Vinyl records were once the best way to listen to music, and many music enthusiasts still believe that records provide a better, more pure sound than other recording and listening technologies, especially for music that was specifically recorded to be played on records.
Records are produced in a few different sizes, each with a different purpose and different dimensions.
How do records work?
When a song is recorded onto a record, the vinyl is imprinted with a very specific pattern of grooves in a ring around the record.
As the record spins, the record player’s needle moves over the pattern, creating vibrations.
These vibrations are converted to electrical signals, which produce the sounds of the song.
Originally, the very first records were made of beeswax, and they were cylindrical in shape.
Beeswax was easy to imprint, but it wasn’t durable, and heating it could damage the imprints.
Later, record makers switched to vinyl. Vinyl was used to make records because it’s relatively durable and also very smooth.
This helps to eliminate friction and makes it easy for the needle to glide across the surface.
What are different record sizes used for?
Records are sized differently because different records are designed to hold more or less music playtime.
For example, a 78 record will usually hold between three and seven minutes of music on each side.
A larger 33 record has a playtime between 12 and 22 minutes of music on each side.
Forty-five records, which are even smaller than a 78, usually have a playtime between nine and 15 minutes per side.
These records are also designed to be played at specific speeds.
The numbers 78, 45, and 33 all refer to revolutions per minute, or RPM.
The higher the RPM, the shorter the playtime will be.
A record can be played at a different speed, but playing it at a speed it wasn’t created for will distort the sounds.
Thirty-three records almost always have a larger physical size than a 45 or a 78, but the suggested RPM and the physical size of the record don’t always correlate.
Dimensions of a 33 Record
A 33 record actually has an RPM of 33 1/3, but the name was shortened to 33 for simplicity. This type of record is generally called an LP, or long-playing, record. Although the 33 RPM speed can be used with other vinyl record sizes, 33 records are almost always 12 inches, or 30 centimeters, in diameter.
If a 12-inch record was designed to be an EP, or extended play, record, which is a record that holds less than a full album’s worth of music but more than a single, the 12-inch record will most likely need to be played at 45 RPM.
Each 33 record is between .02 and .03 inches or .6 and .7 millimeters thick. Exactly how thick the record is will depend on the manufacturer and how the record was made.
A record cover, also known as an album sleeve, is only slightly larger than the record it holds.
A cover for a 12-inch or 33 RPM record is 12.375 inches wide and 12.375 inches tall.
The covers are about half an inch thick.
Most record covers are made of lightweight cardboard or paper. They often have a much thinner inner paper sleeve to help protect the record.
Many record covers, particularly the inner sleeve parts, have a round cutout in the middle so that the paper label of the record can be seen.
Dimensions of a 45 Record
Although 45 records can sometimes be as large as 12 inches in diameter, almost all 45 records are 7 inches or 17.5 centimeters in diameter. Like other records, 45 records are between .02 and .03 inches or .6 and .7 millimeters thick.
These records are usually used for recording singles, and they usually only hold one song on each side.
This is where the term B-side came from.
The single song, which was part of the album, would be pressed into the A-side of the record.
Another song, which usually wasn’t on the full-length album, was on the reverse, or B-side, of the record.
The album sleeve for a 45 record is usually 7 and 5/8 inches square, with a thickness of about half an inch.
Dimensions of a 78 Record
The 78 record was designed to hold EP albums or singles with more than one B-side. These albums are usually 10 inches or 25.2 centimeters in diameter, with the same thickness of .02 to .03 inches.
These particular records tend to be a bit less common than 33 or 45 records.
The 78 record decreased in popularity with the rise of the 45, which was smaller and therefore easier to store and less expensive to produce.
Most record players were also designed to be switched between 33 and 45 RPM, so playing a 78 record could sometimes be a bit challenging.
Although most 78 records are 10 inches in size, some 12-inch records were designed to be played at 78 RPM.
The cover for a 78 record is almost always 10 and 3/16 inches by 10 and 1/8 inches in size.