-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 rotter supports FLAC, WAV, MP3, Vorbis. I've been using it in production for lossless (4-week) archives and lossy (6 month) archives for over a year and a half now. It's stable and works flawlessly.
Cheers, James Harrison On 05 August 2012 15:27:38, Chris Cramer wrote: > Right. I forgot: rotter suports higher bitrates but no high quality > encoding... > > On Sun, 5 Aug 2012 16:15:32 +0200 > Chris Cramer <[email protected]> wrote: > >> Hi Wayne, >> >> I shrink the Audacity window to a minimum, so it ain't no problem pressing >> record in due time and cut the beginning second w/o audio signal afterwords. >> Rotter works automatically according to its internal time schedule (every >> hour a new file) as far as I understand. >> In addition it produces .mp3 in 128 kBit only - witch is way to poor for >> professional FM broadcast quality. >> It is a nice tool for documentation purposes though. >> >> Cheers, Chris. >> >> On Sun, 5 Aug 2012 14:50:47 +0100 >> "Wayne Merricks" <[email protected]> wrote: >> >>> Lots of good info here, regarding Audacity for recording. Would something >>> like rotter be easier considering you could automate it? Having to click >>> record in Audacity seems a bit clunky to me or is there another mysterious >>> way of using Audacity that I don't know about? >>> >>> >>> -----Original Message----- >>> From: [email protected] on behalf of Chris >>> Cramer >>> Sent: Sun 05/08/2012 13:39 >>> To: [email protected] >>> Subject: Re: [RDD] RMS levels (some definitions) >>> >>> Hi all, >>> >>> About levels, >>> >>> this is a part of the mastering process of a recording and there might be a >>> reason why this is still done manually in the CD production process. >>> Never the less as fas as I know there is only one product in the market >>> that is able to calculate and display a volume level of an audio signal. >>> That would be the Peak Program Meters (PPM) from RTW. And that is only a >>> display, not an algorithm for sound processing. >>> This does not exist yet (as far as I know) as the material that is supposed >>> to be processed might be of totally different dynamic nature. >>> A voice track has an other dynamic range than a classical music track or a >>> techno club track or a rock ballade for example. >>> Therefore it is nearly impossible to pre program a one-fits-all algorithm. >>> In my studio I do have a Jünger Audio digital dynamic processor that I use >>> for vinyl copies or raw audio material that was recorded live that has to >>> be processed. >>> In my cart library I process manually watching my external ppm and USING MY >>> EARS to find a matching level. >>> As I mainly use RIVENDELL for pre production I process the final show using >>> the JACK plugin JAMIN witch performs very good (without any pumping) to >>> produce a -0.2 dBFS audio stream I record using Audacity at the same time. >>> When finished I export the recording as .wav and process it with lame in >>> high quality. This file is then uploaded to the dropbox of the broadcast >>> computer and then aired as scheduled. >>> >>> About working levels >>> I hear different opinions about levels in this group. >>> >>> There are clear definitions about levels in a professional broadcast >>> environment. >>> >>> First: 0 dBFS means the maximum level w/o distortion in a digital >>> environment (FS = Full Scale) >>> >>> In the area of the European Broadcast Union (EBU) the following levels have >>> been agreed on: >>> >>> Nominal Level and Test Tones: >>> +6 dBU = 1,550 V = 0 dBr (VU) = -9 dBFS >>> >>> In the area of the Audio Engineers Society (AES) the following levels have >>> been agreed on: >>> >>> Nominal Levels and Text Tones: >>> +4 dBU = 1.228 V = 0 VU = -20 dBFS >>> >>> Why? >>> >>> EBU >>> +6 dBU was selected to produce a high signal/noise radio in a symmetric >>> line environment >>> -9 dBFS was selected because large digital headrooms are not a necessity in >>> a pre processed audio signal environment >>> 0 dBr is the 0 dB mark on a PPM >>> >>> AES >>> -20 dBFS was selected to provide enough digital headroom in a live signal >>> environment in order to protect the live recorded material from clipping in >>> a digital environment >>> >>> CD / DVD production >>> In the beginning of the digital audio age a CD was produced AAD (Analogue >>> Recording, Analogue Mastering, Digital Product): >>> The recording was made on a analogue multitrack recorder such as STUDER and >>> then mixed down in a studio on a 2 track tape (mainly with DOLBY SR or >>> TELCOM C noise reduction). >>> This tape was then processed in a PREMASTERING STUDIO. There this tape was >>> EQed and dynamically processed and then recorded on a U-MATIC digital Audio >>> Recorder with pq encoding. >>> The pq encoding was the track, subtrack and pause marks as well as the >>> index (Table Of Contents, TOC) of the CD. >>> As there was NO digital audio processing at that time it was a lot of work >>> to copy the analogue tape as the individual peaks had to be found out first >>> in oder to provide the maximum available dynamic range for the recording. >>> In addition there is an option called emphasis - this is some sort of noise >>> reduction in a digital environment. If you copy a CD digitally there might >>> be a change in the treble. That is caused by emphasis. The track would need >>> deemphasis. >>> Today digital audio processing is the daily business in the recording >>> industry and therefore the recordings appear much louder. The typical CD >>> shows a level of -0.2 dBFS. Theoretically 0 dBFS would be possible and some >>> unprofessional mastering guys provide premasters like that to the >>> manufacturing plants. But it makes sense to keep masters at -0.2 dBFS to >>> ensure there is no digital clipping. Some CD players actually cannot handle >>> 0 dbFS and produce clipping during playback. In addition a prolonged 0 dBFS >>> is considered a digital clip as it is unknown weather this really is a >>> clipping of a signal that normally would extend above the 0 dBFS or not... >>> >>> How to measure levels >>> A classical VU meter is not aligned to integration times - therefore it is >>> not suitable for a professional level measurement. >>> To measure a line audio level an integration time of 10ms has >>> internationally been agreed on >>> To measure a digital audio level the peak sample is what counts. So there >>> is no integration time, the measurement time frame equals the sampling rate. >>> For the fallback time a value of 1.7s (+/- 0.3s) / 20 dB is acceptable >>> The display range according to DIN 45406 / EBU / IEC 268-10 should be -50dB >>> to +9dB if used in an EBU environment >>> It makes sense to provide a peak hold function and to use at least 200 >>> segments for accurate readability. >>> RTW and other companies use different brightness values or additional bars >>> to display both the analogue and the digital integration time measurement >>> results and (in case of RTW) the calculated loudness at the same time. >>> However it appears to be a problem for most audio applications to provide >>> an accurate level display in their applications. >>> Maybe a programmer would like to implement the above values into the >>> RIVENDELL working environment. I would love it! In addition it would be >>> GREAT if the user would be able to adjust the system level of RIVENDELL >>> according to its working environment display wise. I am located in the EBU >>> area and I work with -9 dBFS for 0 dBr (VU). So sadly the built in >>> Rivendell level meters will always display an incorrect level. >>> >>> Cheers, >>> Chris. >> _______________________________________________ >> 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 -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.17 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAlAejx8ACgkQ22kkGnnJQAxRdQCdHtdYOR6shpHxvIq4VeqlOp2r C1sAnAyO4PfWgWVMt9C2gnvbolXPHGMz =NyMB -----END PGP SIGNATURE----- _______________________________________________ Rivendell-dev mailing list [email protected] http://lists.rivendellaudio.org/mailman/listinfo/rivendell-dev
