Inregistrari audio pe VCR

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LEKTOR
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Inregistrari audio pe VCR

Post by LEKTOR »

Are cineva experienta / experimente cu asa ceva ?

Eu am un JVC digital vHs mai vechi si am facut ceva inregistrari pe caseta video d-vhs si mi-a placut cum suna !

http://support.jvc.com/consumer/product ... chive=true" onclick="window.open(this.href);return false;

Alte VCR cu performante bune

- Panasonic AG 1980 - considerat top in s-vhs

http://www.vhsequipment.com/product_inf ... ucts_id=22" onclick="window.open(this.href);return false;

- JVC

http://support.jvc.com/consumer/product ... chive=true" onclick="window.open(this.href);return false;


ARTICOL INTERESANT - http://en.wikipedia.org/wiki/VHS#Audio_recording" onclick="window.open(this.href);return false;
... living a vi(ntage)king analog lifestyle in a digital world ...

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LEKTOR
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Re: Inregistrari audio pe VCR

Post by LEKTOR »

VCR AUDIO RECORDING

To get perfect reproduction, the FM subcarrier waveform being played back by one audio head must perfectly match the waveform from the other head at the point of head switching if a glitch is to be avoided. If you record and then play the tape on the same VCR under exactly the same conditions, you have a reasonable chance of this working. But if the tape stretches just a bit, or you play it on another VCR whose heads are not in exactly the same position, or the tracking is off, the waveforms will no longer match exactly, and you will get a glitch in the recovered waveform every time the heads switch. This sounds like a 60 Hz buzz in the audio, which is often audible through headphones even if not through speakers. The same glitch will occur in the video waveform too, but since head switching always happens during vertical retrace, you won't see it. Some VCRs have azimuth correctors or Dynamic Track Following which minimize these problems (Philips V2000 and some VHS). The wonderful signal to noise ratio of VHS HiFi is achieved through the use of compression before recording and expansion after playback. The actual signal to noise ratio of the tape itself is about 35 dB and a 2.5:1 compressor is used to "squeeze" things to fit. Like all companders, this produces audible errors at certain places on certain signals, such as noise "tails" immediately after the end of particularly loud passages. Worse, compressors often have problems simply getting levels right. That is, if you record a series of tones, starting at -90 dB and working up in 1 dB increments to 0 dB, and then play them back, you will almost invariably have level errors. The trend from soft to loud will be there but the steps won't be accurate. Two or three of your tones might come out at essentially the same level, then the next one takes a big jump to catch up or even overshoot. For music, the result will be that the relative levels of some instruments, passages, etc. will not be accurate. This doesn't matter as much for movies, which tend to have steady volume level. Also, movie enjoyment is rarely hurt by these level errors. VHS and Beta HiFi is fine for reproduction of movie and tv soundtracks. They are also perfectly fine for non-critical audio applications. But VHS and Beta HiFi are not serious competitors to DAT, CD, open-reel analog tape, or even a high quality cassette deck. 14.19 How do HiFi VCRs compare to cassette recorders? DAT recorders? VHS HiFi and Beta HiFi are analog recording formats which use modulation techniques to record a video signal and a stereo audio signal on a videocassette. The audio capabilities typically surpass that of the "linear" audio tracks found on all video recorders, thus the "HiFi" designation. "HiFi" is essential for getting good sound quality on your video recordings and out of pre-recorded videos. HiFi is also touted as an excellent audio recorder for audio-only (no picture) applications. Progress in HiFi has modern VHS HiFi equipment on par with the best analog cassette recorders and close to that of the digital formats. VHS HiFi suffers generational loss and noise, but because of the high quality of the AFM (HiFi) track, these generational losses are minimal and not as severe as those of audio cassettes. Many people use VHS HiFi for recording radio broadcasts, since VCRs often have built-in timers and can record for up to 9 hours. If you use a HiFi video recorder to record from an audio-only source, beware that some decks will not function properly without a video signal for synchronization. If you are interested in very good quality sound, use a deck with manual level control. 14.20 What is the difference between VHS HiFi and Beta HiFi? To record the video and HiFi sound signals onto the same tape area, VHS HiFi uses "depth multiplexing", while Beta HiFi uses "frequency multiplexing". That is, the FM signal for Beta HiFi occupies a different frequency band than do the Beta format's luminance and chroma signals, and is simply mixed with those signals and laid down on the tape by the video heads. In VHS the luminance and chroma signals were too close together in frequency for this to work. VHS HiFi uses a separate pair of heads on the spinning head drum to record the HiFi carrier. These heads' gaps are shaped so that the HiFi carrier is actually recorded at a different depth in the tape than the luminance and chroma signals.

