Quick Checklist

Read before every cut. It follows the order of the job and points into the rest of the sheet.

• Before you cut
• Set up the lathe
• Cut
• Finish and send

Before you cut

• Premaster: one vinyl master per side with tracklist, exact times, known flaws marked and the plant named. See Part 1, Step 6
• Side times: agree the running time of each side with the cutting engineer. Longer sides lower the level you can cut. See Part 1, Side Length and Level
• Phase: polarity correct and bass in phase and centred. See Part 1, Step 5
• Side ending and spares: agree the side ending (lead out, locked groove or eccentric groove) and whether to cut a spare of each side
• Reference lacquer: cut one when the client asks or the material is high risk. Agree it before the final lacquers are cut
• Blank: inspected and handled by the edges only. See Part 2, Prepare the lacquer

Set up the lathe

• Calibration: drive level, disc diameters, pitch pointers and depth checked. See Part 2, Calibrating the Lathe
• Stylus: handled by the heater wires only, heat set from the chip behaviour and groove wall sheen on a short unmodulated test groove, walls checked under the microscope
• Lathe: vacuum on, chip removal clear
• Speed: 33 1/3 rpm or 45 rpm to match the plan for the side. At 33 1/3 rpm one revolution takes 1.8 seconds
• Diameters: start, modulation start and closing diameter set for the disc size and checked against your lathe manual and the plant. Boden’s figures are in Standards, Disc dimensions
• Spirals between tracks: 16 to 32 LPI (about 0.63 to 1.26 lines per mm), as Boden gives them. Band size comes from the running time, see Part 1, Side Length and Level
• Template: pitch, land and initial groove width entered for the job
• Signal path: advance path matches the program path, elliptical filter in as planned
• Level: 7 cm/s lateral at 1 kHz is zero level. Albums are cut about 2 to 3 dB above it and 45 rpm singles about 4 to 5 dB above. The cutting engineer sets the final level

Cut

• Test cut: if the material has trouble spots, cut those passages first and check them. See Part 2, Test cut
• Watch: velocity, groove width, land, excursion, phase, head temperature and head current against the limits of your lathe, head and amplifier
• Lead in, spirals, lead out: Boden keeps the pitch under 200 LPI for 2 to 3 seconds around each of them. Lead out one full revolution
• Side ending: cut the agreed ending. See Part 2, Side ending

Finish and send

• Microscope: spot check every disc for overcuts, lift outs and correct depth
• Recut: if the microscope or reference shows a fault from the cut, fix the cause and recut with the saved settings
• Master number: scribe it into the lead out area
• Settings: write down every EQ, compressor and lathe setting so the session can be repeated
• Pack: lacquers flat, padded and protected from heat, each side marked, delivery note inside
• Send: tracked shipping, tell the plant and the client it is on the way, keep a copy of the paperwork
• After the cut: approve or reject the test pressing in writing, then archive the files and notes. See Part 3

Start Here: The Big Picture

Read this first. It shows the whole path from your premaster to pressed vinyl records, and who does what at each step of lacquer cutting and pressing.

• The whole chain in one view
• Who does what
• What makes vinyl different from digital
• How to read this sheet

The whole chain in one view

• Step 1, premaster: you prepare the audio for vinyl and agree the plan with the cutting engineer
• Step 2, lacquer cut: a heated sapphire stylus cuts the groove into a lacquer coated aluminum disc on a lathe. The lacquer is the master. There is one lacquer per side. The lacquer step cannot be redone cheaply. A mistake there repeats in every record
• Step 3, reference lacquer or test cut: a check before the final cut. Changes in level and EQ (equalizer) can still be made
• Step 4, plating: the lacquer is coated with metal and a nickel copy (the metal master, also called the father) is grown on it, then a positive mother, then the stampers
• Step 5, test pressing: a pressing from the finished stampers that you check and approve
• Step 6, pressing: vinyl heated between two stampers with labels, cooled, trimmed, inspected, sleeved

Who does what

• You (mastering engineer): prepare a vinyl specific premaster. Level, bass, highs, sequence and timings
• Cutting engineer: sets groove spacing, depth, level, filters and stylus heat on the lathe. Level on the disc is decided here, not in your file
• Pressing plant: plating, stampers, pressing, quality control. Send the lacquers there, and tell the plant they are coming

What makes vinyl different from digital

• The groove has physical limits. Too much bass, too wide stereo in the bass, too bright highs, or too long a side forces the cutting engineer to turn the level down or narrow the sound
• It is a trade: loudness, bass, stereo width and playing time compete for the same groove space
• You cannot make a vinyl record louder by making the file louder. The cut level is chosen by the cutting engineer
• Sound quality falls toward the centre of the record because the groove passes the needle more slowly there

How to read this sheet

• Process edition: this sheet gives the order of the work, what to check and what to do when something goes wrong. Its figures come from the books and the SimuLathe CUT manual, credited where they appear. Settings differ in every cutting room, so check every figure against your own equipment
• Check your own equipment first: your lathe’s manual and the ratings of your cutterhead, amplifier and breakers always come first. Use this sheet at your own risk
• Where to find values: take them from your lathe manual, your cutterhead and amplifier ratings, your own cutting room routine, and the cutting engineer and plant
• General practice: groups marked (general practice) describe common cutting room routine. Confirm them against your own routine

Part 1: The Premaster for Vinyl, Step by Step

Read when you prepare a premaster for vinyl. Follow the steps in order, from the first talk with the cutting engineer to approving the reference.

• Step 1, talk to the cutting engineer and the plant first
• Step 2, plan the sides
• Step 3, sequence for the groove
• Step 4, check the audio against the groove limits
• Step 5, check phase and polarity
• Step 6, deliver the premaster
• Step 7, approve the reference (when one is cut)

Step 1, talk to the cutting engineer and the plant first

• Agree format and speed, how many sides, and which tracks go on which side
• Ask who handles de-essing and high frequency limiting. Katz says the cutting engineer usually narrows the stereo image in the low end to protect the groove, and limits the highs to protect the head
• Ask which plant gets the lacquers, and tell the plant they are coming
• Do not rely on one file for every format. Boden says the cutting engineer should get uniform material in the correct order, with exact times and shipping instructions

Step 2, plan the sides

• Longer running time forces a finer pitch (more lines per inch), which lowers the level you can cut
• Katz says you cannot change the absolute level of a vinyl record. What matters is side length, especially with heavy bass. Longer sides almost always cost level, stereo separation or bass
• Boden says running time, treble, bass, type of music, amount of vertical information and the producer’s taste are weighed to decide the level
• With long play times, keep both sides at similar running times so a 12 inch release stays consistent
• Give exact times for each selection. A running total of the times also helps the cutting engineer
• See Part 1, Side Length and Level for the method

