On Tuesday 11 December 2012 11:11:56 am Alessio Elmi wrote: > @Cowboy: well I was born in the digital era and I am not very > confident with analog/electrical measures. I am learning > step-by-step...
OK. There is one reason to up the levels. ONE ! That reason is noise. All amplifiers have a noise floor. Pick any audio amp. Disconnect and short out the input. Turn the volume all The WAY UP ! What do you hear ? You hear the self-noise of the amp. THE reason to make the content louder, is to push that noise as far down as possible. The louder the content, the less you turn up the volume, the less noise is *added* by that amp. > Apart from that do you think that a CDrip wave normalized ad -13dBFS > could be compromised? I mean in terms of definitions (quantization of > 16 bit depth)... I have an entire catalog that way. The noise floor limit of 16 bit sampling is -96 dbfs. ( zero = fs ) The lower you normalize, the higher you need your output gain. Normalizing at -13 gives you 83 db dynamic range. ( the usable difference between your peak and the noise floor ) Normalizing higher, and risking SEVERE distortion at FULL volume regardless of where your level is set, gives you more range to the noise floor. So, the question becomes what's the maximum dynamic range of all of the equipment after and including your first DAC ? There is no point whatever in exceeding that, because that noise will be present and above the noise of your playback anyway. Humans can have hearing dynamic range that exceeds 100 db, but that means from can not detect, even in a quiet room, to where hearing stops, and real pain begins. It's theoretically possible under ideal conditions for humans to hear the full limit of 16 bit recording, but that means a quiet room and good ears for the low passages, and pain ( not hearing ) at the loudest passages. Theoretically. In other words, if your feeding a really good broadcast transmitter with a remarkable 72 db dynamic range, 96-72=24 db, so normalizing to anything, repeat ANYTHING above -24 is pointless, because all your doing then is substituting transmitter noise for recorded noise, and reducing head room. You are trading head room, and risk of bad distortion, for blinky lights on your meter. Nothing more, because any gain you have at that stage will be lost in the transmitter noise. In a case like this, that extra 10 db of headroom can save your bacon when a "hot jock" drives things to the wall. If you're "broadcasting" over internet, then your maximum range is the typical sound card in consumer gear. About 35 db, give or take. For me and mine, I'd rather stay away from the certainty of severe distortion running out of head room, in favor of the maybe some ONE out there *might* notice a little noise on the quietest passages. -- Cowboy http://cowboy.cwf1.com How long a minute is depends on which side of the bathroom door you're on. _______________________________________________ Rivendell-dev mailing list [email protected] http://lists.rivendellaudio.org/mailman/listinfo/rivendell-dev
