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Needle-dropNeedle-drop HandbookHandbook byby RichardRichard BriceBrice A complete guide to the history, theory and technology of phonograph records for archivists, collectors and vinylistas 2nd edition PspatialPspatial AudioAudio Frontmatter Needle-drop Handbook i Needle-drop Handbook Needle-drop Handbook Trans∫orm Media Limited Newtown House 38 Newtown Road Liphook, Hampshire. GU30 7DX. Second edition 2021 Ver. 2.0 First published 2020. Ver. 1.0 © Richard Brice 2020, 2021 All rights reserved. No part of this publication may be reproduced in any material form (including photocopying or storing in any medium by electronic means and whether or not transiently or incidentally to some other use of this publication) without the written permission of the copyright holder except in accordance with the provisions of the Copyright, Designs and Patents Act 1988. Application for the copyright holder’s written permission to reproduce any part of this publication should be addressed to the publishers. ii Frontmatter Contents Preface Anyone for damping? An experiment....... Chapter 1 - The long and winding road Side thrust The legacy of the phonograph record The (Removable) Headshell Stereo Lab Better without? Road map Aluminium Chapter 2- The turntable Magnesium Carbon Types of drive Composites Idler drive Wood Belt drive The physics Direct drive Adding spring to the headshell Types of motor The headshell's effect on arm DC motors - part 1 resonance AC motors Headshells conclusion Three speed box Radial (or, linear-tracking) tonearms Speed control with synchronous Active motors Passive DC motors - part 2 Other approaches... Standard speeds for phonograph (gramophone) No side-thrust records "Cut Across Shorty" Stroboscope disc Unipivot tonearms What makes a turntable good? The gimbal bearing Constant speed The Unipivot Platter Torsional Stability Bearing For the archivist? Isolation - resistance to shocks and to acoustic feedback Appendix 1 - Bauer’s simplifications in his Heavy Metal calculations for tonearm alignment Vibration Isolation Platform Appendix 2 - Further study of the Technics SL- The “sound” of different turntable technologies 1200 tonearm Appendix 3 - Effective mass Appendix 1 - Drift, Wow and Flutter and audibility Appendix 4 - Tonearm resonances and their effect of speed variation on sound quality Appendix 2 - How accurate is mains (power-line) Appendix 5 - Stress, Strain and Young's modulus frequency? Appendix 3 – Physically centring eccentric records Appendix 4 – Villchur’s available torque test Appendix 5 – Induction motors Chapter 4 - The phono-cartridge Electricity and magnetism Chapter 3 - The tonearm From Faraday to funky Moving-magnet and moving-coil cartridges Introduction compared Tonearm tracking Pros and cons How to calculate tonearm geometry Electrical disadvantages of the moving- Tracking Angle magnet cartridge Distortion Output level of moving-magnet Optimisation cartridges Design equations Output level of moving-coil A problem solved cartridges Paradise Lost Tracking Protractors The effects of mistracking Löfgren/Baerwald Tracking theory Stevenson How is tracking normally tested? Löfgren/Baerwald (58mm inner Action and Reaction radius) The Shure tests Checking alignments Displacement (low-frequency) Calculation test Overhang Gauge Velocity (mid-frequency) test Interaction of cartridge-compliance and arm mass Acceleration (high-frequency) test iii Needle-drop Handbook Testing limits What happened to TTR-103? Chapter 6 – Making records What is the collector or archivist to do? The lathe A market study Neumann Conclusion regarding tracking Scully Active (PHLUX) cartridges Lyrec Technical description A closer look Active circuitry Lathe bed Test Results Turntable and motor Applications information Vacuum -chuck Ceramic cartridges Cutter suspension Cutter-head Appendix 1 - Equivalent circuit of the dynamic Constant-velocity system of a phono cartridge Feedback Appendix 2 - Mechanical equivalents Stylus Appendix 3 – Performance of PHLUX active Heated stylus cartridges Swarf removal Appendix 4 – Moving-iron phono cartridges Pitch control Electronics Chapter 5 - The stylus and the groove Amplification Dimensions Cutter preamplifiers Arrival of stereo Cutter-head power amplifiers Tracing Space utilisation Elliptical styli Computer control Shibata and line-contact styli Pitch control Nude shank Depth control Styli for "78" records Signal processing Tiny dimensions: huge forces End-to end Groove deformation under the weight of The manufacturing of gramophone (phonograph) the stylus records Stress, strain, yield and rupture Mastering Fatigue Processing The groove, stylus and distortion Silvering Tracking distortion (lateral) First negative Tracing distortion Electroforming mother