Yes and, although off topic:
When the transition form 50Hz to 60Hz, was undertaken, the Los Angeles
Department of Water and Power (known locally as DWP) set up a program
whereby the local citizens could have their electric clocks converted
for free.
Regards,
Corey Bailey
On 11/27/2015 12:30 PM, Eric Jacobs wrote:
> I was surprised to learn that 50Hz was common in Southern California.
> Southern California Edison used 50Hz until 1948 - and I have evidence
> that the transition to 60Hz was not complete until late 1949 (at least
> in the area that served Beverly Hills and some of the film studios).
>
> ~ Eric Jacobs
>
>
> On 11/27/15, 10:05 AM, "Association for Recorded Sound Discussion List on
> behalf of John Haley"<[log in to unmask] on behalf of
> [log in to unmask]> wrote:
>
>
>> The fundamental of the hum, at either 60 cycles or 50 cycles, is still one
>> of the most reliable "clues" to getting the pitch "right." All of the
>> issues discussed mean that this issue will always be something of a
>> struggle, and certainty is not always guaranteed.
>>
>> Pitch has been standardized, tho not always reliably, at A = 440, since
>> the
>> 1920's, but of course there are exceptions. Several major orchestras
>> (Boston and Minneapolis, for example), deliberately tuned sharp in the
>> 1940's to get a more brilliant sound. But unless a reason for an
>> exception
>> is known, A=440 is still the best choice in many instances. For example,
>> studio-made pop records that include studio musicians, made during the
>> 1950's will not likely be tuned oddly. But "in the field" folk recordings
>> or gospel recordings could be anything (unless there is an electronic
>> organ
>> being used, which might be reliable). Church pianos are notoriously not
>> tuned for years, and over time a piano will often sink in pitch, so if the
>> piano is out of tune generally, look out. But it is always good to check
>> the hum. It really should not vary much from 50 or 60.
>>
>> On vocal recordings, listen a lot to the accompaniment!
>>
>> Despite all these problems, getting the pitch "right" is one of the most
>> critical things an audio restorer has to address. Changes of even a
>> fraction of a half step can make quite a difference, particularly for
>> human
>> voices. In today's world, it is a real sin not to at least try to get the
>> pitch right, and I mean really right, not within a "range" of right.
>>
>> I am restoring a mono RCA LP right now from the early 1950's, a
>> compilation
>> of the same artists, obviously recorded at different times and places as
>> the tracks do not share the same "sound" for the space they were recorded
>> in. The first two tracks on Side 1 required a drop of 4%--they were
>> playing way sharp, even tho I dubbed the record at 33.33 RPM. I thought,
>> OK,since the first two match, the rest should be the same. Nope. The
>> next
>> track required a correction of -1% to be dead on pitch, etc.
>>
>> Best,
>> John Haley
>>
>>
>>
>>
>>
>>
>> On Fri, Nov 27, 2015 at 12:42 PM, Jolyon S Hudson<[log in to unmask]>
>> wrote:
>>
>>
>>> Dear Andrew
>>>
>>> Sorry for going off at a tangent, easy done!
>>>
>>> It is possible that the power supply was not all that it could be. It
>>> may
>>> have
>>> been expedient to either drop the frequency or, more probable, the draw
>>> on
>>> the
>>> power stations was such that the generators lost momentum at certain
>>> times
>>> in the day.
>>>
>>> This is what happens even today when a blackout is tripped - too much
>>> energy
>>> being pulled from the grid and the network collapses as generators can't
>>> keep
>>> up with the demand. To alleviate this you can drop the frequency.
>>>
>>> I don't know enough about the power supply in Argentina I'm afraid but
>>> knowing that between the early 1930s and 1990s the Argentine economy
>>> progressively deteriorated I don't doubt that the power supply was not
>>> all
>>> that it
>>> should be.
>>>
>>> The power supply in the US and most other counties would be fine most of
>>> the
>>> time. However during wars, economic problems, lunch time and dinner time
>>> (nice combination of events) things can droop a bit.
>>>
>>> I don't think that the frequency of hum is a sure way of getting the
>>> pitch
>>> right in
>>> recordings but it is fairly accurate most of the time but not a silver
>>> bullet.
>>>
>>> This or a combination with other factors could be part of the answer.
>>> This
>>> is
>>> why a number of recording companies kept to weight driven recording
>>> equipment as it theoretically guaranteed a constant speed.
>>>
>>> Jols
>>>
>>>
>>
>
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