Revolutions Per Minute

    Around the World in 80 Lathes, Part Three

    Issue 153

    In previous installments (Issue 151 and Issue 152), J.I. Agnew presented a historical overview of record-cutting lathes, and looked at some models from Neumann.)

    The suspension unit of the Neumann VMS-80 record-cutting lathe was similar (but not identical) to the one used on the previous VMS-70. Both had electronic groove depth control, electronic cutter head drop and lift, and an oil dashpot to provide damping. The pitch control computer used on the VMS-80 and VMS-82 was another milestone for Neumann, leaving behind their earlier systems.

    Technical details of the inner workings aside, the most notable change was a departure from the 0.6-revolution delay system used by Neumann in all their pitch automation systems since the 1930s, and the introduction of a new standard: The 0.5 revolution delay.

    In English, this refers to the delay required between the program signal and the preview signal. The preview signal is an additional signal, arriving in advance of the program signal, but fed to the lathe’s control electronics to enable the pitch and depth control automation systems to operate. Both the program and preview signals are the same audio signal, but with a time delay for the program signal, to allow time for the mechanical moving parts of the lathe to speed up or slow down as required.

     

    A Studer preview head tape machine, used at Salt Mastering, Brooklyn, NY. Courtesy of Paul Gold.

    A Studer preview head tape machine, used at Salt Mastering, Brooklyn, NY. Courtesy of Paul Gold.

     

    In the analog days, this was accomplished by means of a preview-head tape machine, of which very few were ever made, (see Issue 143 and Issue 135 for some examples). In the brave new world of the 1980s, many facilities had moved on to the use of digital delay lines (DDL) to delay the program signal, which was the beginning of the end of all-analog signal paths for cutting master disks for vinyl record manufacturing, even when the source was an all-analog recording on tape.

    With the move to a 0.5-revolution (platter revolution) delay, Neumann effectively rendered the VMS-80 and VMS-82 incompatible with all existing preview head tape machines (although Studer and Telefunken offered conversion kits, allowing the continued use of their existing products with the new Neumann lathe, and the final MCI preview head tape machine to be developed took this into account from the onset), even when these were used with earlier Neumann lathes, which made the use of DDL systems much more economically appealing, accelerating the death of 100-percent analog sound.

    The pitch control system was what we call “land-based,” and calculated the land between the grooves as a function of groove depth, diameter, the dynamics of the music, and a user setting for minimum land to be maintained. The minimum land could be set to zero, allowing the adjacent grooves to actually touch each other. The pitch computer calculated the angular position of the platter and adjusted pitch and depth so that the grooves could be nested together most efficiently. This system made it easy to cut much longer sides at much higher levels, even for a relatively inexperienced operator. This feature alone turned the VMS-80 into a real asset, as it made it possible to just purchase your competitive advantage, instead of having to painstakingly develop it over many years of excessive perspiration, hunched over a manually-controlled lathe in a hot cutting room, ruining lacquer disks faster than you could buy them, and trying to fit all the music into a disk with no mishaps.

    An average operator of a VMS-80 could cut records that were as loud or even louder, and with longer side duration, than what a very experienced mastering engineer could achieve using a much less technologically sophisticated machine. Unfortunately, this did not necessarily mean that these records would sound better, in audiophile terms. Just louder and longer, which was apparently enough to make the average consumer feel that they were getting more music for their dollar. For the businesses using the VMS-80, it greatly reduced the rejection ratio for lacquers. No matter who was cutting, it would somehow work.

     

    The vacuum platter on a VMS-82 DMM lathe, but connected to cut lacquer using a lacquer suspension box and a Neumann SX-74 cutter head. Courtesy of Scott Hull, owner/chief engineer, Masterdisk, Peekskill, NY.

    The vacuum platter on a VMS-82 DMM lathe, but connected to cut lacquer using a lacquer suspension box and a Neumann SX-74 cutter head. Courtesy of Scott Hull, owner/chief engineer, Masterdisk, Peekskill, NY.

     

    The vacuum platter on the VMS-80 and VMS-82 was also a new design, smaller and with a hidden, permanently attached vacuum fitting underneath the platter, instead of the traditional approach of a tube needing to be connected by the operator to the center spindle from above. The less an operator needed to do, the better for their ’80s hairdo.

