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Tom, 

We may have had safeties for the albums in question, but I'm not sure. The
ME did not request them. I believe he may have sourced the tracks digitally,
as we never heard back from him again. 

Oddly enough, I did that particular project in the same room your mother
worked in nightly on MLP, so I know there were no equipment issues
contributing to this problem.

Glad to know you were able to rescue the Copland 3rd. Eager to hear the results!

Jeff

 

On Wed, 8 Apr 2015 07:33:48 -0400, Tom Fine <[log in to unmask]> wrote:

>This dovetails with what I said on two fronts:
>
>1. you can't just assume that you can bake a tape many times and it will
playback just fine each
>time. That's not been my experience. No one has done quantitative research
into what happens to the
>tape surface or the order of the magnetic particles from baking. I assume
something goes on that
>adds "fuzz" and "dullness" to the sound, some physical process related to
baking and cooling and
>sticky-shed itself.
>
>2. tapes DO wear out from too many playbacks. I've had this happen with
different kinds of tapes in
>my personal collection. Cassettes eventually develop a loss of level and
dullness, and they don't
>track Dolby correctly, especially Dolby C. Reels get dulled down and peak
levels drop off somewhat.
>I assume that the oxide surface literally gets worn down each time it plays
and obviously some oxide
>is always coming off or we wouldn't need to clean heads and guides. I also
think there's low-level
>magnetism issues going on, not exactly sure where or how, but it's some
sort of slow low-level
>erasure mechanism.
>
>Jeff, what did the mastering engineer eventually do? Did you have safeties
in the vaults?
>
>In a modern context, copy tapes CAN be used to make great-sounding modern
reissues. Listen
>particularly to the Copland 3rd mono (Dorati/Minneapolis) in MLP Box 3.
That was a BADLY MADE dub,
>unusable until modern times. It was all that was in the vault. Aside from a
poor-sounding sonic
>spectrum as played with no expert mastering touch-up, it was full of wow
and flutter. We used
>Plangent Process to transfer and fix the time-domain problems. First of
all, the wow and flutter was
>fixed. Second, the smearing effects of the dub generation were eliminated,
so instruments were in a
>specific place and there was a surprising depth of field for a 1953 mono
recording. The
>sound-picture stabilized and the dynamics lit right up. With expert
mastering EQ nip and tuck by
>Andy Walter at Abbey Road, we got a really nice result. My point is, you
can use dub tapes and get
>good results, and sometimes it doesn't even take that much work. The caveat
is, you need to use
>modern methods and processes to get the good results.
>
>-- Tom Fine
>
>----- Original Message -----
>From: "Jeff Willens" <[log in to unmask]>
>To: <[log in to unmask]>
>Sent: Wednesday, April 08, 2015 1:06 AM
>Subject: Re: [ARSCLIST] More tales of woe from the tape vaults
>
>
>> Worn out tapes are absolutely in the vaults right now, and have been for
>> some time. I've come to find out (and perhaps others can correct me), that
>> there is a finite number of hours a polyester-backed tape may be baked
>> cumulatively before it stops working on the binder and/or it stops giving
>> the fidelity it used to offer.
>>
>> As for tapes in record company vaults, having worked at more than one major
>> label, I can say that you just don't know who's been on a tape before you
>> get hold of it. Some engineer may have tried to play a shedding Ampex 456
>> tape for a transfer without baking it, and lost a ton of oxide in the
>> process years before you. If so, there went your high end, and all your
detail.
>>
>> I had to do tape transfers of a very prominent 70s R&B band (who will remain
>> nameless) for an outside mastering engineer doing a CD compilation. They HAD
>> to be from the "original masters". All the masters were on Ampex 456 and 406
>> 1/4". All had been baked and used scores of times over the years. I checked
>> and baked the tapes for our usual amount of time, set up my machines, did
>> the azimuth, etc. All was set to go. I put up the tapes. And they sounded
>> like crap. Every last one of them. I double checked my entire set up. I
>> checked the tape path. I had other engineers checking everything. Nothing
>> made sense. All the tapes sounded like I was playing them from the outside
>> -- muffled, muddy, and smeared. Still, I transferred them flat and sent them
>> on.
>>
>> 2 days later, an extremely irate mastering engineer called me up and
>> demanded to know why I transferred the tapes inside out. When I explained
>> what happened, he couldn't believe the tapes could just "wear out" like
>> that. But that is what happened. They were utterly shot. No amount of