Step 3, sequence for the groove

• Vinyl needs two sequences, one per side, and the masters cannot be finished without them. Cutting is a one shot job with no undo, so every change of mind costs money
• Put the tracks with the most high frequency energy toward the outside and the calmer ones toward the inside
• Boden says an upbeat, high energy track with strong highs can cause trouble near the inner diameter. A calmer track often suits the end of a side
• Why: groove speed falls toward the inside (see Background, Speed, diameter and the inner groove)
• On a 7 inch or 10 inch side, steer clients away from putting saturated hi hats, distorted guitars or bright vocals on the last track, since inner diameter loss is worse on small sizes
• Warn the cutting engineer about abrupt endings and butt spliced segues

Step 4, check the audio against the groove limits

• Level: a very high cut level causes mistracking and overcuts. A very low level raises the pressing noise compared to the music
• Bass: heavy bass takes a lot of groove space and may force a lower level or a shorter side. Details are in Mastering for Vinyl, Bass. Ask the cutting engineer below which frequency they make the bass mono, and where they limit the highs
• Elliptical equalizer: keep it off, or at its lowest crossover frequency, to keep the stereo image of the master. Go higher only if the microscope shows severe vertical tracking or near lift on the preview pass
• Highs and sibilance: loud or sustained treble can damage the cutterhead, and sibilance is the classic tracing problem. De-essing or a lower cut level is the fix. Details are in Mastering for Vinyl, Highs and sibilance
• High frequencies (general practice): the cutting console’s high frequency limiter starts to act from about 15 to 16 kHz to protect the cutterhead. Do not roll off your premaster there. With high sample rate material, a filter at 19 kHz keeps energy outside hearing from reaching the head. Do not equalize for the RIAA curve. The lathe applies it

Step 5, check phase and polarity

• Out of phase low frequencies are the main cause of vertical groove movement, lift out and a groove that cannot be cut
• Use a Lissajous (X and Y) display: it shows mono or stereo, how much stereo information, and how much is out of phase
• Low frequency material that is more than 90 degrees but less than 270 degrees out of phase is what the elliptical filter deals with. Too much filtering changes the sound
• Keep stereo separation as wide as the material allows. Cutting engineers prefer wide separation, but material with a lot of out of phase content is hard to cut
• Polarity: a master that is 180 degrees out of phase can be corrected with the phase reverse switch on the cutting console. Check your master’s polarity before you send it

Step 6, deliver the premaster

• Ask the cutting engineer for the file format and sample rate they want
• Typical default (general practice): uncompressed WAV or AIFF at 24 bit, 96 kHz or the native project rate of 44.1 or 48 kHz. Do not upsample lower resolution files
• Name files by side and track number (for example B2), or send one file per side (A, B, C, D)
• Zip the folder or include an MD5 checksum (a file fingerprint that proves the file arrived intact)
• Add a tracklist as PDF or TXT, and the catalogue number
• Give exact times for each selection. Say which tracks are on which side
• Mark every known flaw: distortion, odd channel balance, sudden peaks, edits and abrupt endings
• Say whether the source is already mastered, and which plant receives the lacquers
• Give the master numbers to scribe and the shipping instructions for the lacquers

Step 7, approve the reference (when one is cut)

• A reference lacquer is a direct cut disc used for audition, like a proof photograph. Level and EQ can still change before the final lacquers
• Listen for the problems in the Troubleshooting section: inner groove distortion, sibilance, pre echo, level, channel balance
• Approve before the final lacquers are cut

Part 1: Mastering for Vinyl

Read when you do vinyl mastering: how it differs from a digital master, dynamic range, comparing levels, bass, highs, phase and sequence.

• How a vinyl master differs from a digital master
• Dynamic range
• Level on the disc
• Bass
• Highs and sibilance
• Stereo and phase
• Sequence and spreads
• What to deliver

How a vinyl master differs from a digital master

• A vinyl master is a separate master from the CD or online master, because the sequence is two sides. It is often made at a lower level with less compression and limiting
• Ceiling: digital stops at 0 dBFS (decibels relative to full scale). Vinyl stops where the groove physics stops: bass swing, high frequency speed, phase and side length
• Loudness: you cannot make the record louder by making the file louder. The cutting engineer sets the level on the disc
• Playing time and loudness compete: longer sides lose level
• Bass and stereo width are narrowed at the cut, and highs are limited to protect the cutterhead. The cutting engineer does this, not you
• Quality changes across a side: highs suffer toward the inner diameter, so sequence matters
• Cutting is a one shot job with no undo, unlike a workstation. Settings must be repeatable, so they are written down

Dynamic range

• A lacquer master has about 15 to 20 dB better dynamic range than the pressed record
• Katz says vinyl and pre-1990 CDs had higher short term peak to average ratios than heavily limited modern material
• Owsinski advises keeping limiting to about 2 to 3 dB at most, and possibly less for vinyl. The output level for a record may also sit well below the CD level
• Lower disc level fits more time on a side but lowers the signal to noise ratio
• A loud peak, heavy bass or out of phase content can make the stylus cut all the way down to the aluminum base

Level on the disc

• On disc, level is groove velocity against a 7 cm/s lateral reference at 1 kHz (see Level reference), not an RMS (average level) or LUFS (loudness units relative to full scale) figure. Ask the cutting engineer what level they need
• File level does not equal disc level: a file or tape level 6 dB above its reference does not mean the disc is 6 dB above disc zero
• Boden says the cutting engineer weighs total running time, treble, bass, type of music, vertical information and the artist’s taste before setting level. Too much level causes mistracking. Too little raises pressing noise relative to the music
• Loud, dense material needs shorter sides. Longer sides lower the volume

Bass

• Heavy bass uses a lot of groove space and can force a lower level or a shorter side
• Keep bass centred and in phase. The cutting engineer narrows stereo separation in the low end and may use the elliptical filter
• Low frequency content in one channel only, or out of phase, is what drives excessive lateral and vertical movement
• Elliptical crossover frequencies: Owsinski lists 250, 150, 70 and 30 Hz. Ask the cutting engineer what their unit offers and what they use

Highs and sibilance

• Sustained or loud treble, boosted by the RIAA pre-emphasis, can damage the cutterhead or overload the cutting amp
• The cutting engineer also limits the highs to keep the cutterhead safe
• Sibilance sits between about 3 and 10 kHz and comes from heavy compression, mic technique and mic choice. A de-esser compresses a narrow band there
• The cutting engineer de-esses or cuts at a lower level. Sawtooth waves and muted trumpets cause the same trouble
• Do not apply RIAA equalization yourself. The lathe does it

Stereo and phase

• Large out of phase information can lift the stylus off the disc, which makes the record skip

Sequence and spreads

• Vinyl needs two sequences, one per side. The artist and producer decide them before mastering. The mastering engineer must know them before the job is finished
• The gap between songs is called the spread. It sets the pace and can follow the tempo of the song before it
• On the disc the gap between tracks is a spiral, cut with wide groove spacing so it is visible
• Keep both sides at similar running times

What to deliver

• A separate vinyl master per side, with tracklist and exact times
• Everything else on the delivery list is in Part 1, Step 6, deliver the premaster
• Document the session so it can be repeated later

Part 1: Side Length and Level

Read when you plan the sides of your vinyl records: minutes per side, level and pitch.

