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Analog sound recording to videotape

Digital recording of sound is popular because of digital sound editors and digital audio workstations. But some want to use analog sound, so they record to analog tape. But analog tape does not offer nonlinear editing capabilities like digital DAW. Analog audio can be stored in videotape, like VHS. Hi-fi VHS cassettes can store audio at 90db dynamic range, CD quality, with video also. Earlier videocassettes were used in nonlinear film editing, systems like Ediflex and Montage (and there were more, less known) had 12 or 18 videocassettes and controlling system for film editing. Similar “virtual Ediflex” in software, that uses computer software to control 6 - 12 VHS hifi cassette players (VHS players have been manufactured until lately) but they don t record picture, but sound. Its like Ediflex nonlinear film editing for analog sound. Also video of VHS can be used to store one or more analog channel of sound. Audio was encoded for videocassettes in AFM, audio frequency modulation. Video uses less than 2 X bandwith when PAL or NTSC TV system is used. They have 5,5 - 6 mhz bandwith with 3,6 - 4,2 mhz “real” bandwith. If audio of 20 khz uses 40 khz bandwith, and 60-64 audio channels are grouped in videotape in 40 khz + 40 khz + 40 khz etc configuration, 2,4-2,56 mhz is needed. if 20 audio khz uses 60 khz channel (or 18 khz uses 60 khz channel) about 3,6 mhz is needed which is NTSC videotape frequency. So 60 audio channels + 2 VHS hifi channels fit in VHS cassette. High quality S-VHS, SP Betamax etc video can be used. If only 1 X audio to video and 2 X VHS hifi channels are used that is 3 X audio channels in one cassette, system has 6 - 12 VCR players so 18 to 36 audio channels. Also open reel 1 inch type C videotape can be used to store sound only, it has high quality. Analog HDTV like Sony Hi-Vision or MUSE TV (W-VHS) can store high quality analog audio in videotape, recording analog audio only, not video. If video is needed for stabilisation purposes blank black picture that is embedded in audio information like hifi audio is embedded in video information can be used. VHS hifi uses “depth embedded” technique to store audio information in video picture. Same can be used vice versa, videotape is used to store analog audio, many channels, and one embedded video channel in audio information also that shows black picture for tape stabilisation if needed. There are different picture into sound or sound into colour conversion programs (Audio Paint etc). Slow scan TV is one example. So sound can be converted to video picture and then stored as PAL, NTSC or MUSE video. Quadrature Amplitude Modulation can be used in analog QAM format, for example QAM 64 analog, to store 64 audio channels in video picture using shapes and colour for audio frequency equivalent. High quality video like SP Betamax, S-VHS, U-Matic, 1 inch open reel videotape, or analog HDTV (MUSE, Hi-Vision) can be used to store audio information and video only as stabilisation if needed. Or audio is encoded in multritrack QAM format in video picture itself. Or using other way to encode sound into moving picture. Additional audio tracks like VHS hifi can be used. VHS has also mono or stereo (not hifi quality) linear audio tracks, those can be used also altough they are not good quality. Videotape speed can be speeded up so that analog multitrck sound encoded in video picture gets better, if videocassettes are used for sound recording. In open reel videotape quality is not a problem. For vinyl LP CD quality can be reached if noise reduction like High Com (or other) is used in vinyl LP, and then computer software program that monitors analog output from record player is used and it corrects sound to normal by controlling analog amplifier that is connected to record player. So High Com (or other) codec is not needed in hardware, it can be in software also, and it controls amplifier by monitoring analog output from record player. Ordinary C-cassettes can be released with many noise reduction formats, so for example album can be released in cassette form using Dolby B, C, or S, so three different versions of cassette for one album. Or all three (B,C and S) can be in one casette, album is in three versions in one cassette. Also speeded up cassette speed that improves sound quality can be used in cassettes, cassette decks have sometimes possibility to double cassette speed. Album can be stored as normal speed Dolby B and then speeded up Dolby C for good quality in one cassette, Dolby B plays in normal low quality cassette player, speeded up Dolby C in high quality hifi deck. Or cassettes can be released without Dolby because cheap cassette players have no Dolby. That makes four different versions of one album in cassette. Vinyl LPs can be released in 78 rpm versions, because many record players have 78 rpm option, altough playing time per LP side is short, so double LPs or even triple LPs per album are needed. 