I forgot to mention one other element of this -- bias recovery. Theoretically, a superior magnetic
head and high enough resolution digital transfer should recover bias frequency on the tape. In fact,
perhaps a second head optimized for bias frequencies and staggered a standard distance from the
audio head could be used, and bias assigned to a separate digital file with offset information
provided in the metadata. This can then be used with Plangent or other process to correct any
wow/flutter or speed variations in the original master recorder. This also fits in with the concept
that what is being made in the A>>D transfer is essentially a direct copy of the magnetic media
instead of a playback of the recorded signal.
-- Tom Fine
----- Original Message -----
From: "Tom Fine" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, July 28, 2008 7:40 AM
Subject: Re: [ARSCLIST] Playback on contemporary machines (was Send me a kiss by wire, baby my
heart's on fire!
>I was thinking further about this. There's a big money opportunity in here, if someone runs with
>this and finds it, buy me a steak dinner sometime ;)!
>
> For the commercial copyright owners, it seems to me that this concept may offer an excellent and
> highly-accurate way to once and for all migrate their tape libraries off of the deteriorating
> original media. Even under archival storage, many tapes are nearing the end of their functional
> lives, and some masters have been played enough times as to be badly deteriorated already.
>
> Here would be one system I could see as being viable and very sensible for a large music company:
>
> 1. a super-precise tape transport with excellent-quality magnetic heads is used to transfer the
> raw signal off the tape. The transfer should probably be to both DSD (read on, there's sense to
> this) and high-resolution PCM. Much testing should be done to make sure that the digital system is
> as precise and accurate as is possible for the formats (which, if the resolution is high enough,
> should theoretically mean that just about every bit of meaningful information should be
> transferred from the magnetic tape).
>
> 2. the standard operating MO from here would be to have these digital files live in a very robust
> archive with as fail-safe as possible replication, migration and backup. This is more in the realm
> of an IT expert than a music company and I would suggest there is an outsourcing model that makes
> some sense here.
>
> 3. for run-of-the-mill reissues (ie stuff with budget and time constraints), the remastering could
> be done all DSP, probably all or mostly automated. I would expect a middling but not terrible net
> quality level here, and over-aggressive use of DSP extras like dynamics control and hiss-reduction
> would probably degrade the net result, but tasteful application of the usual mastering tools
> (which would run up the budget since human hands and skills would be required) could improve the
> average quality substantially.
>
> 4. here's where the DSD transfer could come in. Perhaps the record company itself, or a specialty
> mastering house, would rig up an interface between a DSD stream and a rack of different tape
> electronics (it's a simple level and impedence matching thing -- and the intial input stage can be
> bypassed on some tape electronics with 10 minutes of solder time). These "deluxe" remasters would
> be "played back" to gain the desired euphonic results. Meanwhile, the tapes would not have to be
> played again and the "warm analogue sound" from the tape electronics could be gained in any
> combination or tweak desired. The further benefit is no need to maintain a precise mechanical
> transport, just more-simple electronics maintenance. But the big win here is, the master tapes
> don't get played and transported in their fragile condition. Assuming the transfer at the source
> was done properly (ie azimuth was correct and the A>>D chain was superb), this would be audibly
> identical to playing back the actual tape using the heads used at the source.
>
> 5. indeed, there may be an audiophile market in selling the raw digital transfer and letting the
> audiophile play it back thru the tape electronics of his choice. Never before could a listener be
> so close to the actual master tape. Again, the weak link here is that the source transfer needs to
> be azimuth-perfect and the A>>D chain needs to be superb.
>
> 6. a final benefit to the copyright owner is, he now has in his archive an unprocessed, uncolored
> and un-EQ'd version of the source, a digital "clone" of what is falling apart on the reel in the
> box. As technology, especially DSP, improves, he can hope to achieve better and better results
> even with the run-of-the-mill releases and can get out of the expensive business of analog
> expertise as the tapes crumble to dust.
>
> More morning musings. I have no idea how much of this is already being done and what is totally
> impractical about what I'm suggesting. And, as I said before, I have no dog in the fight -- except
> as a collector and fan desiring better reissues than are the norm.
>
> -- Tom Fine
>
> ----- Original Message -----
> From: "Tom Fine" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Sunday, July 27, 2008 1:37 PM
> Subject: Re: [ARSCLIST] Playback on contemporary machines (was Send me a kiss by wire, baby my
> heart's on fire!
>
>
>> Along these lines ...
>>
>> As DSP improves and higher-resolution and even DSD transfers become the norm, I'm wondering if
>> it's time to start thinking about eliminating the analog electronics altogether for non-NR tapes.
>> To wit -- a tape head connected directly, with proper impedence-matching, to a high-resolution
>> A-D converter, perhaps with one stage of gain between the head and the converter. The EQ curve
>> and level-normalling is then performed in the digital realm via DSP. The main advantages I could
>> see to this would be: 1) perhaps more accurate EQ curve than can be achieved with analog
>> components, but this may or may not be the case at the present state of the arts. 2) elimination
>> of all noises and distortions from analog components -- now it's a whole can o' worms whether the
>> DSP would just add less-euphonic distortions of its own. 3) perhaps less cost due to no need to
>> maintain and/or repair old analog electronics (even the solid-state stuff will wear out
>> eventually). 4) the creation of a market for digital-realm expertise in analog issues like EQ
>> curves and magnetic head interfaces, thus leading perhaps to some new and innovative
>> audio-cleanup/restoration tools and better analog-to-digital interfaces.
>>
>> I have no dog in this fight, just doing some Sunday musings on an interesting topic.
>>
>> One other point. As the world's fleet of tape machines get older, I think more and more are
>> falling permanently out of spec. I think it's a great stretch to expect a 50-year-old Ampex 350
>> to sound anything close to original unless you are a restoration expert and have done an expert
>> restoration on the machine or have paid plenty of $$$ to have it done by someone else. The same
>> can be said of just about any machine ever made that has more than a few hundred hours on it
>> and/or has not been stored in an ideal environment its whole life. And some machines have
>> built-in manufacturing or design weaknesses that cripple them over time no matter what. Belts
>> stretch and fall apart, for instance, even if the machine isn't used. Some of the connectors
>> used on MCI machines corrode, no matter what. Etc. etc.
>>
>> -- Tom Fine
>>
>> ----- Original Message -----
>> From: "Richard L. Hess" <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Sunday, July 27, 2008 1:06 PM
>> Subject: Re: [ARSCLIST] Playback on contemporary machines (was Send me a kiss by wire, baby my
>> heart's on fire!
>>
>>
>>> Hello, Mark and Jim and Shiffy,
>>>
>>> I think it's important that we reinforce the lesson of playing magnetic media on the best
>>> available equipment. While there are times when playing a tape on the machine that recorded it
>>> will provide the sound that the producer originally heard and intended, in most instances,
>>> playing a magnetic recording on a high-end, late-model (but not necessarily last-model) machine
>>> will provide superior results. This means that Shiffy's one-off device is probably the best
>>> device to reproduce a wire, and it means a small handful of the best tape machine models should
>>> be chosen and preserved for playing tapes. I won't bother enumerating those models here, as I
>>> think that list is well-known.
>>>
>>> The philosophical approach that works for me, and I suggest that everyone consider, is that
>>> machine perturbations are additive. Play deficiencies/perturbations rarely if ever "cancel out"
>>> record deficiencies/perturbations that are already recorded on the magnetic record. Therefore,
>>> the machine that adds the fewest deficiencies/perturbations that is compatible with the speed
>>> and track format (or can be made compatible) is generally the one to choose.
>>>
>>> There are usually other competing factors driving the selection of the reproducer, but having a
>>> machine to play the magnetic records with performance better than the record machine is
>>> generally the best way in my opinion/experience.
>>>
>>> Cheers,
>>>
>>> Richard
>>>
>>>
>>> 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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