• Running time
• Pitch from running time (Boden formula)
• Level reference

Running time

• Boden says running time sets the lathe pitch. The longer the side, the more lines per inch are needed, and the finer the groove spacing
• Boden says sides between ten and thirty minutes all have to fit in the same recording area of about 556 square centimeters
• Katz says longer sides are possible, but at a cost in level, separation or bass
• Ask the cutting engineer and plant for the running time that fits your side and your material

Pitch from running time (Boden formula)

• Lines per mm = running time (minutes as a decimal) x rpm / band width (mm). Multiply by 25.4 to get LPI. Boden calls the band width “radius”: the distance from modulation start to modulation end. His album example uses 76 mm. From Boden’s 12 inch diameters (modulated groove starts at 292.1 mm, minimum inside diameter 120.7 mm) the full band is (292.1 – 120.7) / 2 = 85.7 mm, so use the real band of the side
• Running time at a given pitch = band width (mm) x lines per mm / rpm. At 11.8 lines per mm (300 LPI) that is 85.7 x 11.8 / 33.3, about 30 minutes
• Use the real band width of the side from your disc diameters, not a rounded figure
• The formula gives an average pitch for planning disc space. The pitch the lathe actually uses comes from the template or the pitch controller
• At 33 1/3 rpm one revolution takes 1.8 seconds. A 12 minute side is about 400 revolutions, a 20 minute side about 666 and a 28 minute side about 933

Level reference

• Zero level on disc is 7 cm/s lateral at 1 kHz
• Albums are cut about 2 to 3 dB above this, and 45 rpm singles about 4 to 5 dB above. These are ballpark figures. The cutting engineer decides how far
• Producers most often ask the cutting engineer for more volume and more bass, but more of one can rule out more of the other

Part 2: The Cutting Room

Read when you want to know the tools of lacquer cutting: the lathe, console, microscope, lacquer and stylus.

• The lathe, overview
• Lathe parts, A to Z
• Cutting amplifiers and cutterheads, in detail
• The cutting console
• Low frequency crossover (elliptical equalizer, LFX or EE)
• Oscilloscope and microscope
• The lacquer
• The stylus

The lathe, overview

• Main parts: turntable, cutterhead, carriage on a leadscrew, pitch and depth controllers, cutting amplifiers, stylus heater, microscope and chip removal. Details for each are in the next two groups
• Signal flow: the console output feeds the cutting amplifiers, which drive the cutterhead. A copy of the signal, the advance (preview) signal, reaches the pitch and depth controllers ahead of the program so the lathe has time to react

• Pitch and depth work together: pitch follows mainly the sum signal (L plus R) and depth follows mainly the difference signal (L minus R). Both mostly care about frequencies below about 1500 Hz
• Pitch and depth interlock: more depth means fewer lines per inch, and more lines per inch means less depth. Deeper grooves use up the land between grooves, so the pitch has to open up
• Controller types: pitch and depth units differ from lathe to lathe, and some are very sophisticated. Boden calls them computers of various kinds. Newer designs exist (see Pitch controller, newer designs)
• Common lathes: Neumann (VMS 70, VMS 80 and VMS 82) and Scully
• Availability: in 2017 Owsinski wrote that no lathes were being manufactured, and that Scully and Neumann were the most desirable. Check the current situation

Lathe parts, A to Z

• Carriage: carries the head on a leadscrew. The carriage speed sets the pitch: the slower it moves, the more lines per inch. A meter shows LPI (lines per inch)
• Chip removal (swarf): the chip is the thread of lacquer cut away. A vacuum tube behind the cutterhead pulls it into a collector so it does not tangle
• Control section: shows turntable speed and cutting pitch (the LPI meter) and holds the lathe function controls
• Cutterhead: an electromagnet driven by the cutting amplifier that moves the stylus. Neumann SX 74 and the Westrex heads are two classic types. Construction is under Cutting amplifiers and cutterheads, in detail
• Cutterhead protection: circuit breakers cut the drive when the head gets too hot or the head current gets too high. SimuLathe estimates 200 degrees Celsius and 1.5 amperes, only a rough estimate because every cutting room differs, so use the ratings of your own head and amplifier. Above 35 cm/s a head starts to heat disproportionately. Never use the plugin’s virtual breaker instead of the real ones
• Cutting amplifiers: the head is driven by amplifiers of roughly 1,000 to 3,500 watts or more. Energy above about 5 kHz takes a great deal of power to cut, so a fault can destroy the lacquer and perhaps the stylus or the cutterhead
• Depth controller (variable depth unit): keeps the groove at least 25 micrometers wide (a playback stylus is about 18 micrometers) and under about 152 to 178 micrometers, so the cutting stylus does not jam into the aluminum
• Leadscrew: the carriage rides on it. Pitch is changed by speeding up or slowing the motor that turns it
• Microscope light: the Neumann AM 32, VMS 66 and VMS 70 use a Leitz microscope with a special B9d bulb that runs hot
• Other lathe controls: stylus heat, depth of cut, start and end diameters, turntable speed, spiral and band size
• Pitch controller, newer designs: follow the Studer Kaufmann pitch98 design from 1998. They control the preview signal in real time, let the operator set land and depth as on the Neumann VMS 80 and 82, and read lead in and lead out from a bank of microswitches on the lathe
• Pitch controller (variable pitch unit): the part that sets groove spacing. It reads the advance signal and drives the motor that turns the leadscrew, so the carriage moves faster or slower across the disc. Its job is to stop neighbouring grooves from banging into each other (overcut) while keeping the pitch high enough that no disc space is wasted
• Preview system: the program is delayed so the engineer can hear and fix a problem before it reaches the lacquer. Originally a tape machine with separate preview and program heads and a long tape path, now a digital delay
• Stylus heater: nichrome wires carry heater current to the stylus. The heat is set with a rheostat (variable resistor) on the lathe
• Turntable: forged aluminum, vacuum holds the lacquer flat so it cannot slip. Slippage would cause speed variation. It has a disc size selector and vacuum holes. The original Neumann bearing unit is oil filled

