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One small mistake I must correct. DATcould be mass produced. Part of the 
DAT standard included a higher speed oxide tape based cassette that 
could play for 80 minutes instead of 120. These tapes could be 
replicated on high speed touch transfer system using the Currie point 
temperature for magnetic information transfer, like the later video 
systems. There were actually a few DAT cassette in the classical market. 
On a  side note, I wonder who was the "brain" that thought consumers 
would actually use all the id's and options on these machines. 70% of 
Americans at that time didn't even know how to set the VCR clock. That's 
why the barcode on TV guide was invented.
Shai

Tom Fine wrote:
> When DAT first came out, the original press on it was "here's a 
> cassette-like home medium for the digital age." But the 
> copy-protection scheme made it impossible to use it as many people 
> were using cassettes at that point (tape-to-tape copies), duplication 
> of DATs was a costly endeavor since they can't be run off on a 
> mass-duper like cassettes.  Remember that at that time period -- the 
> Walkman era -- cassettes were the primary mass medium for music in the 
> US, having passed LP numbers in the late 80's. So a cassette 
> replacement needed to have a major pre-recorded component. The record 
> companies had invested or were investing billions in CD plants, that's 
> what they wanted to be the _ONLY_ consumer mass-medium. So it was 
> another case of clever hardware engineering for a market that wouldn't 
> buy in quantity. BUT, DAT was immediately and enthusiastically 
> embraced by the portable-recording market, specifically higher-end 
> radio recording, recording of events at colleges and other venues, and 
> the Grateful Dead taping army, among other audiences. So, quickly, 
> quantities of recorded DAT tapes started piling up in various 
> organized and non-organized archives. Also at that time, 
> recording-industry people realized DAT was a good way to make a 
> listening/proof copy off the same digital buss feeding the 
> U-Matic-based mastering system. After all, any producer or record 
> company exec could have a DAT machine in their home or office, but few 
> to none could have a 1630 playback system. So more DAT tapes started 
> piling up. Then, lower-end studios and self-recording folks adopted 
> DAT due to convenience and cost. Many more small studios than we'd 
> like to think were mastering to DAT throughout the 90's and even into 
> this decade. Also the commercial/industrial sound production business. 
> And sound-for-picture.
>
> So, yes, never intended for the professional uses which became its 
> market.
>
> -- Tom Fine
>
> ----- Original Message ----- From: "Ted Kendall" 
> <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Thursday, January 21, 2010 6:05 AM
> Subject: Re: [ARSCLIST] DAT ripping
>
>
>> As far as I know, DAT was never intended as a professional medium at 
>> all, but a domestic one. The anti-copying furore in the US which led 
>> to SCMS scuppered that, so the Japanese had to sell it as an F1 
>> replacement.
>>
>> Agreed, though - those first generation machines can be very tolerant 
>> of marginal tapes. Whether this is a mechanical thing or more 
>> generous interpolation, I wouldn't know. I also harbour memories of a 
>> particular DAT which refused to play at all on any machine except a 
>> Fostex D20 - and that had the error light continuously on! The audio, 
>> however, was quite OK.
>>
>>
>> ----- Original Message ----- From: "Paul G Turney" <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Thursday, January 21, 2010 9:18 AM
>> Subject: Re: [ARSCLIST] DAT ripping
>>
>>
>> Further to this, you will find that some mechanisms perform better 
>> than others, the PCM 2500 for example will play tapes that the 7000 
>> series won't.
>> And often more plays will yeild a better file, but DAT was always 
>> meant to be an editing medium, not long term storage.
>>
>> Paul Turney
>> Sirensound Digital Audio
>>
>>
>> -----Original Message-----
>> From: Shai Drori [mailto:[log in to unmask]]
>> Sent: Thursday, January 21, 2010 09:14 AM
>> To: [log in to unmask]
>> Subject: Re: [ARSCLIST] DAT ripping
>>
>> Okay, that I understand, but I am thinking about correctable errors. 
