1、= 3404583 0063395 420 EUROPEAN STANDARD EN 61120-1 NORME EUROPENNE EUROPISCHE NORM April 1993 UDC 621.396.7 : 681.84.083.84 : 681.327.636 Descriptors: Audio recording, stereophonic sound, digital signal, magnetic tape, audio tape recorder, mechanical characteristics, electrical characteristics, enco
2、ding, recording tracks, interchangeability English version Digital audio tape recorder reel to reel system, using 6,3 mm magnetic tape, for professional use Part 1 : General requirements (IEC 1120-1 : 1991) Systme denregistrement bande Digitales lbnbandgert audionumrique, bobine bobine, utilisant Sp
3、ulensystem mit Magnetband 6,3 mm fr une bande magntique de 6,3 mm, usage Studioanwendungen professionnel Eil 1 : Allgemeines Partie 1 : Gnralits (IEC 1120-1 1991) (CE1 1120-1 : 1991) This European Standard was approved by CENELEC on 1993-03-09. CENELEC members are bound to comply with the CENICENELE
4、C Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN
5、ELEC member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions
6、. CENELEC members are the national electrotechnical committees of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CENELEC European Committee for Electrotechnical Standardiz
7、ation Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B- 1050 Brussels O 1993 Copyright reserved to CENELEC members Ref. No. EN 61120-1 : 1993 E Page 2 EN 61120-1 : 1993 Foreword The CENELEC questionnaire proce
8、dure, performed for finding out whether or not the international Standard IEC 1120-1 : 1991 could be accepted without textual changes, has shown that no common modifications were necessary for the acceptance as European Standard. The reference document was submitted to the CENELEC members for formal
9、 vote and was approved by CENELEC as EN 61120-1 on 9 March 1993. The following dates were fixed: - latest date of publication of an identical national standard (dop) 1994-03-01 - latest date of withdrawal of conflicting national standards (dow) 1994-03-01 Annexes designated normative are part of the
10、 body of the standard. In this standard, annex ZA is normative. 3404583 0063397 ZT3 W Page 3 EN 61120-1 : 1993 CONTENTS 1 2 3 4 5 6 7 8 9 10 11 12 scape Normative references Definrtionc . 3.1 Digital encoding . . . 4.1 Sampling frequency . 4.2 Sampling timing 4.3 Quantization Tape speed . Tape windi
11、ng Reel and hub Allocation and dimension of magnetic tracks Assignment and dimension of magnetic tracks Emphasis Auxiliary channels . . Data flow of a digital audi tape recorder 11.1 11.2 11.3 11.4 Time code channel (sub-track i) . 1 1.1.1 Time code reoording . 11.1.2 Recording method . Auxiliary da
12、ta channel (sub-track 2) . 1 1.2.1 Recording method .- . Auxiliary channels (subtracks 3 and 4) ._ 11.3.1 Auxiliary channels for format A .- 11.3.2 Auxiliary channels for fonnat B . Alignment . Identification . 12.1 Fmat idenafication Annex ZA (normative) Other international publications quoted in t
13、his standard with the references of the relevant European publications . 4 4 4 5 7 7 7 7 8 8 8 8 8 10 10 10 10 10 10 10 11 11 11 11 11 11 12 = 3404583 0063198 L3T Page 4 EN 61120-1 : 1993 DIGITAL AUDIO TAPE RECORDER REEL TO REEL SYSTEM, USING 6,3 mm MAGNETIC TAPE, FOR PROFESSIONAL USE Part 1 : Gener
14、al requirements 1 Scope This part of IEC 1120 applies to stereophonic digital audio recording on 6,3 mm wide tape with stationary heads for professional use. It defines the mechanical and electrical charac- teristics necessary to ensure the interchangeability of programme recorded digital audio sign
15、al on magnetic tape amongst professional industries. This standard is presented in three parts. Parts 2 and 3 describe two formats usable within part 1. It Is practical to have switchable operation between these two formats. Conse- quently it is logical to include both in one standard. 2 Normative r