>> baking, EQ, azimuth tweaking, or sonic wizardry at the time was going to
>> bring these things back from the dead. The ME used other sources.
>>
>> So it's not necessarily "shelf life" that contributes to a reel of tape's
>> demise, but the use and handling it may get over the years that does the
>> ultimate damage. And that damage can be irreparable.
>>
>>
>>
>>
>>
>> On Tue, 7 Apr 2015 19:06:13 -0400, Robin Hendrickson
>> <[log in to unmask]> wrote:
>>
>>>I had a conversation once with someone who worked in the
>>>Capitol/EMI/Universal system, and this person told me that the "the
>>>old tapes are wearing out" and that all tape has a maximum shelf life
>>>of 30 – 40 years.
>>>
>>>That sounded like BS to me; I know there are older tapes out there
>>>that still work fine. (No guarantees, of course.)
>>>
>>>This Tom Petty story made me wonder whether there is some fallacious
>>>conventional wisdom out there that would lead one to rush to a verdict
>>>of "Yep, no way these old tapes are gonna work, we have to use
>>>something else."
>>>
>>>The mind reels. Excuse the pun, this is a serious matter indeed.
>>>
>>>Robin
>>>
>>>
>>>
>>>On Tue, Apr 7, 2015 at 5:26 PM, Richard L. Hess
>>><[log in to unmask]> wrote:
>>>> On 2015-04-07 3:18 PM, Eric Jacobs wrote:
>>>>>
>>>>> 2-inch tapes with sticky shed may not respond as well to baking as
>>>>> 1/4-inch.
>>>>>
>>>> That is true in the sense of in the same or similar time frame.
>>>>
>>>> I don't think there are precise formulae for predicting the time either to
>>>> achieve thermal equilibrium or to achieve moisture equilibrium in a tape
>>>> pack. Vos (1994) inspired me to develop a rule of thumb that moisture
>>>> equilibrium appears to take 1500 times as long as thermal equilibrium in a
>>>> one-inch tape, based on my extrapolations from his curves.
>>>>
>>>> We have long suspected that the width of the tape was a large modifier of
>>>> this ratio. I based my estaimate on Vos's graphs which seemed to indicate
>>>> that a 1-inch tape pack, might achieve thermal equilibrium might in 100-200
>>>> minutes while it might take 100-200 DAYS to achieve moisture equilibrium. I
>>>> felt that a factor of 1440 implied far too much precision in the
>>>> calculation, so I rounded it to 1500.
>>>>
>>>> Further pointing to this is what Stuart Rohre has reported on the Ampex
>>>> mailing list and elsewhere. He has been responsible for retrieving the most
>>>> information possible from some 1-inch instrumentation tapes which are
>>>> 15-inch diameter tape packs on glass precision Corning reels with no
>>>> windows. The windowless reels further slow moisture diffusion. He had
>>>> originally said they were baking for several days and could get through
>>>> about half the tape and then had to rebake, but they also had to run the
>>>> tape through their Bow tape cleaners. Partially at my suggestion and
>>>> partially on his own initiative, Stuart found that if he baked the
tapes for
>>>> 30 days, they would play through without the need for any tape cleaning or
>>>> re-baking and he was getting very clean signals off the tapes at that
point.
>>>>
>>>> So, are the two-inch tapes not responding to baking or simply in need of
>>>> more of it?
>>>>
>>>> One 7-inch reel of 1/4-inch tape that had been exposed to high humidity
>>>> cycles overnight had a very easy-to-remove mag coat when first inspected.
>>>> When it was stored in my air-conditioned home (minus the economizer cycle
>>>> bringing in Los Angele's famed "Marine Layer" of "night and morning low
>>>> clouds") for 3-4 months, the same test that initially showed mag coat
>>>> removal could not be duplicated and the tape binder seemed very secure at
>>>> that point.
>>>>
>>>> The "more baking" concept pertains to tapes like Ampex 456, 406, and 407 as
>>>> well as the instrumentation tapes made by Ampex at about the same time. It
>>>> may also apply to Scotch 226 and 227 and possibly Scotch 250. It probably
>>>> does not apply to Agfa tapes which have some of their own nastiness.
>>>>
>>>> This web page attempts to categorize tapes by degradation modality, and
>>>> degradation modalities are currently described more by what can ameliorate
>>>> their effect than by the actual chemical/mechanical failure modes. My
>>>> decade-long goal of a "pool-test kit" for tape degradation measurement is
>>>> farther in the distance than it was when I started the quest.
>>>>
>>>>
>>
http://richardhess.com/notes/formats/magnetic-media/magnetic-tapes/analog-audio/degrading-tapes/
>>>>
>>>>
>>>> Cheers,
>>>>
>>>> Richard
>>>> --
>>>> Richard L. Hess                   email: [log in to unmask]
>>>> Aurora, Ontario, Canada                             647 479 2800
>>>> http://www.richardhess.com/tape/contact.htm
>>>> Quality tape transfers -- even from hard-to-play tapes.