Wednesday, October 13, 2010

Scully Lathe

Just file this under irrational techno lust. The skully lathes are so cool.

The above may actually be a Neumann lather.







Thanks for the comment wbhist.

The Scullys of the 1950's and '60's (as on the 4th and 5th pictures shown) are my preferred variant. Lead-in grooves had spacing dimensions of 32.3125 and 7.625 lpi, with some having a "medium" spacing of 15.583333... lpi and most others' "medium" spacing being 14.7291667... lpi. Such lpi dimensions also applied to "spread" grooves that transported between one "band" and another on an LP record; and the 32.3125 and 15.583333... (or 14.7291667...) were used for "catch" grooves that came after the lead-out but preceded entry into the locked groove (this, I'm told, for the activation of automatic record changers). As for lead-outs, depending on what lathe was used by which studio, there were "slow" and "fast" moving turns, grouped as follows: 4.62 and 2.3 lpi; 4.17 and 2.14 lpi; 3.92 and 2.04 lpi; 3.83 and 1.98 lpi; 3.69 and 1.92 lpi; and 3.48 and 1.83 lpi. Those are the lathes with the knobs that turned anywhere from 70-400 lpi, or 105-600 lpi, or 140-800 lpi. Lathes as so constituted appear to have been manufactured as early as 1950, so I'm told.

The earlier lathe with a gear box as at photo bottom, its design dated back to c.1938. The lpi dimensions as shown were 88, 96, 104, 112, 120, 128 and 136 lpi. In this configuration, there were other sub-classifications. Columbia in New York had a lathe (in use from c.1939 up to August 1966) that had groupings of 150.1875, 163.6875, 177.1875, 190.6875, 204.1875, 217.6875 and 231.1875 lpi; while Aardvark Mastering's ancient Scully's finer grooves are 178, 194, 210, 226, 242, 258 and 274 lpi. Then there are even finer groups, with the "coarse" being 132, 144, 156, 168, 180, 192 and 204 lpi (plus, on Columbia's aforementioned cutter, 225.28125, 245.53125, 265.78125, 286.03125, 306.28125, 326.53125 and 346.78125 lpi).

As to the lathe on the top photo as originally on the cover of that Electronics World magazine: Looks suspiciously like a Neumann AM-32 to me.

6 comments:

  1. The Scullys of the 1950's and '60's (as on the 4th and 5th pictures shown) are my preferred variant. Lead-in grooves had spacing dimensions of 32.3125 and 7.625 lpi, with some having a "medium" spacing of 15.583333... lpi and most others' "medium" spacing being 14.7291667... lpi. Such lpi dimensions also applied to "spread" grooves that transported between one "band" and another on an LP record; and the 32.3125 and 15.583333... (or 14.7291667...) were used for "catch" grooves that came after the lead-out but preceded entry into the locked groove (this, I'm told, for the activation of automatic record changers). As for lead-outs, depending on what lathe was used by which studio, there were "slow" and "fast" moving turns, grouped as follows: 4.62 and 2.3 lpi; 4.17 and 2.14 lpi; 3.92 and 2.04 lpi; 3.83 and 1.98 lpi; 3.69 and 1.92 lpi; and 3.48 and 1.83 lpi. Those are the lathes with the knobs that turned anywhere from 70-400 lpi, or 105-600 lpi, or 140-800 lpi. Lathes as so constituted appear to have been manufactured as early as 1950, so I'm told.

    The earlier lathe with a gear box as at photo bottom, its design dated back to c.1938. The lpi dimensions as shown were 88, 96, 104, 112, 120, 128 and 136 lpi. In this configuration, there were other sub-classifications. Columbia in New York had a lathe (in use from c.1939 up to August 1966) that had groupings of 150.1875, 163.6875, 177.1875, 190.6875, 204.1875, 217.6875 and 231.1875 lpi; while Aardvark Mastering's ancient Scully's finer grooves are 178, 194, 210, 226, 242, 258 and 274 lpi. Then there are even finer groups, with the "coarse" being 132, 144, 156, 168, 180, 192 and 204 lpi (plus, on Columbia's aforementioned cutter, 225.28125, 245.53125, 265.78125, 286.03125, 306.28125, 326.53125 and 346.78125 lpi).

    As to the lathe on the top photo as originally on the cover of that Electronics World magazine: Looks suspiciously like a Neumann AM-32 to me.

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  2. Thank you for the comment. I have added this information to the poast.

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  3. Yes, the lathe in the top photo is a Neumann. From the photo it is hard to tell which model as they all used the same turntable up to the VMS70. The VMS80 did not have strobe markings as earlier machines did. The use of a Westrex head on a Neumann lathe was not too common. Crest Records in Long Island had a Neumann/Westrex configuration. Perhaps this is where the photo was taken.
    The third photo shows the last of the Scully Lathes, this was titled "The Lathe" when Scully introduced it. This new machine relied on a more complex variable pitch and depth system. Earlier machines used mechanical system (very clever, but not too accurate) to achieve groove spacing where the new machine utilized a computer to space and deepen grooves.
    The fifth photo shows the Scully lathe with the mechanical variable pitch system. The large pointer at the right side of the machine (on the table top) would read the lines per inch. This pointer in operation would physically move from course to fine pitch depending on program material. The base pitch (lines per inch the machine would cut with no modulation was set by turning the black control just to the right of the feed pointer. Turning this black control would cause the feed pointer to move to either a finer or courser pitch. Once set, the automatic variable pitch control would continuously adjust the pitch as the master tape was played.
    The sixth photo shows a fixed pitch machine. When I say fixed pitch, once the lines per inch were set, that was it for the entire side of the record with the exception of run in, run out and spiral. My first Scully lathe (built in 1939) was configured like this, but it had both a gear box as well as a belt change to allow pitch selection (from memory, I sold that machine many years ago) from 88 to about 340 lpi. This machine was later fitted with a Capps Computer (pitch and depth).

    By the way, I'm Carl Rowatti of Trutone Mastering Labs. www.trutonemastering.com

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  4. WoW

    Carl your studio is amazing.

    Thanks for all the information.

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  5. "The Lathe" which was the third picture was designated Model LS-76. As to the other vintage Scullys: the fourth and fifth pictures (with the pitch knob) would have been the Model 601 class, whilst the sixth picture (with the gear box) was a Model 501.

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  6. grizzly g0602 This is handy for pieced you are holding from just one end, such as a wood bowl. Your particular needs will dictate which of these features are most important for you.

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