The numbers 33, 45 and 78, used in relation to vinyl records, refer to how much they cost in different decades

The numbers 33, 45 and 78, used in relation to vinyl records, refer to how much they cost in different decades

The numbers 33, 45, and 78 actually refer to the rotational speeds (in revolutions per minute, or RPM) at which vinyl records are played.

• A 33 RPM record is known as a "33⅓" or "LP" (Long Play) record, and is the most common speed for full-length albums.
• A 45 RPM record is typically a single with one song on each side.
• A 78 RPM record is an older format that was used for early shellac records, primarily in the early to mid-20th century.

These numbers indicate how fast the record should spin on a turntable in order to reproduce the recorded sound at the correct pitch and duration.

What is RPM?

RPM, or Revolutions Per Minute, is a measure of how many full rotations an object makes in one minute around a fixed axis. In the context of vinyl records, RPM is used to specify the speed at which the record should be played on a turntable. This speed is crucial for accurately reproducing the recorded sound.

A standard vinyl record typically plays at one of three speeds: 33⅓ RPM, 45 RPM, or 78 RPM. A 33⅓ RPM record, often referred to as an LP (Long Play) record, is the most common speed for full-length albums. These records are played at a slower speed, which allows for longer playing times per side.

A 45 RPM record, on the other hand, is typically a single with one song on each side. These records are played at a faster speed, which allows for higher fidelity but shorter playing times. Finally, a 78 RPM record is an older format primarily used for early shellac records. These records are played at the fastest speed and are less common today.