Cutting amplifiers and cutterheads, in detail

• Cutterhead construction: two drive coils (left and right), the stylus shank and the stylus tip. Each moves at a different velocity, so excursion seen in the microscope does not give true loudness
• Cutterhead overload (general practice): too much high frequency energy can overload the drive coils and burn out the helium cooled suspension wires of a head such as the SX 74. Check the cooling and ratings in your head’s manual
• Cutterhead service parts: drive coils, feedback coils, springs, a V spring and the torque tube. Common Neumann heads are the SX 68, SX 74 and SX 84
• Neumann rack boards: bus card (SAL 74), encoder card with the RIAA parts (SAB 74), feedback card, relay board (SEL 74) and power supply
• Rack wear points: relays wear out, and parts of the feedback amplifier are often out of specification. Older SAL 74 units used transformers in the feedback amplifier

The cutting console

• Mono and stereo switch, master fader, level controls, phase reverse switch, monitor select section, echo send and return
• Compressors, limiters and several sets of EQ in A and B routing. The cutting engineer can pre set the next track and switch during the spiral
• Same processing on the program and advance paths, or the lathe computers get false information
• Oscillator for tones, oscilloscope and phase correlation meter
• Metering: VU (volume unit) and peak meters (PPM, peak program meter). Use both. Disc line level is 1.55 V, which is 6 dB over 0 dBm (0.775 V). 0 VU is minus 6 dB on the peak scale
• Outputs for tape copies that match the cut so all formats sound alike
• Settings sheet: the cutting engineer records every EQ, compressor, lathe setting and diameter so a session can be repeated later

Low frequency crossover (elliptical equalizer, LFX or EE)

• Used when low frequency material is between 90 and 270 degrees out of phase. It removes excessive vertical groove lifts
• Out of phase material or bass on one side only is what drives excessive lateral movement, and this unit sends it to the centre
• It works by letting the stronger out of phase component cancel the weaker one on the other channel. The result is mono at low frequencies
• Too much changes the sound and narrows the stereo image. Use carefully
• Check which crossover frequencies your unit offers and use the lowest that does the job

Oscilloscope and microscope

• Oscilloscope: a Lissajous (X and Y) pattern shows mono or stereo, amount of stereo, and out of phase content. Also used to align the azimuth of the playback tape machine
• Microscope: about 200 times magnification, with its own light. Each groove shows as three bright lines. The land between is black
• Check groove size with the reticle. Look for too much bass, treble or level, overcuts, lift outs, correct depth
• Check stylus heat and stylus condition by looking at the groove walls
• A smaller, separate microscope is used when fitting the stylus into the head

The lacquer

• A thin nitrocellulose lacquer on an aluminum disc. Most records start from one
• The lacquer is oversized: a 12 inch record is cut on a 14 inch disc so the playing area is not damaged when it is handled
• Only one side of each blank is guaranteed flawless
• A reference lacquer (ref, acetate) is the same soft material. It can be played only five or six times before quality falls. The master lacquer can never be played after it is cut
• Heat during shipping can cause oils to bleed or damage the lacquer. The plant will reject such discs and ask you to recut them

The stylus

• Material: synthetic sapphire (ruby is also used)
• Handling: never touch it with bare fingers. Hold it by the heater wires, or with non magnetic tweezers
• Burnishing facets: the tip has two blunt facets, about 3.8 to 5.1 micrometers wide, that wipe the groove wall smooth, which cuts noise. Wider facets last longer but weaken the highs. Narrower facets keep the highs but wear faster
• Heat: nichrome wire heats the stylus. Heat lowers noise, improves the highs and makes the stylus last longer
• Setting the heat: Boden sets it where a quiet groove has the least hiss, checked at the inner and outer diameter and averaged, and rechecks with each new stylus or batch of lacquers. The Neptune method, from the chip behaviour and groove wall sheen, is in Part 2, Set up the stylus
• Too much or too little heat: too much scores lines into the groove wall. Too little leaves the wall dull, grainy and grey
• When to replace it: the cut loses its shine and smoothness, the tip chips, noise rises or the highs fall away. Boden’s limits are a tip radius over 6.4 micrometers or a bottom line over 12.7 micrometers. He says edge wear shows after about 10 hours of cutting and the tip radius is too large after about 20 hours. Wear shows on the groove walls well before the stylus fails, so judge by groove wall quality, not only by hours of cutting

Part 2: Calibrating the Lathe

Read when you set up or check a lathe: drive level, diameters, pitch system and depth.

• How to read this part
• Step 1, drive level of the cutting amplifier
• Step 2, disc diameters
• Step 3, pitch system
• Step 4, depth, preview and track marks
• How far off is too far

How to read this part

• Source: the SimuLathe CUT manual (Tokyo Dawn Labs). The plugin simulates a lathe, so its checklist is written to match the plugin to a real lathe. The same checks show whether a real lathe is in calibration
• The manual of your own lathe decides how to adjust the hardware. SimuLathe only says “as described in the manual”
• Pitch system: the unit that sets groove spacing (pitch) and depth from the advance signal

Step 1, drive level of the cutting amplifier

• Level is expressed as the peak of the lateral velocity. For 45 degree stereo: lateral = (left + right) / 2 and vertical = (left minus right) / 2
• Reference tone: a 1 kHz sine at the room’s analog reference level, in most rooms 0 VU = 1.23 V
• Test record velocity: most often 7 cm/s lateral (NAB, the National Association of Broadcasters, or the Ultimate Analog Test Record). The sleeve value does not always give the peak of the 1 kHz lateral sine. If the pitch system pointers disagree (see Step 3), adjust the value
• Your lathe may run at a different cm/s than the test record sleeve says, depending on your routine
• Also calibrate with 100 Hz at the typical cutting level of the room, because the reference level is far below a typical cutting level. Start with 1 kHz, then rely more on 100 Hz if the pickup is stable
• Do not turn microscope excursion into cm/s and trust it. Coils, shank, tip and groove edge move at different velocities, so the result misjudges loudness

Step 2, disc diameters

• Check the inner and outer diameter micro-switches for 7, 10 and 12 inch against the standard positions
• If a switch reads wrong, record its real value. If the switches are right but the whole scale has shifted, reposition the scale exactly