Read more: http://www.faqs.org/faqs/AudioFAQ/part7/#ixzz0Zyz7b7O6" onclick="window.open(this.href);return false;
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Obelix
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Re: Inregistrari audio pe VCR

Post by Obelix »

Erau la moda la un moment dat niste adaptoare "HI-FI" care foloseau un VHS drept suport de inregistrare (nu stiu cum functionau, nici de ce nu s-au impus pe piata)
Am ascultat asta de vreo 2-3 ori, sunetul era de o calitate intre caseta si o banda buna pe "19"...

puf
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Re: Inregistrari audio pe VCR

Post by puf »

Am ascultat la sfarsitul anilor "80 multe astfel de casete VHS HI-FI trase numai audio.
Sunetul era grozav, bateau lejer deck-urile Akai foarte la moda pe vremea aia.
Ce imi placea in mod deosebit era faptul ca aveau zgomt de fond foarte mic iar pe vremea aia fisiitul era o obsesie.Inca ceva grozav era banda audio redata care nu suferea caderi la extreme cum apareau la diverse tipuri de benzi/casete audio sau la diverse azimutari.
Sunetul era dinamic, fara zgomot, inaltele si subbasul aveau energie dar parca ii lipsea caldura si finetea unui magnetofon bun.
Totusi trebuie precizat ca majoritatea casetelor VHS veneau din SUA gata inregistrate de la rude ale amicilor si nu stiu ce surse foloseau(posibil CD :) )

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momolo
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Re: Inregistrari audio pe VCR

Post by momolo »

puf
Sunetul era dinamic, fara zgomot, inaltele si subbasul aveau energie dar parca ii lipsea caldura si finetea unui magnetofon bun.
- fix aceeasi senzatie am avut-o si eu.

Am avut VHS-uri HIFI, chiar am cumparat o data un SONY cu 8 capete si inca doua JVC HiFi Stereo. La unele posturi de radio dupa 1990 se foloseau pentru a inregistra tot ce se emitea, era legal obligatoriu si aceste VHS HiFi aveau si LP, adica long play, jumatate din viteza si deci dublu la timp.

Pe SONY produs in 1990 l-am cumparat defect-varza, cu o poala de bani ca asa era pe atunci. Apoi am cumparat "pastile"" de cap rotativ, 8 la numar pentru ca intregul cap rotativ m-ar fi costat o avere si nu aveam bani. Apoi le-am schimbat cu mana mea si a durat vreo 3 zile pana sa-l reglez incet-incet, pastila cu pastila cu inbusul si oprit-play, oprit-play, etc,etc. Atunci am constatat ca daca nu era mecanica perfecta si capete aliniare PERFECT, se afecta sunetul pe modulatia HiFi.

Acest aparate au avut toate 2 cai de sunet, cel stereo HiFi modulat peste semnalul video pe capul rotativ si sunetul obisnuit pe capul ca de casetofon folosit de toate VHS-urile care nu erau HiFi. Diferenta de calitate era crunta, sunetul normal era ala pe care-l stim, sub cel mai prost casetofon (logic, viteza benzii era extrem de mica) insa cel HiFi stereo era de o calitate exceptionala.

Primele modele VHS HiFi aveau inregistrarea sunetului manuala ca la orice deck. Apoi au fost scoase cele cu inregistrare sunet automata, apoi cele fara Vumetre.

Cea mai buna marca era JVC. Am cumparat o data doua defecte, le-am facut bucati si din doua am facut unul ca nou. Sunau grozav insa asa cum am spus, alinierea capului rotativ (pastilelor) era critica precum si mecanica si calitatea casetei. La cel mai mic rateu se pierdea purtatoarea de sunet si HiFi-stereo fiind inlocuita de sunetul de la capul normal static de sunet, foarte suparator. La casete proaste sunetul se toca. Deci, sunetul stereo era mult mai sensibil decat semnalul video, trebuiau casete perfecte si bune, mecanica si capul in stare curate si perfect aliniate.

Stiu si cativa care trageau muzica inainte de 1989 si care foloseau VHS HiFi (JVC) ca master. Dar se plangeau de problema calitatii casetelor si a fiabilitatii reduse a benzii, adica in caz ca o rulai de multe ori se afecta calitatea stereo. Magurile erau mult mai fiabile dar si mai scumpe cu banda buna mai scumpa.

Unele modele VHS aveau functie de utilizare fara video, doar pentru sunet. Deci, partea buna era pretul la banda, mic, partea proasta, fiabilitatea redusa. Pe o caseta VHS incapea mult si deci era ieftina raportat la timpul de inregistrare.

In concluzie sunau grozav dar nu au prins din cauza fiabilitatii reduse si a faptului ca intre aparate (noi din fabrica) existau diferente de azimut care duceau la redare compromisa pe o caseta trasa pe alt aparat. Deci pe VHS-ul pe care trageai, pe ala redai.