>> We are then assuming that both systems will correct the errors the 
>> same way since both use the schemes implemented. How do we know which 
>> system has fewer errors over the other? My experience with rotary 
>> head systems is that sometimes second or third reading yielded better 
>> results, I think due to "cleaning" actions of the previous playing. 
>> Maybe we should compare five readings of the same cassette?ShaiTed 
>> Kendall wrote:> In my view, yes.>> Consider - you have two data 
>> files. One is a text document (for the > sake of argument). The other 
>> is a digital audio file. Both have errors > in the storage medium. 
>> This is inevitable, so we devise error > correction strategies 
>> (redundancy, check codes, etc). These allow us > to correct errors 
>> completely and accurately.>> Suppose now that there is an error in 
>> the storage medium which is too > large to be corrected. This will 
>> cause an obvious error in the text > file, which is unaceptable, so 
>> the system does not allow for it and > declares the file corrupt. The 
>> audio file, however, can be rendered > inoffensive by interpolation, 
>> and this is implemented in the DAT audio > format. If we retrieve DAT 
>> audio in a system which does not admit of > interpolation, we 
>> therefore know that the data are accurate, as any > uncorrectable 
>> errors are recorded as such.>>>> ----- Original Message ----- From: 
>> "Shai Drori" > To: > Sent: Thursday, January 21, 2010 7:37 AM> 
>> Subject: Re: [ARSCLIST] DAT ripping>>>> My own experience with dat is 
>> that almost all tapes have some form of >> errors on them. I think 
>> the idea in dds is that errors are better >> fixed than dat machines. 
>> There were many machines that came off >> assembly lines not at spec, 
>> thus making the tape not a standard tape. >> Some machines are better 
>> at coping with these (my experience with >> Sony is better than 
>> tascam for example, but I suspect this is highly  >> subjective). All 
>> in all, I think the DAT format was the word digital >> format I have 
>> ever come across.>> Also' checking two files one against the other 
>> will not necessarily >> prove one format better than the other. If 
>> you get some audio, how >> can you be sure one stream is correct and 
>> the other is corrupt? >> Either the dat or dds stream could be 
>> better, or am I missing >> something in the methodology?>> Shai>>>> 
>> Tom Fine wrote:>>> I'm happy to do a SPDIF to hard drive transfer and 
>> then exchange
>> >>> tapes with someone using a PC-drive transfer system so we can do 
>> the >>>
>> comparison Richard mentions.>>>>>> Please ping me off-list if you 
>> have a working PC-drive transfer  >>> chain and want to exchange DATs 
>> and computer files.>>>>>> -- Tom Fine>>>>>> ----- Original Message 
>> ----- From: "Richard L. Hess" >>> >>> To: >>> Sent: Wednesday, 
>> January 20, 2010 5:14 PM>>> Subject: Re: [ARSCLIST] DAT 
>> ripping>>>>>>>>>> Hi, Tom,>>>>>>>> After I saw your post and re-read 
>> Jim's post, I think I understand >>>> where he is coming 
>> from.>>>>>>>> What we _should_ be able to do is take the DDS ripped 
>> file and an >>>> AES/SPDIF'd copy of the DAT from an audio DAT 
>> machine, align the >>>> starts, invert the phase of one, and get 
>> dither or silence.>>>>>>>> In both instances, we're pulling numbers 
>> off the tapes (although >>>> the basest representation of the numbers 
>> is analog on the tape, the >>>> processing in both instances 
>> interprets these analog signals as >>>> either ones or 
>> zeros).>>>>>>>> I would not, without doing the tests that Jim is 