Step 3, pitch system

• Pitch gain: dial in a base pitch of 10 lines per mm on the lathe, which is a groove width of 100 micrometers with zero land, so the grooves just touch. Check zero land under the microscope and trust the microscope. The lines per mm scale on the lathe can be off
• Diameter test with no audio: run the plugin and the lathe in parallel and compare the position pointers over the whole side. Expect them to match. If they do not, the pitch gain is off, so calibrate it first
• Lateral gain: feed a constant mono sine at typical cutting level, 100 Hz or lower. Run the diameter test. The pointers should match. If not, the pitch system input gain or the lateral gain setting on its programmer is off
• Vertical gain: calibrate as described in the lathe manual
• Lateral gain caused by vertical gain: play a steady out of phase 140 Hz sine 10 dB below your usual mono cutting level, then run the diameter test and compare the pointers
• Best fix: calibrate the lathe. The other option is a trim offset in the plugin, which only moves the error into the software

Step 4, depth, preview and track marks

• Minimum depth (groove width): Neumann VMS 66 and 70 use 50 micrometers. Modern lathes typically 55 micrometers. VMS 80: equal to the initial width setting, less the economy value if used. Check your lathe manual
• Preview lookahead: VMS 66 and 70 use 6/10 of a revolution. VMS 80 uses 1/2 of a revolution. Check your lathe manual
• Track marks: the wider groove spacing the pitch system cuts at the start of each track, so the tracks can be seen on the disc. They change only the pitch, not the audio. Marker Length sets how long a mark runs: typical range 0.3 to 2 seconds, typical value 1 second. SimuLathe’s own default is 2 seconds. Marker Pitch sets the groove spacing during a mark: the manual gives a typical range of 0.8 to 1.15 mm and a typical value of 0.5 mm. Greater values give longer, wider and more visible marks. Both should match the real lathe that cuts the master (SimuLathe CUT manual)

How far off is too far

• Trim offsets above 2 to 3 dB point to a procedure problem. Fix the procedure first
• Aim for one of the two pitch trim offsets to sit at or very near 0 dB
• If both offsets drift the same way (for example minus 4 dB and minus 4.5 dB), the cm/s value is wrong, not the pitch gains. Correct the cm/s value first
• Check that the excursion in the lathe microscope matches the plugin’s virtual microscope as closely as possible

Part 2: Cutting a Lacquer, Step by Step

Read when you do the lacquer cutting yourself. Follow the steps in order.

• Before the session
• Set up the stylus
• Prepare the lacquer (general practice)
• Set up the lathe
• Set the level
• Test cut (when the material calls for it)
• Cut
• Side ending (general practice)
• Finish the lacquer
• Spares and recuts (general practice)
• Pack and send (general practice)

Before the session

• Get the premaster, tracklist, timings per side, catalogue number and plant name
• Listen through, note any peaks, edits and abrupt endings, and decide the level, EQ, filters and pitch
• Work out the pitch from the side length (see Part 1, Side Length and Level)
• Settings sheet: have it ready. Boden: record every EQ, compressor, echo and lathe setting, plus the ending diameter and the band size, so a session can be repeated months or years later

Set up the stylus

• Handle the stylus only by its heater wires, or with non magnetic tweezers. Never touch it with bare fingers
• Mount it using the small microscope
• Starting current: take it from the stylus maker and your lathe manual. It depends on the stylus shank mass and age
• Neptune method: set the heat from the chip (swarf) behaviour and the groove wall sheen under the microscope. Cut a short unmodulated test groove and check the walls are mirror smooth, with no tearing or micro fractures. A listening test alone can be masked by monitoring chain noise
• Boden’s method: set the heat where a quiet groove has the least hiss, checked at both the inner and outer diameter and averaged. Do this with each new stylus or batch of lacquers
• Check the groove walls under the microscope. Too much heat shows as scoring lines. Too little shows as grey, grainy walls
• Change the stylus when the groove walls under the microscope show scoring lines, chipping or micro fractures instead of a mirror sheen, or when hiss rises, most of all near the inner diameter. Do not rely on an hour or side counter alone

Prepare the lacquer (general practice)

• Keep blanks flat, in their packaging and away from heat until the session. The coating is soft
• Handle the blank by the edge and the centre hole only. Never touch the coated surface
• Inspect the blank before it goes on the turntable: look for scratches, dents, dust, fingerprints and coating flaws. A flawed blank is not cut
• Check the blank is the right size for the planned side before setting the diameters
• Remove loose dust without touching the surface, using the method your cutting room already uses
• Warm up: whether and how long to warm up the lathe and amplifiers depends on the lathe make and model and on the room and climate. Follow your lathe’s manual and your own routine

Set up the lathe

• Lacquer on the turntable, vacuum on so it cannot slip. Slippage would show up as speed variation in the record
• Check chip removal. The vacuum sucks the chip away through a tube behind the cutterhead
• Set turntable speed and disc size
• Set the start diameter and the closing diameter for the disc size
• Set the size of the spirals (bands) between tracks
• Set the variable pitch and depth unit. On newer controllers the operator sets land and depth, as on the Neumann VMS 80 and 82
• Signal path to the cutterhead: the advance (preview) path must have the same level and processing as the program path
• Switch in the elliptical filter and the other protection filters as planned

Set the level

• Reference level: 7 cm/s lateral at 1 kHz. Albums are cut about 2 to 3 dB above it and 45 rpm singles about 4 to 5 dB above. The cutting engineer sets the cutting level for the material and the side length
• Use peak meters as well as VU. Know where 0 VU sits in your room
• Watch the vectorscope for phase and the console peak meters during the cut

Test cut (when the material calls for it)

• Trouble spots to consider: heavy or out of phase bass, loud or sustained highs and sibilance, the densest passage near the inner diameter, and abrupt endings or segues
• Check on the lathe: the SimuLathe velocity heat map, groove width, land and excursion against your template, overcuts and lift outs under the microscope, the groove walls for stylus heat, and head temperature and current
• Check by ear on the test cut: inner groove distortion, sibilance, pre echo, level and channel balance
• If a problem shows: use the matching entry in Troubleshooting to change level, bass handling, high frequency limiting, pitch or heat before the final cut

Cut

• Lead in: the lathe cuts the first groove. Boden says to keep the pitch under 200 LPI until 2 to 3 seconds after the lead in spiral ends
• Program: cut each track. Cut a spiral of 16 to 32 LPI between tracks, and keep the pitch under 200 LPI for 2 to 3 seconds on either side
• Program pitch comes from the template or the pitch controller. The wide spacing figures apply only to the seconds around the lead in, spirals and lead out
• Each lacquer needs one continuous groove with land beside it. The groove must never cross or run into itself in a way that weakens the groove wall
• Lead out: one complete revolution at the lead out pitch
• Side ending: see the Side ending group below. The standard ending is the lead out
• The lathe order of buttons depends on the machine. Use your lathe manual for that

