http://www.sengpielaudio.com/calculator-db-volt.htm
On 12/12/12 04:15, Bill Putney wrote: > 1.0 in Audacity is 0 dBFS. This has nothing to do with voltage. It has only a > tenuous relationship to 0 dBVU. Various people use various values for 0 dBVU. > Usually it's -18 (EBU recommendation) or -20 (AES recommendation) down from 0 > dBFS. > > Now we kinda get to voltages. 0dBVU is +4 dBM (1.23V RMS at 600 ohms) in pro > systems. 0 dBVU is -10 dBV (.316V RMS). > > Bill > > On Dec 11, 2012, at 17:47, VE4PER/ Andy <[email protected]> wrote: > >> Noticed lengthy discussions on normalization and found this chart that >> might be of interest >> >> >> http://www.google.ca/url?sa=t&rct=j&q=0%20dbm&source=web&cd=4&sqi=2&ved=0CD4QFjAD&url=http%3A%2F%2Fwww.tecmag.com%2Fpdf%2Fdbm_v.pdf&ei=fN_HUK2TGIaE2gXlxoCgAQ&usg=AFQjCNEY25QxasGndqL5ZAXkYDCgFaB4KQ&cad=rja >> >> >> also this explanation I found useful >> >> http://en.wikipedia.org/wiki/DBm >> >> Audacity shows a scale with 1.0 as a max usually but that is PEAK only >> and is actually 2.0 VAC Peak to Peak >> >> RMS is 0.775 and average is closer to 0.5 so be sure to compare >> apples to apples and oranges to oranges >> >> >> I have a portable oscillator for aligning my mixer board and all other >> audio sections including the PC's but only have a standard digital >> multimeter and or a standard analog mutimeter neither of which are >> calibrated to read in db, dbv or dbm unlike a lot of pro audio test sets >> are so these relationships help to be able to use the basic meters to >> calibrate my systems; but one has to be very aware of the relationships >> and not to confuse, peak, peak-to-peak, average and RMS values in order >> to maintain a maximum peak range between -8 dbm and -12 dbm and still >> retain a further 4 db of additional headroom for protection. >> >> >> >> >> >> _______________________________________________ >> Rivendell-dev mailing list >> [email protected] >> http://lists.rivendellaudio.org/mailman/listinfo/rivendell-dev > _______________________________________________ > Rivendell-dev mailing list > [email protected] > http://lists.rivendellaudio.org/mailman/listinfo/rivendell-dev > > _______________________________________________ Rivendell-dev mailing list [email protected] http://lists.rivendellaudio.org/mailman/listinfo/rivendell-dev