16、eferences The following standards contaln provisions which, through reference in this text, constitute provisions of thls part of IEC 1120. At the time of publication, the editions Indicated were valid. All standards are subject to revision, and parties to agreements based on this part of IEC 1120 a
17、re encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and IS0 maintain registers of currently valid International StandardS. IEC 94, Magrtetic tape sound recording and reproducing systems. IEC 268-1 2: 1987, Sound system eq
18、uipment - Part 12: Application of connectors for broad- cast and similar use. IEC 268-15: 1987, Sound system equipment - Part 15: Preferred matching ValUeS for inter- connection of sound system covonents. IEC 461 : 1986, Time and control code for video tape recordem. IEC 899: 1987, Sampiing rate and
19、 soutee encoding for professionai digitai audio recording. 3 Deffnltlons For the purpose of this part of IEC 1120, the following definitions apply. = 3404583 00b3L 07b cn Analogue Page 5 EN 61120-1 : 1993 Reud head Decoder + amplifier DIA converter 3.1 Figure 1 shows within a block diagram the main
20、data flow of a DATR (digital audio tape recorder). Data flow of a digital audio tape recorder Figure 2 shows the recording channels of a DATR. Figure 3 shows the reproducing channels of a DATR. Audio channel 1 = lef channel (L). Audio channel 2 = right channel (R). Analogue r i Encoder Modulator con
21、verter t I Digital interface IEC standard professional use Digital output amplifier + head - Figure 1 - Data flow of the main audio channels of a DATR 3404583 00b3200 bL8 = Modulator 4 and write amplHior Page 6 EN 61120-1 : 1993 -8 2 -1 Digital audio input interface b * Ch 1 ,a Auxiliary channds for
22、 audio cueing and/or data modulator AnaIqEl converter Time code O + Digital audio processing Time codo channel modulator *i Main tracks Ch 2 r I Auxiliary data channel modulator Figure 2 - Recording channels of a DATR D 3404583 O063203 554 D 81- 2+ 1- Page 7 EN 61120-1 : 1993 I Demodulator Digital r
23、ead - audio amplifier processing Main 4- 3 b Auxiliary channels for audio cueing andlor data demodulator II O Chl 0 Ch2 Auxiliary data 3 Auxiliary data channel demodulator Digital audio output Interiace Auxiliary data o Ch 1 1 b 4 coztrter 1-0 Analogue audio Time code Time code channel demodulator O
24、 L I Ch 2 Figure 3 - Reproducing channels of a DATR 4 Dlgltai encoding 4.1 Sampling frequency The sampling frequency shall be 48 kHz, and the accuracy of the sampling frequency at encoding shall be f50 ppm. 4.2 Sampling timing It is recommended that two channels are sampled simultaneously. 4.3 uanti
25、zation Each audio sample shall be quantized uniformly and be expressed in 16 bits, 2s comp- lement code, and MSB leading shall be used. 3404583 00b3202 490 Page 8 EN 61120-1 : 1993 5 Tapespeed The tape speed shall be nominal 38,l cms (hereafter called speed I) and 19,05 cm/s (hereafter called speed
26、Il). The tolerance on tape speeds shall be within 0,2 %. 6 Tape winding The magnetic coating faces the centre of the reel. 7 Reeland hub Under consideration. 8 Allocation and dimension of magnetic tracks Figure 4 shows the track allocation on magnetic tape. 9 Asslgnment and dimension of magnetic tra
27、cks Under normal operation, the designation of magnetic tracks is as follows: If the tape moves from left to right with the magnetic coating facing away from the observer and with the leader to the right, the top track is designated sub-track 4, the next lower track is designated sub-track 3 and so