Side ending (general practice)

• Lead out: the standard ending. The groove spirals away with wide groove spacing into the lead out area
• Locked groove: a closed circular groove at the end of a side. The stylus stays in it and repeats until the tonearm is lifted
• Eccentric groove: a groove that swings off centre in the lead out area so that the tonearm of an automatic player is moved and the player lifts or returns
• Planning: agree the ending with the client and the plant before the session. Check the plant can press the ending the client wants. The ending is cut as a separate step after the last track, so note it on the delivery note

Finish the lacquer

• Spot check each disc through the microscope for overcuts, lift outs and correct depth. Check stylus condition from the groove walls
• Check groove width and depth with the microscope reticle against your template and lathe limits
• Scribe the master number into the lead out area. This matches the labels to the right stampers
• Cut a reference lacquer before the finals when the client asks or the material is high risk. For well prepared material, the production masters can be cut directly from the calibrated preview path and the meters
• Protect the lacquer from heat. Shipping in heat can make the coating bleed and the plant will reject the disc and ask for a recut
• Mark each side clearly and send to the plant

Spares and recuts (general practice)

• Decide before the session whether to cut a spare of each side. A spare costs a lacquer and lathe time. Without one, a failed side means cutting again
• Cut a spare when the job asks for it or the budget includes it
• Recut when the microscope or the reference shows a fault that Troubleshooting places in the cut, or when the plant rejects a lacquer
• Recut with the saved settings sheet and change only what the fault requires, so the recut matches the first cut in everything else
• Label spares and recuts clearly so the plant sends the right lacquer to plating

Pack and send (general practice)

• Lacquers are soft. Do not stack them loose or let anything press on the surface
• Pack each lacquer flat in a clean sleeve, padded so it cannot move or press against another disc
• Protect from heat during shipping. See Finish the lacquer
• Label every disc and sleeve: title, side, speed, master number and catalogue number
• Include a delivery note: client, title, catalogue number, plant, sides and speed, running time per side, master numbers, special notes such as known flaws or the side ending, and your contact details
• Use tracked shipping. Tell the plant and the client that the lacquers are on the way and when they should arrive
• Keep a copy of the delivery note and the tracking number

Part 2: Cutting Safely: Check, Fix, Protect

Read during a cut: what to watch, safe limits, common errors and fixes, and how to protect the cutterhead.

• What to watch while you cut
• Limits to stay inside
• Protect the cutterhead

What to watch while you cut

• Distortion meter (total harmonic distortion, THD): watch the trend on a test cut. With feedback monitoring on it also shows groove self erase from the cutting stylus at high velocity
• Excursion: keep it below the initial groove width of your template. Above that, unstable pickups can skip out of the groove at high cutting level. The SimuLathe excursion limiter has a hidden brickwall threshold at 150 micrometers. Low frequencies drive excursion, and a slight change in the high pass filter can change it a lot
• Groove width: stay inside the range of your lathe and template, and keep it moderate, because very wide grooves can cause problems in later reproduction steps. On DMM (direct metal mastering) the limit is tighter than on lacquer. Width is twice the groove depth because the groove is 90 degrees
• Head current: the breakers engage above the head current rating. SimuLathe estimates about 1.5 amperes on either channel, a rough estimate, so use your own head’s rating
• Head temperature: the breakers engage above the head temperature limit. SimuLathe estimates about 200 degrees Celsius, a rough estimate that differs in every cutting room
• Land: keep at least 5 micrometers between grooves (SimuLathe). Below that it cannot be controlled reliably on hardware. Zero or negative land means the grooves touch or overcut
• Level on disc: 7 cm/s lateral at 1 kHz is zero. Albums are cut about 2 to 3 dB above it and 45 rpm singles about 4 to 5 dB above
• Meters: watch the peak meters as well as VU, and the phase scope
• Microscope: about 200 times magnification. Look for overcuts, lift outs, correct depth and stylus condition. Boden says stylus edge wear shows after about 10 hours of cutting
• Phase correlation: a low reading means vertical stylus movement. Low frequency content more than 90 degrees but less than 270 degrees out of phase needs the elliptical equalizer (Owsinski lists 30, 70, 150 and 250 Hz)
• Pitch: wider groove spacing (fewer lines per inch) uses more disc space. Boden keeps the pitch under 200 LPI for 2 to 3 seconds around the lead in, lead out and spirals, and cuts the spirals themselves at 16 to 32 LPI
• Preview lookahead: 6/10 of a revolution on a VMS 66 or 70, 1/2 of a revolution on a VMS 80. Check your lathe manual
• Stylus: replace by groove wall quality. Boden’s limits are a tip radius over 6.4 micrometers or a bottom line over 12.7 micrometers
• Velocity: above 35 cm/s the head heats disproportionately. Very short peaks of 60 to 70 cm/s and maybe above are not unusual for a very hot cut, but some pickups distort much earlier, especially on longer signals. Keep high velocity regions short and only as loud as needed. SimuLathe’s dynamic low pass fades in between 25 and 35 cm/s

Limits to stay inside

• Excursion: above the initial groove width, an unstable pickup can skip out of the groove at high cutting level
• Groove size: Boden writes that grooves “deeper” than 178 micrometers risk jamming the cutting stylus into the aluminum base and ruining it. He uses depth and width loosely, so stay well inside your template width
• Groove width: stay inside the range your lathe manual gives. SimuLathe warns that very wide grooves on lacquer, or on DMM, are risky for later reproduction steps. DMM is direct metal mastering, cut into a metal blank instead of a lacquer
• Land: below 5 micrometers cannot be controlled reliably on hardware (SimuLathe). Do not plan for zero land if you want no overcuts

Protect the cutterhead

• The ratings of your head and amplifier are in their manuals
• SimuLathe gives rough estimates for when the breakers engage. Every cutting room and head is different, so use the ratings in your head’s manual
• Never replace real circuit breakers with software ones
• Cutting amplifiers are powerful, and high frequency energy takes a great deal of power to cut, so a fault puts the lacquer at risk, and perhaps the stylus or even the cutterhead
• Above 35 cm/s the head starts to heat disproportionately. In extreme cases this can trip the safety circuit breakers
• Very short peaks of 60 to 70 cm/s, and maybe above, are not unusual for a very hot cut. It depends on the condition of the cutting amp and the head. The SimuLathe authors say they are still researching safe values, so there is no proven safe number
• Check the velocity heat map on a test cut before the real cut, and shorten any long high velocity stretch
• Limit the highs: cutting engineers cap high frequency peaks so the head is not overloaded. The limiter acts from about 15 to 16 kHz (general practice)
• A dynamic low pass fades in between 25 and 35 cm/s. SimuLathe’s velocity limiter cuts highs first, and in extreme cases attenuates the whole signal to protect the head
• With high sample rate material, use a filter at 19 kHz to keep frequencies outside hearing from reaching the head
• Bass excess, a loud peak or out of phase material can cut right through the lacquer to the aluminum, which can destroy the lacquer and an expensive stylus. This is why the preview path exists. Cutting does not stop, so every change is made on the fly
• If you limit, keep it to about 2 to 3 dB at most (Owsinski), and possibly less for a vinyl master. The output level for vinyl may sit well below CD

Part 3: After the Cut

Read when the lacquers leave the room: plating, pressing the vinyl records, test pressing and defects.

