I think the first A301s were styled "Dolby S/N Stretcher", which I suppose 
is logical. Decca's tape box labels had a tick box for "stretched".



----- Original Message ----- 
From: "Tom Fine" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, February 09, 2016 11:49 AM
Subject: Re: [ARSCLIST] Playing reels backwards - separating myth from fact


> Copying Dolby tapes WITHOUT decoding them was definitely the conventional 
> wisdom in studios in the 70 and 80s, as I recall. I think it was Dolby's 
> recommended M.O.
>
> Question - where did the term "stretched" come from in relation to Dolby 
> encoding? What was being "stretched"? Certainly not the average level, 
> because Dolby calibration required closer attention to VU meters (and 
> keeping peaks out of the red zone), if you did it by the book. I always 
> likened that aspect of Dolby NR to typical UK and European disk-cutting, 
> in that a quieter background allowed for lower average levels. Of course 
> with pop/rock records from the early LP days to the mid-60's, there's the 
> issue that UK and European versions often featured longer sides so had to 
> be cut at a lower average level to fit all the real estate. Anyway, 
> though, "stretched"???
>
> -- Tom Fine
>
> ----- Original Message ----- 
> From: "Dave Burnham" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Tuesday, February 09, 2016 3:43 AM
> Subject: Re: [ARSCLIST] Playing reels backwards - separating myth from 
> fact
>
>
> Actually back in the Dolby A days I copied many encoded tapes without 
> decoding them. On decoding, the Dolby will address ALL of the hiss 
> regardless of how many generations there are. There will be losses such as 
> cumulative frequency response errors and compounded distortion but those 
> would happen anyway, even if you decoded and encoded for every dub. If you 
> don't decode/encode when you copy, you'll avoid all of the errors 
> introduced by the Dolbys themselves.
>
> db
>
> Sent from my iPhone
>
>> On Feb 9, 2016, at 1:09 AM, Corey Bailey <[log in to unmask]> wrote:
>>
>> I need to remind everyone that I never made a backwards copy of an 
>> encoded (stretched) tape, regardless of the noise reduction employed. I 
>> was there when the "to decode or not decode" controversy was at it's 
>> height. My position was (and still is) to decode the original and 
>> re-encode the copy. Reason: If you make a copy of an encoded tape without 
>> decoding it, the copy will have baked in tape hiss that will ultimately 
>> not be affected by the noise reduction when applied for final playback. 
>> Thus, the copy will be nosier than if you decoded and re-encoded the 
>> copy.
>>
>> Cheers!
>>
>> Corey
>> Corey Bailey Audio Engineering
>> www.baileyzone.net
>>
>>> On 2/8/2016 9:19 PM, Jeff Willens wrote:
>>> Actually, that was the one thing I always heard you could NEVER do with
>>> Dolby encoded tapes -- dub them without decoding them.
>>>
>>> I'm going back 15 years or so to remember this, but it is possible I did 
>>> not
>>> decode the Dolby on some of the analog copies I made, probably for test
>>> purposes. As I said, decoding backwards was not my preferred method, but 
>>> no
>>> one seemed bothered by my concerns. I did the dubs per the request of 
>>> the
>>> reissue producer. If there were residual decoding artifacts, I never 
>>> heard
>>> them or heard about them from the others involved.
>>>
>>> On Mon, 8 Feb 2016 21:23:34 -0000, Ted Kendall
>>> <[log in to unmask]>  wrote:
>>>
>>>
>>>> This runs counter to my own experience. Firstly, one great benefit of 
>>>> Dolby
>>>> A was that straight copies of encoded tapes could be made without 
>>>> decoding,
>>>> provided that the reference tones were retained on the copy, so there 
>>>> was no
>>>> need to decode as part of the dubbing process. Secondly, to decode a 
>>>> Dolby A
>>>> tape on reverse play is just plain wrong - the attack and decay
>>>> chracteristics of the system are asymmetrical, so the decoding will be
>>>> wrong, no matter how much you have finessed the other parameters.
>>>>
>>>>
>>>>
>>>>
>>>> ----- Original Message -----
>>>> From: "Jeff Willens"<[log in to unmask]>
>>>> To:<[log in to unmask]>
>>>> Sent: Monday, February 08, 2016 1:22 PM
>>>> Subject: Re: [ARSCLIST] Playing reels backwards - separating myth from 
>>>> fact
>>>>
>>>>
>>>> I should think the net gain depends on the type of music involved. Back 
>>>> at
>>>> Universal, I was asked by a producer to make 1:1 analog copies of album
>>>> masters played in reverse to be sent out for mastering. The thinking 
>>>> was
>>>> exactly as you describe: sharper transients, better bass response and
>>>> definition,etc. Since these were all reggae albums from the 70s and 
>>>> 80s,
>>>> they felt it was worth the effort.
>>>>
>>>> In my own crude testing, I found that, aside from making sure the 
>>>> channels
>>>> were consistent (something one can easily overlook), I also found 
>>>> azimuh to
>>>> be the crucial factor in achieving any success, Many masters were Dolby
>>>> encoded, which gave me much pause, but no one else was concerned about 
>>>> it (I
>>>> figured decoding between the two tape machines was the least of all 
>>>> evils).
>>>>
>>>> Was there a difference? Hard to say. I believe there was a slightly 
>>>> better
>>>> result from  reverse transfer, but nothing drastic. And definitely 
>>>> nothing
>>>> that couldn't be got with skillful use of modern compression and EQ.
>>>> =========================================================================
>>>