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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" 
> <[log in to unmask]>
> To: <[log in to unmask]>
> 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" <[log in to unmask]>
>>> To: <[log in to unmask]>
>>> 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.
>>
>