• Test pressing: what to check
• Approve and archive (general practice)

Test pressing: what to check

• A test pressing is pressed from the finished stampers so it can be checked and approved
• Compare against your reference lacquer and premaster
• Listen for every defect in the Troubleshooting section. Sort each into cut (your side) or plant (vinyl, press, stamper)
• Boden says you can play a metal mother on a turntable, so ticks and swishes may already be in the metal as well as in the vinyl
• Check physical faults by eye: warp, non fill, off centre record, torn or reversed labels, wrong record in the jacket

Approve and archive (general practice)

• Give the plant a clear written answer: approved, or not approved with the faults listed. The plant waits for it before the production run
• If a fault is in the cut, recut and make a new test pressing. If it is in the plant work, send the plant your notes and the fault
• Keep the approval message with the catalogue number
• Archive the premaster files, the settings sheet, the delivery note, the tracking number and your listening notes under the catalogue number

Troubleshooting

Read when something sounds or looks wrong: at the lathe, on the reference, on the test pressing, in calibration, or a cutterhead warning.

• How to use this section
• At the lathe (microscope and meters)
• Heard on the reference lacquer or a test play
• Heard or seen on the test pressing
• Calibration does not match
• Cutterhead warnings

How to use this section

• Find where you notice the problem: at the lathe, on the reference lacquer or test play, on the test pressing, in the calibration, or as a cutterhead warning. Each line gives the cause, the fix and who owns it
• Who owns it matters: cut (you or the cutting engineer) or plant (vinyl, press, stamper)

At the lathe (microscope and meters)

Heard on the reference lacquer or a test play

Heard or seen on the test pressing

Calibration does not match

Cutterhead warnings

Standards

Read when you need the published standards: reference level, speeds, the RIAA curve, disc dimensions and the formulas.

• Reference level and speeds
• RIAA curve (recording side), selected points
• Disc dimensions (Boden, 1981)
• Other numbers
• Formulas

Reference level and speeds

• Zero level on disc: 7 cm/s lateral at 1 kHz
• Speeds: 33 1/3 rpm and 45 rpm. At 33 1/3 rpm one revolution takes 1.8 seconds
• Analog reference level: a 1 kHz sine at the room’s reference level, in most rooms 0 VU = 1.23 V

RIAA curve (recording side), selected points

• 20 Hz -19.3 dB, 50 Hz -17.0 dB, 100 Hz -13.1 dB, 500 Hz -2.6 dB, 1 kHz 0 dB
• 2 kHz +2.6 dB, 5 kHz +8.2 dB, 10 kHz +13.7 dB, 15 kHz +17.2 dB, 20 kHz +19.6 dB
• These are Boden’s values. RIAA is the Recording Industry Association of America. Playback undoes it

Disc dimensions (Boden, 1981)

• 12 inch: start of the outside groove 297.7 mm. Start of modulated groove 292.1 mm. Minimum inside diameter 120.7 mm. Lockout groove diameter 106.4 mm
• 10 inch: start 246.9 mm. Modulated start 241.3 mm. Minimum inside 120.7 mm. Lockout 106.4 mm
• 7 inch: start 172.2 mm. Modulated start 168.4 mm. Minimum inside 108.0 mm. Lockout 98.6 mm
• Unmodulated groove: width 51 to 102 micrometers
• Modulated groove: depth between 25 and 127 micrometers, as Boden lists it. A 90 degree groove is twice as wide as it is deep, so treat his width and depth ranges as loose. Each lacquer must have one continuous groove with adjacent land and no crossing
• Lead in: Boden says to keep the pitch under 200 LPI until 2 to 3 seconds after the lead in spiral ends
• Lead out: one full revolution at the lead out pitch. Keep the pitch under 200 LPI from 2 to 3 seconds before the lead out
• Spirals (gaps between tracks): cut between 16 and 32 LPI, with the pitch under 200 LPI for 2 to 3 seconds on either side

Other numbers

• 1 kHz at 7 cm/s: peak displacement about 11 micrometers, peak to peak about 22 micrometers
• Fixed pitch (old method): Boden gives 225 LPI for a 20 minute side. Pitch is now variable
• Stylus replacement (Boden): tip radius over 6.4 micrometers, bottom line over 12.7 micrometers

Formulas

• Lines per mm = running time (minutes as a decimal) x rpm / band width (mm). Multiply by 25.4 to get LPI
• Running time = band width (mm) x lines per mm / rpm
• Displacement = peak velocity / (2 x pi x frequency)
• Disc diameters and groove sizes: Boden’s figures are in Disc dimensions below. Check them against your lathe manual, the plant and your cutting engineer

Background

Read when you want the reasons: how a groove works, lacquer and plating, pressing, half speed mastering and older methods.