    The platter was adjustable in a very similar manner to the earlier models, to eliminate any platter run-out (in mechanical terms). As the Neumann platters were quite well made, the top surface was already significantly flatter than any other machine made by their competitors, and the adjustment resulted in a very accurate rotating system. The platter bearings were hydrodynamic, running in oil and designed to prevent metal-to-metal contact. The shaft would run on an oil film.

    The speed regulation of the turntable motor was accomplished by means of an optical tachometer, which generated electrical pulses corresponding to the reflected light off of the teeth of a stroboscopic disk, sensed by a light-dependent sensor. The frequency of the generated pulses depended on the platter speed, and the servo control system would constantly adjust the drive to the DC motor to maintain a stable speed.

    Next to the platter bearing, there was a dovetail slide with a leadscrew, which advanced the cutter head across the disk. The dovetail slide ways were located below the platter and an L-shaped carriage arm would hold the suspension unit (containing the electronic depth control system, the head lift/drop system and the oil dashpot) and cutter head above the platter.

    The control panel of the lathe even had a stylus hours counter, so the operator could keep track of how long the cutting stylus had been in use.

    Gone were the days of using your ears to determine this based on sound quality. The modern, fast-paced world of the 1980s demanded that no time was wasted on meaningless exercises. The facility would determine how many hours the stylus needed to be used to maximize profit, the management would give the operators a number, and everyone could then happily go about their business while still having enough time to maintain that mullet hairdo, essential for maximum coolness points at the weekend synth-pop party which you would attend to lure in more customers who wouldn’t care much if the stylus was only replaced at set hour intervals.

    Admittedly, it was a useful feature, as one could also choose to use it simply to keep track of how long the styli were lasting, when comparing the products of different manufacturers, and still use their ears to determine when it needed to be thrown out. The VMS-80 and VMS-82 were the only disk mastering lathes that came with a built-in stylus hours meter from the factory.

    Another innovation was the updated illumination system on the Leitz groove inspection microscope, which was mounted on its own slide tube, above the platter. Unlike previous microscope installations, this one had remote illumination, transmitted through optical fibers to the bottom of the objective lens. Two optical fibers were arranged in a 45/45 configuration to illuminate each groove wall directly, eliminating shadows and improving visibility. The microscope assembly also had the option of mounting a Newicon camera picture tube, which could be used to display the groove image on a TV monitor, to entertain the (mullet-bearing) studio guests.

    The 1980s was the decade of glitter, strange haircuts, and especially in Germany, strange music (ever heard of Einstürzende Neubauten?), so Neumann engineers did the geeky equivalent: magnified Groove images displayed in real time, in color, on a TV monitor.

    So, what do you think happens when product support is suddenly withdrawn from a highly proprietary and regulated system such as DMM?

    No more blank disks, no more styli, no more fun!

    By the 1990s, flannel shirts and long hair had replaced glitter and mullets, and Nirvana has become more popular than Einstürzende Neubauten, so Teldec and Neumann decided to finally leave the disk mastering market altogether. For a very long time, nobody even attempted to take their place.

    As lacquer blanks were a much older technology that was not regulated by patents, there were a couple of manufacturers still left operating (well, until one bought out the other to shut them down and eliminate competition), as well as a couple of cutting styli manufacturers (up until there was only one left, who was owned by one of the lacquer manufacturers, who refused to sell styli unless you were also purchasing a certain amount of their lacquers each month, trying to drive the competing lacquer manufacturer out of business).

    As the mechanical system of the VMS-82 DMM lathe was almost identical to the VMS-80 lacquer lathe, and the latter was made in much greater numbers, several of the very few VMS-82 lathes in existence were converted to cut lacquer, using VMS-80 parts, which were still more or less obtainable. When converted, a VMS-82 essentially became a VMS-80, with very few differences.

     

    Scott Hull inspecting and replacing the cutting stylus on an SX-74 cutter head, using the special microscope provided by Neumann for this purpose. Courtesy of Scott Hull.

    Scott Hull inspecting and replacing the cutting stylus on an SX-74 cutter head, using the special microscope provided by Neumann for this purpose. Courtesy of Scott Hull.

     

    A few more were scrapped, and one was confiscated by the US Federal Government, so in the present day, there are very few original VMS-82 DMM lathes still in operation.

