The original question was posted from someone in the US. So yes, all of
the (very interesting) answers were based on "US-centered" speeds.
Corey
Corey Bailey Audio Engineering
www.baileyzone.net
On 4/24/2017 3:42 PM, George Brock-Nannestad wrote:
> From: Patent Tactics, George Brock-Nannestad
>
>
>
> Hello,
>
> all very US-centered, isn't it? The 78.26 comes from a certain number of poles
> in a synchronous motor combined with simple ratios in the gearbox that changes
> the rpm from the motor to the target rpm for the turntable. But it is only this
> figure at 60 Hz mains frequency. If you had a slow-speed synchronous motor run
> off 60 Hz the closest to 78.00 is 78.26 rpm. If you use a stroboscope for 60 Hz
> under a 120 Hz light (goes for fluorescent or low-power incandescent lamps off
> the mains), you can only get a stationary ring at 78.26.
>
> In the not insignificant parts of the world where they use 50 Hz as the mains
> frequency, the corresponding figure would be 77.92 rpm. You need a different
> stroboscope for this and also the slow-speed synchronous motor would have a
> different number of poles. Aida Favia-Artsay knew, and her Caruso stroboscopes
> came in both varieties.
>
> The Victor Talking Machine Company is on record in the acoustic period as
> specifying 76 rpm for recording and 78 rpm for reproduction of the recording
> obtained. Some of their customers obviously did not have absolute pitch. In the
> acoustic period of the Gramophone Company, the speed was checked every morning
> by means of a piece of cigarette paper under the wax while cutting and counting
> the revolutions for a minute. They preferred 78 rpm!
>
> In the United Kingdom, the Old Philharmonic Pitch (which corresponded to an a4
> of 452 Hz (give or take a few) survived in the military bands until ca. 1926,
> when they also changed to the New Philharmonic Pitch at 439 Hz. If you hear
> Nellie Melba sing accompanied by the Band of the Coldstream Guards in 1905 with
> the key indicated, you can pitch it absolutely correctly when you play it: they
> used the Old Philharmonic Pitch. Columbia recorded a lot of military bands, and
> they abandoned the 80 rpm speed for 78 rpm at around the same time the bands
> changed tuning. The interesting thing is that the fraction 78/80 is very nearly
> the same as the fraction 439/452, in other words if you played a Columbia band
> record in 1932 you would not know whether it was an early recording slowed down
> to 78 or whether it was actually a new recording with the new pitch and the new
> speed. This is what I habitually in my workshops call "the dialectic triangle:
> speed, key, and standard pitch".
>
> I rarely comment these days, but this issue is very important.
>
> Best wishes,
>
>
> George
>
> ---------------------------------------------
>
>
>
>> 78.26 did not become a standard speed until electric motors were used in
>> cutter and playback turntables. In the acoustic era, 78 usually meant 78.00.
>> But, if you´re using a modern turntable like, say, a Technics SP-15, 78
>> actually is 78.26, and the percentage of change must be calculated from
>> that.
>>
>> Gary
>>
>> ____________________________
>>
>> Gary Galo
>> Audio Engineer Emeritus
>> The Crane School of Music
>> SUNY at Potsdam, NY 13676
>>
>> "Great art presupposes the alert mind of the educated listener."
>> Arnold Schoenberg
>>
>> "A true artist doesn't want to be admired, he wants to be believed."
>> Igor Markevitch
>>
>> From: DAVID BURNHAM [mailto:[log in to unmask]]
>> Sent: Monday, April 24, 2017 6:05 PM
>> To: Gary A. Galo
>> Subject: Re: [ARSCLIST] How many half-tones from 78 rpm to 80 rpm
>>
>> That's fine, but the standard speed for 78s IS 78.26; I don't know if 80RPM
>> records included a fraction. LPs, of course are always based on 33 1/3 RPM,
>> so there would be no reason to relate anything to 33.00 RPM. I'm sure the
>> original question was searching for a corrective adjustment to adapt from
>> standard 78 to Columbia's 80 RPM, but that's only a guess.
>>
>> db
>>
>>
>>
>> On Monday, April 24, 2017 5:56 PM, Gary A. Galo
>> <[log in to unmask]<mailto:[log in to unmask]>> wrote:
>>
>> I specifically said 78.00 in my reply. I assumed that if you meant 78.26, you
>> would have said so.
>>
>> Gary
>>
>>
>> -----Original Message-----
>> From: Association for Recorded Sound Discussion List
>> [mailto:[log in to unmask]<mailto:[log in to unmask]>] On Behalf
>> Of DAVID BURNHAM
>> Sent: Monday, April 24, 2017 4:44 PM
>> To: [log in to unmask]<mailto:[log in to unmask]>
>> Subject: Re: [ARSCLIST] How many half-tones from 78 rpm to 80 rpm
>>
>> Are you basing that on 78.00 RPM or 78.26 RPM?
>> Not challenging you just a question.
>> db
>>
>> On Monday, April 24, 2017 4:18 PM, Gary A. Galo
>> <[log in to unmask]<mailto:[log in to unmask]>> wrote:
>>
>>
>> A quarter tone is 3%, a half tone is 6%, and a whole tone is 12%. So, the
>> difference between 78.00 and 80 is just a hair under a quarter tone. A quarter
>> tone would be 80.34; a half tone is 82.68..
>>
>> Gary
>>
>> ____________________________
>>
>> Gary Galo
>> Audio Engineer Emeritus
>> The Crane School of Music
>> SUNY at Potsdam, NY 13676
>>
>> "Great art presupposes the alert mind of the educated listener."
>> Arnold Schoenberg
>>
>> "A true artist doesn't want to be admired, he wants to be believed."
>> Igor Markevitch
>>
>> -----Original Message-----
>> From: Association for Recorded Sound Discussion List
>> [mailto:[log in to unmask]<mailto:[log in to unmask]>] On Behalf
>> Of James Roth
>> Sent: Monday, April 24, 2017 3:31 PM
>> To: [log in to unmask]<mailto:[log in to unmask]>
>> Subject: [ARSCLIST] How many half-tones from 78 rpm to 80 rpm
>>
>> Hello everybody,
>>
>> Can anyone tell me how many half-tones up from 78 rpm to 80 rpm?
>>
>> Thanks.
>> Ben Roth
>>
>>
>>
>>
>
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