• Two ways to move the stylus
• Why bass is a problem
• Why highs are a problem
• Speed, diameter and the inner groove
• Pitch, depth and land
• Advance (preview) signal
• Lacquer coating
• From lacquer to stamper
• Pressing
• Half speed mastering
• Cutterhead response test (historic)
• Cutting amplifier power history

Two ways to move the stylus

• Lateral: the groove wiggles side to side. Mono records are lateral only
• Vertical: the groove gets deeper and shallower, so it gets wider and narrower
• Stereo (45/45 system, from Westrex): left and right channels are cut on the two groove walls at 45 degrees. Left only gives modulation on one wall, right only on the other wall
• Same signal in both channels (mono, centred): the stylus moves only side to side
• Opposite signal in the two channels (out of phase): the stylus moves only up and down. Equal level out of phase gives a groove that alternates between shallow and narrow, and deep and wide
• Louder in one channel: the groove centre moves toward that side

Why bass is a problem

• Stylus velocity follows the signal level. The groove swing (displacement) is larger as frequency falls
• With the RIAA recording curve applied and the same input level, a 125 Hz tone needs 2.25 times the groove space of a 1 kHz tone, and a 30 Hz tone needs 4 times
• Out of phase bass causes big vertical movement. This can lift the stylus out of the groove (“lift out”) or make a groove impossible to cut and play
• So bass is kept centred (mono) and in phase. The cutting engineer also uses an elliptical filter on the low end (see Part 2, Low frequency crossover)

Why highs are a problem

• The RIAA cutting curve (RIAA is the Recording Industry Association of America) boosts highs a lot when cutting. Bright, loud, sustained highs can overload the cutting amplifier and damage the cutterhead
• A groove that is too fast or complex cannot be traced by the playback stylus. Sibilance (strong s sounds) is the classic case
• Sibilance, sawtooth waves and muted trumpets cause the most trouble. Cutting engineers de-ess or lower the level

Speed, diameter and the inner groove

• 33 1/3 rpm (revolutions per minute) is 1.8 seconds per revolution
• Groove speed is highest at the outside of a side and falls toward the inner end, so the same audio is packed much more densely at the end
• That gives three losses: cutting loss (the stylus erases its own highs), tracing loss (the needle skips detail) and deformation loss (vinyl and lacquer give under pressure). Deformation loss is the biggest
• Automatic corrective EQ toward the inside was tried and given up, with no measurable success
• Fix by sequencing: loud, bright, dense tracks near the start of a side. Quieter and gentler tracks at the end

Pitch, depth and land

• Pitch: how close the grooves are, in lines per inch (LPI), set by how fast the cutterhead moves across the disc. One inch is 25.4 mm. Higher LPI means grooves closer together
• Land: the flat space between two grooves

• Depth and pitch are linked. Deeper groove needs more land, so fewer lines per inch
• Groove width must stay between a minimum the playback stylus can ride in and a maximum that avoids jamming the cutting stylus into the aluminum. Boden uses depth and width loosely
• Overcut: grooves so close that adjacent grooves cut into each other. This is a defect
• Variable pitch and variable depth: the lathe reads the signal ahead of time and spreads the grooves apart for loud bass and narrows them for quiet passages, so no space is wasted
• Every side has to fit in the recording area of the disc

Advance (preview) signal

• The pitch and depth computer needs to see the audio before the cutterhead cuts it. The program audio is delayed so the lathe has time to move
• Old way: a tape machine with two playback heads, a preview head and a program head. Later, digital delay lines. The VMS 80 delay is 1/2 of a revolution
• The preview path must get the same level and EQ as the program path, or the lathe gets false information and spaces the grooves wrong

Lacquer coating

• Coating ingredients: resins for adhesion, pigments for opacity and visibility, plasticizers for softness, solvents to blend

From lacquer to stamper

• The plant inspects each lacquer, then cleans it with mild detergent and distilled water
• Tin (stannous chloride) then silver is applied so the disc is conductive
• Nickel is plated on it in a bath. If plating is too fast, groove echo (pre echo) can result
• The nickel is separated. That is the metal master (father), a negative copy
• A mother (positive) is grown from it. You can play a mother on a turntable
• The mother is cleaned up: de-ticking removes debris, dehorning removes small ridges at the top of the groove wall
• Stampers (negative) are grown from the mother. The stamper gets an exact centre hole and is sanded at the back
• One step processing: stampers made straight from the lacquers, only for short runs because stamper life is limited. More stampers need more lacquers

Pressing

• Vinyl granules are heated into a biscuit. A label goes on each side
• The press closes much like a waffle iron. The vinyl reaches about 150 degrees Celsius under a pressure of about 140 bar
• How completely the vinyl fills the groove depends mostly on pressure, temperature and the vinyl’s texture. A press below operating temperature causes ticks and pops. This is the plant’s side, not the cutting engineer’s or yours
• Water cools the stampers from behind, the press opens, and excess vinyl (flash) is trimmed with a hot knife or a dinker
• Quality control: careful visual inspection, then sleeve, jacket and shrink wrap. Too much heat in the shrink tunnel bows the disc

Half speed mastering

• The lathe and the source both run at half speed (16 2/3 or 22 1/2 rpm). Frequencies are halved, so 10 kHz becomes 5 kHz
• Easier for the cutterhead: lower maximum groove velocities, lower amplifier power, and the high frequency limiting can be bypassed
• Takes twice as long (a 20 minute side takes 40 minutes). Real time monitoring is not possible, so several reference lacquers may be needed

Cutterhead response test (historic)

• Buchman Meyer light pattern: cut a series of tones, each at least 10 revolutions long. A light at 45 degrees shows a pattern whose shape shows the response
• Mostly historic: it is of little use below 1 kHz, and modern dynamic feedback cutterheads are stable and linear

Cutting amplifier power history

• Amplifier power grew from about 10 to 12 watts in the 1950s, to about 75 watts per channel from Neumann in the 1960s, to about 500 watts in the 1970s

Glossary

Read when you meet a vinyl mastering or lacquer cutting term you do not know.

• Cutting and groove terms
• Mastering and plating terms
• Units and measures

Sources

Read to see the books, manuals and pages this Process Cheat Sheet for Cutting Lacquers draws on.

• Books
• Neptune Mastering Studios
• Lathe service specialists
• Plugin manual

Books

• Boden, Larry: Basic Disc Mastering. Larry Boden, 1981. Main authority for this sheet. Analog era, but the physics and glossary still hold. Some details (tape machines, plant list, U.S. addresses) are dated
• Katz, Bob: Mastering Audio: The Art and the Science. Focal Press, 2002. Only a short vinyl note, in Appendix 3. Mostly about CD, so used sparingly
• Owsinski, Bobby: The Mastering Engineer’s Handbook, 4th edition. Bobby Owsinski Media Group, 2016. Chapter 8, Mastering for Vinyl, plus the sequencing notes. Used for cutterhead risk, fixes for intercuts, level and sequencing

Neptune Mastering Studios

• Cutting room routine for stylus heat, side endings, spares, reference lacquers and elliptical equalizer practice

Lathe service specialists

• FLoKaSon: flokason.ch. Swiss lathe service specialists, treated as an expert source. Used to describe lathe hardware parts

Plugin manual

• SimuLathe CUT manual: Tokyo Dawn Labs Knowledge Base. An industry standard plugin, built with working cutting engineers and used in cutting rooms to reduce wasted lacquers. Used for lathe calibration, meters, limits and cutterhead protection. The manual labels its temperature and current limits as rough estimates, not hardware ratings