    In regular commercial service, they are all located in Europe, with the largest concentration found in one of Europe’s biggest record pressing plants, in the former Eastern Bloc. In the US, only the Church of Scientology owns VMS-82 DMM lathes, but they only use them for their own internal purposes. The last VMS-82 DMM lathe in commercial use in the US was at Europadisk, up until they folded in 2005.

    Of the ones in Europe, most are operated by pressing plants that have the advantage of being able to recycle the DMM blanks and make new ones, enjoying significant cost savings, in their galvanic plating department. They are not common in independent mastering studios, as the cost advantage is largely lost, or even becomes a disadvantage, if you do not have your own electroplating equipment and need to buy the blanks from someone who does. Of the very few independent studios that have a VMS-82, the one that uses it for audiophile-grade products, where sound quality of the essence, is Pauler Acoustics, in Northeim, Germany (see Issues 147148, 149 and 150) for a discussion of their DMM Dubplate, Vol. 1 DMM disk).

     

    Hendrik Pauler inspecting a DMM disk, cut on the Neumann VMS-82 lathe at Pauler Acoustics in Northeim, Germany. Courtesy of Stockfisch Records.

    Hendrik Pauler inspecting a DMM disk, cut on the Neumann VMS-82 lathe at Pauler Acoustics in Northeim, Germany. Courtesy of Stockfisch Records.

     

    VMS-80 machines are much more common and can be found in active service, in pressing plants and independent mastering facilities on both sides of the pond. A well-known example of a VMS-82 DMM lathe that has been converted to cut lacquer, with an SX-74 cutter head, is Scott Hull’s lathe at Masterdisk, In Peekskill, New York.

     

    Scott Hull using the horizontal microscope on the VMS-82 carriage to inspect the stylus-disk interface. Courtesy of Scott Hull.

    Scott Hull using the horizontal microscope on the VMS-82 carriage to inspect the stylus-disk interface. Courtesy of Scott Hull.

     

    Both the VMS-80 and the VMS-82 were the most highly-automated disk mastering lathes ever to be built. They could be programmed to do spirals (grooves) between songs, start cutting and automatically do the lead-out and lift the cutter head at the end, and even change pitch and depth settings, all from command signals supplied by a digital audio workstation. The operator could largely sit and watch as the machine did the work. On the other hand, they are also used in some of the world’s most respected mastering facilities, by very experienced engineers, who use the lathe’s technical advantages in addition to their own skill.

    An option of a second microscope was also offered, horizontally mounted on the carriage arm, which would focus on the stylus from the side and move in conjunction with it, so the stylus remained in focus along the entire side of the record. This could be also be hooked up to a TV monitor (or perhaps a cinema projector if you had a rich social life) to keep life interesting for the operator (since there wasn’t much left to do anymore, other than combing your hair, being careful not to shed any of your dandruff, hair, or worse on the disk, which might result in clicks and pops, if the debris stays there and is plated over) and to show off to your friends working in more mundane sectors.

    Around that time, Neumann also presented a lathe that could mechanically cut a CD master, in a similar manner to how vinyl record masters were cut. This didn’t ever catch on, as CD masters could also be laser-cut using even more automated machines. Neumann never made anything resembling a lathe again and was eventually bought out by Sennheiser Group in 1991.

    The highly-specialized manufacturing equipment and human resources used to make their mastering lathes are now long gone, never to return.

     

    Scott Hull inspecting the stylus-groove interface while cutting, and holding a blow gun and hose for compressed nitrogen on one hand, in front of his Neumann VMS-82 lathe at Masterdisk. Courtesy of Scott Hull.

    Scott Hull inspecting the stylus/groove interface while cutting, and holding a blow gun and hose for compressed nitrogen in one hand, in front of his Neumann VMS-82 lathe at Masterdisk. Courtesy of Scott Hull.

     

    Postscript: a brief discussion of the geometric parameter differences between cutting lacquer and DMM can be found in Issues 147 through 150 and Issues 125 – 126, for those interested in diving deeper into this subject. These parameters are defined by the design of the cutter head and lathe suspension systems and cannot be altered without modifications. When converting a Neumann VMS-82 DMM lathe to cut lacquer, the geometric parameters are also changed, to suit the different medium.