Pinch effect Real ears, sharp eyes and steady Stereo and bad news! hands Downward spiral Stampers from mothers Wavelength loss Pressing Vertical tracking distortion Weight and speed From transients to springbacks A long cycle is a better cycle Springback Manufacturing issues Low rider Fractured groove or “stitching” Oceans apart No-fill and apex damage How much is too much? Pimples and dips Stylus Rake Angle (SRA) Blisters Setting tonearm height Pinch-warp …. for correct VTA Dish-warp …. for correct SRA Eccentricity and a well-aimed …. or playing it by ear punch How many records from how many Cartridge Balance & Azimuth stampers from how many mothers? Fozgometer Electroforming quality Processing Appendix 1 - A model for SRA error How long do stampers last? Appendix 2 - How to measure VTA Recycled vinyl & extenders Appendix 3 – VTA/SRA for CD-4 records Extenders Appendix 4 - Equivalence of imbalance and Manufacturing techniques of early records azimuth Wax masters Appendix 5 - The jumbled legacy of CD-4 Processing Pressing iv Frontmatter Direct Metal Mastering (DMM) Summing-up the evidence Father TeD Elliptical syntax Did they squeak? Why not simply reduce the The end of an era tracking force of the elliptical? Buchmann Meyer patterns Why not Shibata? Frequency response The PHLUX-Feather The coming of stereo Secrets from the dead-wax Appendix 1 – Triboelectric charge Lacquer number and cut Appendix 2 – Audibility of 6µm “flats” Mother numbers and stamper codes Appendix 3 - Cross referencing Kelly and Weiler's An example data Collecting our thoughts Appendix 4 – Shure’s SEK-2 Stylus Evaluation Kit Good breeding? White labels Chapter 8 – Electronics for needle-drops What about first pressings? Recorded velocities “Hot” records Shure’s data Matrix numbers of 78 RPM records Replay limitations Acceleration limiting Appendix 1 – Lathe and cutter-head specification Signals from a phono cartridge Appendix 2 – Dynamic range of records Moving-magnet (MM) cartridges Appendix 3 – Pre-echo Line-up Appendix 4 – What are records made of? Moving-coil (MC) cartridges Appendix 5 – New materials Hardware RIAA preamplifiers Equalisation Chapter 7 – Care of records and Gain equipment Lipshitz and Baxandall conquer all Preservation and Storage of Records The last word? Storage Monte Carlo (or Bust) Heat and light Rumble fumble Attitude Moving-coil transformers and preamplifiers Humidity Moving-coil head-amplifier Handling and cleaning Performance Deep clean Power supply Everyday cleaning Moving-coil transformers Detergents Transformer disadvantages Lubrication Transformer advantages Static electricity and vinyl records Neumann’s last pole Miracle surface The RIAA standard Stylus care SE66 recording equaliser Problem 1 – Dust-ball SAB-74B recording equaliser Problem 2 – Gunk LV60 equaliser and cutter-head power Alcohol problem! amplifier “Ultrasonics” Neumann-pole conclusion Polishing Ceramic cartridges Dunkin’ diamonds Connecting up Basotect / Magic Eraser Non-equalising phono preamplifiers Our experience… DIY flat-response phono-preamplifier Dark diamond Modifying an existing phono preamplifier Magic! Building a non-equalising preamplifier Stylus wear and lifetime Groove Sleuth Mk. II preamplifier Wear and flats Gain blocks and (optional) A misconception equalisation The data Transformers Being wary of wear Signal loop (iLOOP) Sins of omission RIAA+ - Monitoring EQ Just a SEK Groove Sleuth power supply and How often to inspect warm-up Time-lapse test Input cooling Record wear Electronic cooling Micro-hardness How to be cool The Scanning Electron Microscope (SEM) v Needle-drop Handbook Chasing other noise sources out of the True peak system Channel Correlation Coëfficient Our implementation Recording-characteristic equalisation in Stereo Moving-coils too Lab Groove Sleuth Adaptors Why it’s better performed in the digital domain Appendix 1 – Mathematics of tolerance REASON 1: A preservation Appendix 2 - Noise in a bipolar junction transistor master with maximum resolution Appendix 3 - Flicker noise REASON 2: Filter accuracy and Appendix 4 - Acceleration limiting of gramophone stability record grooves REASON 3: Better warp and rumble handling Chapter 9 – Digital preservation REASON 4: Flexibility of reformatting equalisation characteristics A digital archive Standard equalisation options available in Converting your record collection to digital Stereo Lab files Causal equalization filters Preservation transfer Quadraphonic decoding in Stereo Lab Operation of your archive Other signal processing in Stereo Lab Instance 1 – artefact Phonograph EQ dialogue Instance 2 – primary reference Phonograph regime and noise- Instance 3 – access master reduction Instance 4 – access copy Hum removal Stereo Lab and the digital archive Hum removal bass-boost What is digital? –