>> talking about, be >>>> 100.0000% confident that the two files are 
>> identical.>>>>>>>> I think that the DDS reading could be "better" 
>> than the audio DAT >>>> reading as there is no error concealment 
>> stage in a data recorder, >>>> so if you grabbed all the bits via the 
>> DDS route, you could be sure  >>>> that they were correct.>>>>>>>> 
>> These are all subtle differences and are probably not as large as 
>> >>>> the "Interstitial Errors" that Chris Lacinak is talking about 
>> here:>>>> 
>> http://www.avpreserve.com/wp-content/uploads/2010/01/Digital_Audio_Interstitial_Errors.pdf 
>>
>> >>>>>>>>>>>> I would expect some burst differences between the two 
>> methods,
>> and >>>> those bursts would be where the audio DAT's error 
>> concealment >>>> kicked in. Other than that, they should be 
>> identical, presuming you >>>> haven't introduced an interstitial 
>> error in one copy or the other.>>>>>>>> I'm glad to see Chris 
>> offering to help. I am interested in this. I >>>> would also like to 
>> know who is set up with the DDS Mass Ingest of >>>> DATs as I am 
>> sometimes asked who can do large DAT collections. At >>>> the moment, 
>> I am not interested in doing any because of anticipated >>>> 
>> remaining headlife on my machines, the growing lack of parts for >>>> 
>> DAT machines, the need to transfer my own DAT collection first, and 
>> >>>> the analog work that I have piling up.>>>>>>>> Cheers,>>>>>>>> 
>> Richard>>>>>>>> At 04:27 PM 2010-01-20, Tom Fine wrote:>>>>> Hi 
>> Jim:>>>>>>>>>> How could the data be "better" than a direct-digital 
>> out from a  >>>>> properly-working player (ie no head problems or 
>> mechanical >>>>> issues)? I thought the main advantage of the 
>> computer-drive method >>>>> was to save time. Is there more to 
>> it?>>>>>>>>>> --  Tom Fine>>>>>>>>>> ----- Original Message ----- 
>> From: "Jim Sam" >>>>> To: >>>>> Sent: Wednesday, January 20, 2010 
>> 12:45 PM>>>>> Subject: Re: [ARSCLIST] DAT ripping>>>>>>>>>>>>>>>> 
>> All,>>>>>>>>>>>> First, Dave, that information is very 
>> helpful.>>>>>>>>>>>> That said, I didn't ask because I'm worried 
>> about the theory. I >>>>>> was asking>>>>>> for a collaborator in 
>> testing.>>>>>>>>>>>> The theory's been discussed before on this list, 
>> and I'm aware >>>>>> that more>>>>>> than one person/organization has 
>> experimented with this to some >>>>>> success. It>>>>>> was also 
>> *briefly *discussed at last year's conference in DC. >>>>>> 
>> However,>>>>>> every time I've seen a discussion about the topic, it 
>> has never >>>>>> come along>>>>>> with what matters to me: testing to 
>> make sure what's coming off
>> >>>>>> the DDS>>>>>> drive is the same (or better) data than what 
>> would go
>> down the >>>>>> AES/EBU>>>>>> pipeline.>>>>>>>>>>>> I'm still 
>> extremely interested in this situation, and after >>>>>> having had 
>> to>>>>>> deal with other similar formats, I've got ideas for testing 
>> that >>>>>> I'd like to>>>>>> do. But I don't have a working DDS 
>> setup here. I could build my
>> >>>>>> own, which>>>>>> I might do, but that's a can of worms, and 
>> there's
>> other things >>>>>> to be gained>>>>>> by having a collaborator in 
>> these tests.>>>>>>>>>>>> Thanks,>>>>>> Jim>>>>>>>>>> Richard L. Hess 
>> email: [log in to unmask]>>>>> Aurora, Ontario, Canada (905) 713 
>> 6733 1-877-TAPE-FIX>>>>> Detailed contact information: >>>>> 
>> http://www.richardhess.com/tape/contact.htm>>>>> Quality tape 
>> transfers --  even from hard-to-play tapes.>>>>>>>>>>
>>
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