    Header image: a complete Neumann VMS-82 lathe setup (converted to cut lacquer), with a video monitor at the right, control panel on the left and cutting amplifier rack below the control panel, at Abbey Road Studios, London, UK. Photo courtesy of Miles Showell, freelance mastering engineer based at Abbey Road.

    6 comments on “Around the World in 80 Lathes, Part Three”

    1. When these lathes break down and can no longer be repaired due to age and/or lack of spare parts, it would be more and more difficult to cut new records. And I guess there aren’t too many young engineers entering the profession, given the scarcity of equipment. For regular lacquer disks, how many mothers can be produced from a father, and how many stampers can be produced from a mother before sound quality deteriorates notably ? Do record companies typically keep the metal work after the release of an LP ? For example, is the metal work used to produce the original RCA shaded dogs still available and usable ?

      1. Adrian, there is nothing on a disk recording lathe that cannot be repaired, or even replaced with an upgrade part, as long as there is still a market for new pressings, to justify the expense. Unless one decides to melt the lathe down and make soda cans out of it, worn bearings, worn shafts and failing electronics can all be replaced.
        But, the supply of vintage machines available for sale is indeed drying up as the demand has been skyrocketing, so at present it is not easy to enter this sector, if you do not already have the equipment. This will soon be better, though, as I am currently assembling the first few units of an entirely new disk recording lathe of my own design. Since I had been making pretty much every part that goes on a lathe, to keep the vintage machines running, the next logical step was to make them all at once
        and assemble them into a new machine.
        In the present day, pressing runs are very limited, so even the best-selling records are rarely pressed in over 10000 copies. That same number would have been a minimum order in the 1960s. So, it is not a common practice to produce multiple mothers from a father, although it can be done. There are very many factors that come into play when it comes to how many iterations of the plating process can occur prior to the onset of objectionable side-effects and one of the major ones is the speed of production. Slower is generally better, but takes too long and increases the cost. The common practice is to produce multiple stampers from a mother, but I wouldn’t think that there are many albums (or any at all) nowadays that reach such high volumes of production as to reach the limit of how many stampers can be produced from a single mother. In a good facility, it would probably be over 10. Most of the largest pressing runs nowadays would be more than satisfied with 3-4 stampers.
        The metalwork is typically melted into soda cans soon after production, unless a repress is expected. In that case, only the mothers are kept. Metal mothers do deteriorate over time, especially when not stored properly. I doubt many record labels kept their mothers in climate controlled vaults under archival storage conditions, so it is unlikely that original metalwork is still available in most cases. In the current short-sighted state of the industry, if a pressing plant would charge an extra $10 to deliver the metal mother to the client, the client would most likely prefer to save the $10… Climate controlled vault? In the wise words of Danny DeVito: “Fuggetaboutit!”

    2. I have been thinking whether it is possible to avoid using digital delay line even in the absence of a machine with preview head. I wonder if it is possible to use two playback tape machines synchronised with time code. First, make two copies of the production master simultaneously, and adding time code to each, with one being delayed by however much time the lathe needs. When cutting the lacquer, the signal from one machine is fed into the control mechanism, and the main signal, delayed and synchronised to the first by time code, is fed into the cutter head. Plenty of tape machines have time code installed, so it should not be difficult to do.

      1. Adrian, I assume this would be possible, technically, although I am not aware of this ever having been done. By the time you get two identical machines, calibrate them both, copy the tape, sync them up, and so on, you could just buy a preview head tape machine, or convert one. Conversions of normal rec/repro machines to preview head machines are not that uncommon. As long as you start with a tape machine that is big enough, all that is needed is a modified head block, a few extra rollers on a plate, and an extra set of playback electronics. The tricky part is not the technical implementation (for me at least, with a fully equipped precision machine shop in-house), but the cost of making the parts
        required.

          1. Yes, it will, with absolute certainty. All the preview head tape machines ever made had worse W&F performance than the same machine with the tape not threaded around the rollers, or the rec/repro version of the same model. But the same or worse can be expected of two tape transports synced via timecode. So, when the goal is the ultimate performance that can be achieved, the only viable solution is to not use any pitch/groove depth automation, in which case, no preview signal is required. You can then use a normal rec/repro tape machine, or even record direct-to-disk, straight from a stereo pair or microphone preamplifiers, or a mixing desk if multiple microphones are required.

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