While -16.9 might keep you safe, a better option might be -20 dBFS. Gives some headroom in case you need it. Also, many consumer playback devices may not handle full scale output.
> On Sep 23, 2013, at 11:00 AM, sursound-requ...@music.vt.edu wrote: > > Send Sursound mailing list submissions to > sursound@music.vt.edu > > To subscribe or unsubscribe via the World Wide Web, visit > https://mail.music.vt.edu/mailman/listinfo/sursound > or, via email, send a message with subject or body 'help' to > sursound-requ...@music.vt.edu > > You can reach the person managing the list at > sursound-ow...@music.vt.edu > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of Sursound digest..." > > > When replying, please remember to edit your Subject line to that of the > original message you are replying to, so it is more specific than "Re: > Contents of Sirsound-list digest..." so that it matches the post you are > replying to. > > Also, please EDIT the quoted post so that it is not the entire digest, but > just the post you are replying to. > > > Today's Topics: > > 1. Re: Volume question WRT 7.1 sound recorded at listening > position. (dw) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Sun, 22 Sep 2013 19:53:35 +0100 > From: dw <d...@dwareing.plus.com> > To: Surround Sound discussion group <sursound@music.vt.edu> > Subject: Re: [Sursound] Volume question WRT 7.1 sound recorded at > listening position. > Message-ID: <523f3caf.4040...@dwareing.plus.com> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > >> On 22/09/2013 12:51, Andy Furniss wrote: >> Hi >> >> I do not have a 7.1 sound system so can't actually test this, also as >> may become apparent I don't know much about sound :-) >> >> I would be grateful if someone could correct/confirm the following. >> >> If I were to mix down a digital 7ch to mono I have to reduce by 1/7 >> amplitude to prevent clipping, so one channel will be -16.9dBfs. > This assumes that all 7 channels are driven with the same maximum level, > in phase, and that this would get past the mastering stage,, > I'm sure they bear in mind the possibility of stereo, or mono mixdown. >> >> If I play the track over one speaker the volume difference between one >> and all channels will be 16.9dB. >> >> If I were to measure the volume at listening position (assuming >> anechoic and equal speaker distance) with a real 7 speaker setup then >> the volume difference, because the speakers are not close, would add >> up using power not amplitude so the difference heard/measured between >> 1 and 7 at full power would only be 8.45dB, so there is quite a large >> dynamic range discrepency? > > You would add powers if the 7 channels had random relative phase (which > is less likely with "anechoic and equal speaker distance" > >> >> The real reason for this question is more to do with simulation than >> real life, so perhaps that will make a difference - if the speakers >> are infinitely far producing planewaves and a soundfield is at >> listening position would that change anything for what levels the >> virtual omni would "hear". >> >> TIA >> >> Andy. >> >> >> _______________________________________________ >> Sursound mailing list >> Sursound@music.vt.edu >> https://mail.music.vt.edu/mailman/listinfo/sursound > > > > ------------------------------ > > Subject: Digest Footer > > _______________________________________________ > Sursound mailing list > Sursound@music.vt.edu > https://mail.music.vt.edu/mailman/listinfo/sursound > > > ------------------------------ > > End of Sursound Digest, Vol 62, Issue 15 > **************************************** > _______________________________________________ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound