From: Patent Tactics, George Brock-Nannestad
Don Andes took the challenge, and Mike Richter, David Lennick, and Steven
> As some of you may have already guessed, I'm open to crazy ideas, so I'll
> pursue the logic of creating 78's as an archival medium, since they have
> been hanging around in vaults for a good long time.
> But I have the following questions in regards to 78's:
> What is the maximum uninterrupted record time?
> What is the maximum fidelity expectation?
> Could the format possibly handle multi-channel recordings?
> If there any way to embed a video track (if you will) to address audio that
> is required to sync with a video source?
> Could you possible embed a data track to handle metadata since Physical
> labels have limited space, can fall off, or become obscured?
> In today's world of chemical regulations, is it still legal to make a 78
> record, or does include some gaseous by-product, or radioactive waste?
> Without viable real world answers to ALL the questions above, I believe I
> for one would take the idea of using 78's as non-viable.
> Any takers?
----- I am a taker:
A direct answer to your questions does not provide suitable information for a
decision maker, because they would address limitations that must be
considered artificial today.
First of all I would think that the expression "78" is just a symbolic
expression for "mechanical modulation". The fixed rpm value 78 merely
established itself as a relevant value in the period ca. 1894-1962 (in the
Western world). This was in the period in which the material contained 80%
slate dust, held together with a suitable binder; from a manufacturing point
of view it was shellac for a very long time.
Joseph Maxfield established the relationship between uninterrupted record
time, maximum amplitude and rpm in 1925, but that was when only a fixed
groove pitch was available. With variable pitch (that was commercialized in
the 1950s), you could get e.g. 15' on a 78 rpm side, dependent on recording
The larger the volume taken up by modulation is, the safer the signal. 78s
have coarse grooves, i.e. a large volume, and two huge flanks, each 100
microns (4 thous) in "height". This was required when the tracing stylus was
a steel needle. Once the microgroove came along ca. 1950 (known as 33 and 45
respectively), all development of coarse groove pickups stopped, and the
efforts were thrown at the new format. Many modern pickups are quite able to
cope with the required recorded velocities for 33 and 45, but they are no
longer able to provide a linear velocity signal when the recorded amplitudes
approach those of coarse groove records. As an aside, this is one of the
reasons why some click and crackle removers have problems: when the noise
impulses are traced near the max excursion, the recorded velocity (that is
the signal we want) is very low, almost zero, but the representation of the
noise waveform has suffered distortion and is more difficult to handle. A
disco pickup is much more capable, as it has to deal with a 45 rpm disco
single - which has coarse grooves in stereo!
So, if we now move from the high and safe rpm 78 and to the standards between
ca. 1950 and - today, i.e. 33 1/3 rpm and 45 rpm, there are many things that
can be done. If we accept sophisticated data and signal processing when we
transfer to digital, why should we not also accept this for mechanical analog
recording? If we open that field, we can obtain all kinds of multichannel and
synchronization, some of it using proven recording technology (SQ and other
four-channel recording systems did work, but the mechanical reproduction was
difficult), and using state-of-the art (vintage 1987) optical replay (such as
the ELP Laser Turntable). Variable speed to provide linear surface speed
under the writing and later the reading head could be synchronized by a
wobble-like signal (like in the pre-groove of a CD-R).
AS you will note, the field is rich for standardization; on the other hand,
if this is professional only, why bother. The digital solutions made
available today are definitely not adhering to international standards;
something that will be sorely felt if re-formatting (migration) has been
pushed too late for the endlessly-happening overlap window.
The record material is one interesting area. The idea of using slate dust (as
the "loading") with shellac binder (and some lubricants and the inevitable
carbon black) was to make an aggregate that worked in principle like
concrete, only on a smaller scale. Good aggregate requires both large
particles and smaller and very fine particles, in order that it can pack and
carry a load. For steel needles providing a side pressure in the groove this
was an exellent idea. When all modulating forces were vertical, as in the
Edison Diamond Discs, it was possible to use not only very fine grooves in an
unloaded phenolic material but also huge pressures requiring a polished
diamond - but the wear was still tolerable. I feel very confident that we can
find an environmentally acceptable material as a binder and obtain a fine
surface that will not be worn, because of optical replay. So, our only worry
will be the environmental maintenance of the surface. Still, if we are only
considering a professional format, what is the matter with storing nickel
mothers? A negative is much too sensitive, because the information is lifted
above the plane, but in a positive all the information is below the surface
called the land. Copper mothers have also been demonstrated to have a very,
very long life, provided they are given a suitable coat that may be removed
by steam or the similar. This was done in matrix stores in India in the
1910s, to protect the investment from corrosion.
The metadata is another area: a data track is only relevant if we are now
discussing digital signals stored without need for migration because it is on
a very durable carrier. In a pressing of an analog recording an embossed
label would be quite sufficient, based on engraving the original metalwork.
It will not fall off. On a nickel mother, there could be direct engraving or
laser ablation in the central surface of the record that is not used for
All the above addresses the question of creating an analog system for long
term preservation and retrieval. Those recordings that are already in the
suggested format (nickel mothers, protected copper, shellac/slate dust)
"only" need a reasonable environment for their survival.
I feel that it has not been in the manufacturing (including the record
industry) industry's interest to provide backwards compatibility when they
are creating systems to enhance the value to customers (and themselves). We
have been dependent on the manufacturing industry for low-cost solutions, the
larger the scale of manufacturing the lower the cost. This development now
comes back to bite the record industry, and we cannot even say "serves them
right", because they are the holders of a large part of the commercial
recorded history. And if they give up it may be lost. Preventing others from
giving access by means of draconic copyright measures adds to the insult.
If you have read this far, you may still dismiss my technical arguments as
"speculative". Let me say that I have cut, and still do, lacquers, waxes,
Direct Metal Masters, and cylinders, both by the electrical method and
acoustically, using recording horns and soundboxes from the period in
question. I have etched grooves, Berliner style (using copper and not zinc,
because of crystal boundaries). I have full control over the parameters,
which is more than can be said for recording a CD-R. And I should mention
that Cornell University in their wild-life sound work regarded wax mastering
as much better than lacquer as late as 1960 (personal information from Dave
Wickstrom). The frequency range requirement for bird song is high. The only
reason that mechanical recording went out of fashion is that the novelty had
worn off after 90 years.
I hope that there will somewhere be a forum where realistic approaches to
analog long-term storage without the need for migration may be discussed.
Cost calculations are possible on every level, so we can effectively move
away from daydreams. The amount that may need storage is daunting but that is
no different from all other long-term documentation of human endeavours.