28、on. Track assignment Track Format A Format B 3-10 MAINTRACK 1 to8 DA DA 1 SUB-TRACK 1 TC TC 2 SUB-TRACK 2 AUX-D PRT 12 SUB-TRACK 4 CUE-CH2 CUE-CH1 CUE-CH1 and2 11 SUB-TRACK 3 CUE-CH1 CUE-CH2 AUX-D DA: Two digital audio channels TC: Time code channel RT: Reference Track AUX-D: Auxiliary data channel
29、CUE-CH1 : Cue audio 1 CUE-CH2 Cue audio 2 3404583 O063203 327 Page 9 EN 61120-1 : 1993 O I Figure 4 - Track pattern for DATR on 6,3 mm magnetic tape 3909583 0063209 2b3 m Page 10 EN 61120-1 : 1993 10 Emphasls In general the use of emphasis is not recommended. If pre-emphasis is applied, it is identi
30、fied on the tape, and the emphasis shall be used with the characteristics of a first order pre-emphasis as shown below. m U 8 n a !?! c O r, e t B -I +16 Pie-emphasis +6 d0l oct +O i -1 o -6 dBt OCt -1 I I I 1 20 K I#: nu91 4K 8K Frequency Hz 1K 2K 11 Auxiliary channels The two formats allow the rec
31、ording of four auxiliary channels on sub-tracks. 1 1.1 One time code channel unsynchronized to digital audio is provided. 1 1.1.1 Time code recording The time code according to IEC 461 is recorded in the longitudinal direction of the tape. 1 1.1.2 Recording method Time code channel Is recorded on ta
32、pe by the direct recording method. Time code channel (sub-track 1 ) 11.2 Auxiliary data channel (sub-track 2) The auxiliary data channel may be used for the recording of user information (format A) or reference track slgnal (format 6). 1 1.2.1 Recording method Auxlliary data channel Is recorded on t
33、ape by the direct recording method. m 3404583 00b3205 LTT m Page 11 EN 61120-1 : 1993 11.3 Auxiliary channels (sub-track, 3 and 4) 1 1.3.1 Two independent cue audio signals are recorded by PWM modulation on the tape and contain the same audio information as digital audio channels. Auxiliary channels
34、 for format A 1 1.3.2 Auxiliary channels for format B The cue audio signais are recorded analogue (direct) or with PWM modulation. For auxiliary data on sub-track 3, they are recorded by the direct recording method. If auxiliary data recording is used, a monophonic cue audio signal is recorded on su
35、b-track 4. 11.4 Alignment The relative location of recording for four auxiliary channels with the digital audio channels on the tape shall be specified for compatibility. The alignment tolerance is defined in 2.2 of parts 2 and 3 of this standard. 12 Identification 12.1 Format identification The ide
36、ntification format shall consist of unit frames and unassigned address bit No. 58 in time and control code for video tape recommended by IEC 461. Identification data assignment Unit of frames 0000 000 1 001 o 001 1 o1 O0 o1 o1 O110 o111 1 O00 1 O01 Unassigned address bit No. 58 O 1 1 1 1 1 1 1 1 1 f
37、ormat Not used Write protection Format A identification Format B identification Reserved for format identification Reserved for format identification Reserved Reserved Reserved Reserved rn 3404583 O063206 036 rn Page 12 EN 61120-1 : 1993 Annex ZA (normative) Other international publications quoted i
38、n this standard with the references of the relevant European publications When the international publication has been modified by CENELEC common modifications, indicated by (mod), the relevant EN/HD applies. IEC publication Date Titie 94 series Magnetic tape sound recording and reproducing systems S
39、ound system equipment 268- 12 1987 Part 12 : Application of connectors for broadcast and similar use 268-15 1987 Part 16 : Preferred matching values for the interconnection of sound system components 46 1 1986 Time and control code for video tape recorders 899 1987 Sampling rate and source encoding for professional digital audio recording EN/HD HD 311 HD 483.12 S2* HD 483.15 S4* HD 507 S1 Date series 1993 1992 1988 - * HD 483.12 S2 includes Al : 1991 to IEC 268-12 HD 483.15 S4 includes Al : 1989 + A2 : 1990 + A3 : 1991 to IEC 268-15
