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:>>>> 
> >>>>>>>>>>>> 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: >>>>> 
>>>>>> Quality tape transfers --  even from hard-to-play 
> tapes.>>>>>>>>>>