Imi aduc aminte ce uimit am fost de calitatea acelui prim SONY HiFi cu 8 capete (evident, dupa ce l-am reparat; era lucrat minunat, inteligent, superb!), VHS care avea front rabatabil si jog mare.
Imi placea si imaginea.....dar astazi as rade de acea imagine ca de o gluma proasta!
"Tinereţea este o noţiune, biologia un adevăr. Ele împreună dau dimensiunea existenţei"(Geo Bogza)

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LEKTOR
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Re: Inregistrari audio pe VCR

Post by LEKTOR »

Se folosea caseta/banda S-VHS in deckuri speciale numai pt audio - era formatul ADAT dezvoltat de Alesis/Numark ( firma americana specializata in chestii pro - mixere,monitoare,etc ) - pe aceasta banda se tragea digital

http://en.wikipedia.org/wiki/ADAT" onclick="window.open(this.href);return false;
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LEKTOR
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Re: Inregistrari audio pe VCR

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Alte vcr / audio recordere mai bune

- SONY cu 6 capete - http://www.welectronics.com/VCR/SONY_SLV-ED949.html" onclick="window.open(this.href);return false;

- SHARP cu 8 capete 19 microni - VC-H98U - ar fi costat 10,000 $ la vremea lui !!!! - http://translate.google.com/translate?h ... start%3D10" onclick="window.open(this.href);return false;
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puf
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Re: Inregistrari audio pe VCR

Post by puf »

Eu am folosit intens VCR cu casete VHS hi-fi inainte de anul 2000 in special pentru faptul ca putea citi formatul surround din canalele stereo, format decodat de receiver multicanal Pro-logic.
Casetele originale din magazine aveau 90% sunetul surround si efectul multicanal din receiver si incinte era deosebit si imi placea mai mult decat primele generatii de Dolby-Digital dupa DVD redate de sisteme pocnitoare gen Pascal de la Sony.
Mai am si acum recorderul Panasonic NV-HD640 care are un mecanism grozav, super simplu, fara curele si angrenaje complicate si care este revolutionar fata de primele generatii de recordere VHS.
Nu am timp si chef ca as face unele teste de inregistrare dar imi este teama ca treaba cu problemele legate de banda, caseta pot ruina din cand in cand, uneori excesiv de des, inregistrarea.Banda este foarte sensibila si in general sufera diverse deformari, uneori chiar datorita manipularii automatice din interiorul recorderului, si pot apare "bube" din loc in loc.Din cate mai retin chiar si casetele originale noi mai aveau glitch-uri uneori.

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momolo
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Re: Inregistrari audio pe VCR

Post by momolo »

puf
Din cate mai retin chiar si casetele originale noi mai aveau glitch-uri uneori.
exact! Chiar si TDK sau Maxell mai aveau bube, insa nu cele de top care oricum nu ajungeau la noi si costau mult (nu degeaba). Dar pe imagine nu era problema mare, nici nu ne pasa, eu am vazut oameni care se uitau la filme trase verde-rosu cu imaginea care se dadea des peste cap din nesicronizare ....si care isi pusesera :roll: ....ochelari de soare! :shock: :lol: Traducerea, defapt dublarea filmelor trase "minunat" (copia copiei copiei pe casete proaste) era facuta de celebra Irina Nistor. Ce vremuri!
"Tinereţea este o noţiune, biologia un adevăr. Ele împreună dau dimensiunea existenţei"(Geo Bogza)

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LEKTOR
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Re: Inregistrari audio pe VCR

Post by LEKTOR »

Partea audio era trasa pe o margin f. ingusta a benzii, margine care usor era sifonata - se mai foloseau si derulatoare de casete dedicate !

A avut cineva experienta cu ADAT mentionat mai sus ?
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momolo
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Re: Inregistrari audio pe VCR

Post by momolo »

Partea audio era trasa pe o margin f. ingusta a benzii, margine care usor era sifonata - se mai foloseau si derulatoare de casete dedicate !
capetele ca de casetofon pentru sunetul normal erau pe partea de jos a benzii VHS si aveau daca nu ma insel latimea intrefier cat a unui casetofon obisnuit. Existau si unele VHS care erau stereo pe acest cap fix, adica in spatiul destinat existau doua bobine cu intrefier ca la un casetofon stereo. Sunetul era stereo dar prost.
A avut cineva experienta cu ADAT mentionat mai sus ?
- cred ca niste amici stiau despre ce era vorba fiind in domeniul profy. Eu nu am vazut/auzit decat formatul DAT.
"Tinereţea este o noţiune, biologia un adevăr. Ele împreună dau dimensiunea existenţei"(Geo Bogza)

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