quite often and it's time consuming adding and deleting the dsp effects each time I need one of the two.

          Comment

          • Spoon
            Administrator
            • Apr 2002
            • 43898

            #6
            Re: Channel Count DSP creates clipping?

            You can save the DSP effects.
            Spoon
            www.dbpoweramp.com

            Comment

            • Tigerman
              dBpoweramp Enthusiast
              • Mar 2005
              • 157

              #7
              Re: Channel Count DSP creates clipping?

              Yes, which is a help, but I want the choice directly in the pulldown menu.
              But from your answer I can deduce it is not possible (yet).
              Maybe something for R14?

              Comment

              • Spoon
                Administrator
                • Apr 2002
                • 43898

                #8
                Re: Channel Count DSP creates clipping?

                It is not possible currently.
                Spoon
                www.dbpoweramp.com

                Comment

                • matt_t
                  dBpoweramp Enthusiast
                  • Feb 2008
                  • 80

                  #9
                  Re: Channel Count DSP creates clipping?

                  Sorry to resurrect a very old thread, but my question is along the same lines.

                  First, bear in mind that what I know about normalisation, replay gain, clipping etc etc would fit on the back of a postage stamp....

                  Take for example The Beatles Past Masters Vol.1, which contains a mixture of mono and stereo tracks. Converting FLAC to Nero AAC (I presume using other codecs such as mp3 would be the same), using DSP effect Channel Count = 1 for the mono tracks, makes the mono tracks sound louder, to my ears. I presume this is because, as Spoon said in post *2, "we just sum".

                  The next bit is where I get lost:

                  1) Bits (to float) - does this mean DSP effect "Bit Depth" -> Fixed Bit Depth -> 32 Bit Float? If not this, then what?

                  2) Channel count - this at least I understand!

                  3) Fixed volume adjust - no clue what this means. Which DSP effect? What settings? Could you give me some idiotproof instructions please!

                  4) Bits (to 16) - as in step 1, but back to 16 Bits, I guess.... Can't imagine what bit depth has to do with volume, but as I said, what I know would fit on a postage stamp.

                  The ultimate aim is to have both the mono and stereo tracks equally loud within the CD. Also, if possible, to arrange it so that if (as in fact I have) I created a playlist on my Walkman of tracks from all the Beatles CDs (I have the old versions, not the 2009 remasters, FWIW) they would all have approximately the same relative loudness (assuming I converted the entirely mono CDs in the same way).

                  I realise that different CDs are made with different levels, but is there a safe/reasonable ballpark figure to compensate for the "just sum" thing? Hope I've explained my question clearly.

                  Thanks in advance, and remember - idiot proof step by step instructions please!

                  Comment

                  • Spoon
                    Administrator
                    • Apr 2002
                    • 43898

                    #10
                    Re: Channel Count DSP creates clipping?

                    1. DSP Effect Bitdepth set to 32 bit float
                    2. DSP Channel count to 1
                    3. DSP Volume Normalize set to Peak to Peak (will set volume which clips down below clipping)
                    4. DSP Effect Bitdepth to 16 bit
                    Spoon
                    www.dbpoweramp.com

                    Comment

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