45 rpm LP pressings can be used also (and are also used today). Direct metal mastering for LPs can be used. Releasing music albums as VHS hifi cassettes can be used, they have (almost) CD quality sound and music videos can be put in VHS cassette with analog hifi sound also in music albums released as videocassette, or using black TV page when just music is played. High quality analog sound in VHS, competing CD quality, so music album in VHS cassette can be sold instead of vinyl LP or cassette to analog enthusiastists, and VHS has much higher analog sound quality (VHS hifi) compared to cassette or LP. Also old Laserdisc (LaserVision) players can be used to analog sound distribution. No laserdiscs are manufactured, but for example laserdisc CD video (has only 5 minutes of play time per side) or magneto - optic 5,25 inch disc not as magneto - optic but cheap CDR type organic layer disc that has laserdisc information in both sides. Playing time is about 40% longer than laserdisc CDV, so 7 minutes per side. If only sound is stored in laserdisc only 2,8 mhz is needed which is half of 5,5 mhz laserdisc video. So 14 minutes per side or 10 minutes if normal 4,7 inch / 120 mm disc is used. Laserdisc “extented play” mode can be used to store little more playing time but not much, and in selected players (?) only. In lower frequencies video information for stabilisation can be used. So 5,25 inch disc in laserdisc form can be used to store analog audio (and video also). Albums need multiple discs because of short playing time. So good quality analog music can be released in many formats, in open reel tapes like 2 or 4 track or even 8 track also (again). Music album uses 2 tracks (or 4 tracks if quadrophonic) so 2 track album uses very little amount of tape when put to 8 track reel because it uses 4 X 2 tracks of tape (tape must be turned 4 times during playback). Blu ray discs that are rewritable Bluray RW type, can be used to store laserdisc style encoding in analog form, so it will be like Laserdisc analog sound in Bluray disc, but no one has done it yet. It would have good analog quality and if multiple layer Bluray discs are used also long playing time with good analog sound quality. Slightly modification for Bluray writer is needed, and some form of error correction to Laserdisc encoding. Or some other way to encode analog audio to Bluray discs. Decoding must use analog electronics so that it is analog sound, not digital. Some Pioneer Laserdisc players had 98, 102 and 115 decibel dynamic range in audio output, and that was perhaps for analog sound, so Laserdisc can have good quality analog sound also not just VHS hifi. Using mechanical parts of Bluray RW player but changing all digital parts to analog electronics and using similar pulse width modulation encoding like Laserdisc or some other analog encoding method is possible to make analog Bluray that can be used in sound recording and playback. Encoding and decoding must use analog electronics. Analog form of error correction must be used, that uses delay lines like analog TV systems? Or closing analog Bluray disc inside protective cassette that some car CD-players did. Using multilayer Bluray discs high quality and long playing time is possible. Releasing music albums as VHS hifi videocassettes (with perhaps only black TV picture when music is played) is simplest solution for CD quality analog sound. Those who want analog tape sound (tape saturation etc), 2-track reel to reel recorders that are grouped for example groups of 16 + 4 recorders, 16 X 2-tracks are for 32 track multirack recording and 4 X 2-tracks for 8 track mixdown. Those 20 2-track open reel recorders are computer controlled so nonlinear editing is possible. Its like Ediflex video editing again but done by 2-track reel to reel sound recorders and for sound not film. Editing similar like digital domain is now possible for analog tape recorders. Noise reduction can be done in computer software for all 20 recorders perhaps. Computer monitors sound input in 20 recorders (40 tracks) simultaneusly and uses software defined noise shaping, Dolby S, SR, DBX or High Com in software form (not in hardware) and adjusts analog sound using analog circuits accordingly. Because tape noise reduction is in software, not hardware, noise shapers can be many diffrent and user can choose by clicking if he uses Dolby S, SR, High Com etc. If noise reduction cannot be in software it must be in hardware. Analog pre-amplifires can be used in conjuction with tape recorders, and those amplifiers connected to computer that does noise reduction and adjusts analog amplifiers accordingly. In eastern Europe was 2-track reel to reel manufacturer, that was in 2010s last 2-track reel to reel recorder maker, but now high-end / expensive open reel recorders are again made. Videotape is another option for analog sound. S-VHS has S-video so it has 2 channel output, that can be used in 2 channel audio recording (and 2 VHS hifi channels, and 1-2 linear audio channels of VHS also). Scart connector has RGBY 4-channel output, so professional videotape equipment