Difference between revisions of "Myths (Vinyl)"

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m (Vinyl Myths moved to Myths (Vinyl): Making vinyl-related topics be a consistent format.)
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Revision as of 17:01, 8 September 2006

Note: These are preliminary notes, are a little opinionated, and are subject to change. Please edit as appropriate or comment on the discussion page.

  • The vinyl surface is heated to several hundred degrees on playback, and repeat play of the same track should wait at least several hours until the vinyl has cooled.
    • Professional estimates for the stylus surface temperature during playback are 300-500 F.
    • Obviously, the temperature of the record is at or close to room temperature except at the stylus contact point - otherwise the record would completely melt.
    • It is true that back-to-back playback will introduce slightly more distortion than a fresh play. This is believed to be a temporary effect and goes away after approx. 10 minutes.
    • Repeated playback (no matter what the timeframe) carries the risk of permanent damage. Obviously, records are observed to wear out with repeated play.
    • No published evidence exists of back-to-back playback causing any more permanent damage than if repeated plays are separated by any longer period of time.
  • Proper vinyl playback is click-free.
    • Pops and clicks are often not audible during a song on a well-maintained record and should not distract from the listening experience.
    • No evidence exists of a record that is shown to be played back with absolutely no pops or clicks whatsoever.
    • They are introduced at virtually every stage of production, from cutting the laquer to the pressing to the playback itself. Some pops and ticks are pressed into the record itself.
    • Some pops and ticks result from static discharges during playback. However, this may be mitigated by the use of topical treatments on the record.
    • Because of the lack of evidence for a tick-free record and the engineering factors making such a record extremely rare, it is quite likely that no record exists that is truly free from all pops and ticks.
  • Vinyl is better than digital because the analog signal on the vinyl tracks the analog signal exactly, while digital is quantized into steps.
    • PCM encoding (used on CDs and DVD-A) records audio data in a quantized format. Analog formats do not have a measurable time or signal resolution.
    • Analog encoding still has many measurable and audible faults, potentially including THD, noise, IMD, etc. These distortions have invariably measured higher than for digital formats, including CD.
    • PCM can encode time delays to any arbitrarily small length. Time delays of 1us or less - a tiny fraction of the sample rate - are easily achievable. The theoretical minimum delay is 1ns or less. (Proof here.)
    • Signal quantization (ie 16-bit or 24-bit) only results in increased noise in a correct implementation. No distortion is introduced and the noise is of questionable audibility under most listening conditions.
    • The term "analog", by definition, means that the signal is not and cannot be a perfect reproduction of the original - it is merely an "analogue" of the existing signal, corrupted in the process of encoding.
    • In short, by any numerical basis, vinyl is not as accurate as competing digital formats.
  • Vinyl has greater resolution than CD because its dynamic range is higher than for CD at the most audible frequencies.
    • The dynamic range of vinyl, when evaluated as a the ratio of a peak sinusoudal amplitude to the peak noise density at that sine wave frequency, is somewhere around 80db. Under theoretically ideal conditions, this could perhaps improve to 120db.
    • The dynamic range of CDs, when evaluated on a frequency-dependent basis and performed with proper dithering and oversampling, is somewhere around 150db.
    • Under no legitimate circumstances will the dynamic range vinyl ever exceed the dynamic range of CD, under any frequency, given the wide performance gap and the physical limitations of vinyl playback.
    • Thread here.
  • Adding a penny to the headshell improves tracking/sound.
    • The trackability of a cartridge is related to the mechanical parameters of the tonearm and stylus assembly.
    • Adding weight to the headshell (and adjusting the counterweight to compensate) increases the effective mass of the tonearm and reduces its resonant frequency. If the resonant frequency is excessively high - 15-20hz as measured by a test record - the weight may improve trackability by moving the resonance out of the audible range. Otherwise, it will generally only reduce trackability.
  • A cartridge is permanently damaged and should be replaced if the stylus appears even slightly bent.
    • Bent stylii cause azimuth and alignment errors which may be audible. In extreme cases they can cause record damage.
    • Cartridges are hand-built and always have some finite tolerance in their construction. No stylus is perfectly straight.
  • Belt-driven turntables are better than direct-drive turntables.
    • Belt drives are far easier to implement than direct drives, easier to improve, and arguably easier to repair.
    • Well built direct drives have speed and rumble tolerances as good or better than well built belt drives.
    • Subjective claims to the improved musicality and audio quality of belt drives are disputed and not well agreed upon by all listeners.
    • Belt drives hold their value just as poorly in the used market as direct drives.
    • Direct drive motors tend to last a very long time (some original-model SL1200s may still run without any maintenance). Belt drives need new belts on a semi-regular basis and tend to have noisier motors at the same price ranges as direct drives.
    • There is a common myth that a direct drive will "hunt" for the correct speed and cause audible speed variations. This has no basis in reality.
    • It is believed that direct drives are better at handling dynamic stylus friction than belt drives, except in cases of very poor direct drives or very good belt drives.
    • Some examples do exist of direct drives of inferior quality.
    • Stock tonearms on direct drives tend to be much less expensive than the tonearms that come with belt drives at similar price points.