can be used in 4 channel audio recording. Or audio can be coded in analog video picture itself using quadrature amplitude modulation etc. Or divide frequencies of video picture to about 100 khz - 20 khz blocks and encode sound to those blocks. Up to 60 or more audio channels then fit in video picture stream. C-cassette based systems like Onde Magnetique, Tapetronic by Alexis Malbert, Scrubboard by Jeremy Bell, Melloman by Mike Walters, Sony Mellotron by Luke Randall are Mellotron style musical instruments. Using computer control and instead of Mellotron imitation those C- cassette systems can be used to analog sound recording, using nonlinear editing like digital sound recording. In netpage Yehar (Olli Niemitalo) is Rotolaserator, modernised Optigan style instrument. Simple Optigan style writing to disc with analog electronics and using multilayer Bluray disc can perhaps offer analog recording and playback with simple analog electronics. Those variable speed C- cassette Mellotron systems could be used in analog synth keyboards, if they had C- cassette station analog synth sound can be recorded and then manipulated like digital synths do, time-strecthing, pitch shifting etc. sound effects with analog sound done completely in analog form, and in keyboard itself with their inbuild C- cassette station or Mellotron type tape system. Altough C- cassette sound is not so good, using noise reduction and high tape speed in cassette can improve sound quality. So those analog synths would be analog synth / Mellotron hybrids. Analog tape unit as modular synth module is possible also, or as rackmount unit (it is done already, “CV Tape Player” by Xavier Gazon). Sound recording using multiple recorders / players that use videocassettes, open reel analog tape, or C-cassettes, with analog sound but digital timecode, accurate editing done by computer is possible, and nonlinear sound editing like digital audio workstations. United Home Audio makes reel to reel recorders that use “silver wiring” in internal connections that improves sound quality. Using silver wiring in videotape recorders that record for example 1 inch open reel or MUSE HDTV system, not video recording but audio sound to videotape, sound quality that is already high when recorded in videotape can be improved still. If digital sound must be used, and it must be compressed, perhaps good compression format is such that if 48 khz / 16 bit sound is compressed, 0-16 khz is using FLAC lossless compression, 16 - 36 khz Opus or other lossy format, and 48 - 36 khz sub band replication / high frequency replication. Actual sampling rate is 36 khz, it needs about 9 % for quantization noise, so 18 khz sound minus 9% is 16,4 khz about, over it is just sub band replication to 20 khz. SBR can use some “cue” information over 16,4 khz if needed in high frequencies. Highest musical notes possible are about 7 khz, so 6912 hz for lossless, from 6,9 khz to 18 khz lossy and above it SBR (quantization noise makes 16,4 khz highest sound for lossy altough sampling rate is 36 khz for 18 khz sound, so over 16,4 khz is SBR only). 6912 hz is easily divided to 32 (bits), and 6,9 khz is about one 3,5th of 24 khz range, so 1: 3,5 of frequency range is lossless (FLAC, Optimfrog etc.) which needs lots of bits, and rest lossy or SBR. Maybe that is economical bitrate digital sound that has good quality and is partially lossless and partially lossy. XiFEO FLAC and MQA (FLAC) compression can be used. Adding dithered noise shaping to FLAC file can make 8 bit PCM to about 16 bit dynamic range but it adds only 2% to FLAC file. Video players often have 4 tape heads in their tape head cylinder, and video signal when coming out from SCART connector has RGBY output for colours so 4 different signals. 4 tape heads X 4 signals is 16 signals. Those 16 signals can then be used for 16 track sound recording? Also 2 track VHS Hifi audio tracks are used, and 2 linear audio tracks (or just 1), so 20 track multitrack sound recording from one VHS video player / recorder is possible? That would be much cheaper than 16 or 24 track analog tape recorder, that can cost 10 000 dollars or more, and they all are used and worn already. And sound quality is also better than ordinary tape recorder, but not in 2 linear audio tracks of VHS that are very bad quality. So VHS cassette player / recorder offers unsurpassed sound quality with minimal price (compared to “real” tape recorders). When multiple videotape recorders are grouped together, even only 2 VHS Hifi tracks per VHS player is enough for 8 or 16 track recording (needs 4 and 8 VHS players, they have also extra 1 or 2 linear sound tracks that can be used in bad quality so 12-16 and 24-32 track recording is possible from 4 and 8 VHS players). This is without any modification of VHS player? Modified VHS player can use video signal also for sound recording. Normal VHS video output only has 2 colour / brightness values, using them and 4 tape heads is 8 signal sound recording for one videocassette, plus 2 VHS Hifi channels and 2 linear audio channels.