Any flat disc record, made between about 1898 and the late 1950s and playing at a speed around 78 revolutions per minute is called a "78" by collectors. Generally 78s are made of a brittle material which uses a shellac resin (thus their other name is shellac records).
Although the speeds of the earliest discs can vary considerably from 78 rpm they are still called "78s". The recording speed chosen was a compromise between playing time (faster = shorter playing time), groove and needle size, wear on the record and needle, and fidelity of reproduction. At first the speeds were not standardised but ranged between 65 and over 100 rpm, but in the 1900s an average speed was around 78rpm. The first disc recording machines were weight driven with the speed controlled by a governor and different calibrations between machines could lead to speed differences. When electrical recording was first used in 1925, it was used for the soundtrack of films and so a precise speed was needed to keep in sync with the picture. In America using 60Hz mains, the speed of electric motors is either 3600 or 1800 rpm. Using a 3600 rpm motor with a 46 : 1 reduction gives a speed of 78.26. A similar calculation for England using 50 Hz mains gives a speed of 77.92 rpm. These speeds became the standard for the rest of the 78 rpm era. The LP speed of 33.33 rpm and the vinyl single speed of 45rpm comes from a similar calculation of speed reduction from a syncronous motor.
Whilst a 78 made from shellac is brittle and relatively easily broken, both the LP (Long Playing) record and the 45 rpm single are made from vinyl plastic which is flexible and unbreakable in normal use. 78s come in a variety of sizes, the most common being 10 inch (25cm) and 12 inch (30cm) diameter, and these were originally sold in either paper or card covers, generally with a circular cutout allowing the record label to be seen. LPs usually come in a paper sleeve within a colour printed card jacket which also provides a track listing. 45 rpm singles and EPs (Extended Play) are of 7 inch (17.5cm) diameter, the earlier copies being sold in paper covers. If you compare a 78 with either an LP or a single, you will find that the grooves on the 78 are much coarser. Thus collectors of 78s call the LP and 45 single either a "microgoove" or vinyl record.
You have two options - a wind-up gramophone or a hi-fi system.
For an authentic vintage sound, most collectors have at least one wind-up gramophone. In looking for a gramophone, be aware that there are a large number of fake "horn" gramophones. These originate in India, and are made from parts of old machines, fitted in a new case and usually with a brass flower horn. The most reliable gramophones are those made by the well known companies such as HMV and Columbia. Wind-up gramophones use Gramophone Needles, which should be replaced after each record has been played.
If you want to play 78s on modern hi-fi equipment, then you need a turntable with the 78rpm speed and a cartridge fitted with a 78 stylus. These can be obtained on the secondhand market - the Goldring GL75 was a popular turntable in the 1970s and provides a good range of speeds around 78 rpm. Alternatively, Rega make a new 78 rpm turntable with an appropriate arm and cartridge.
For best results on modern equipment, a special phono preamplifier is required to correctly equalise the different types of records. To start with, you can get a reasonable sound by using the normal phono input and adjusting the amplifier's tone controls to suit your taste.
Most collectors start by finding or being given a pile of 78s and, having become familiar with a few artists, trying to find some more of the same. Record collecting now goes back 100 years, and on 78s you can find all sorts of music from every genre. Collectors often concentrate on one of the following types of record: opera, music hall, ballad singers, instrumentalists, jazz, dance bands, swing bands, musical comedy, comedians, film stars, famous politicians, rock'n'roll, #1 hits. As several million titles were issued over the lifetime of 78s, you will never run out of choice.
Before 1925, all 78s were recorded by means of the artist singing or speaking into a horn, the power of their voice directly vibrating the recording stylus and thus cutting the wax of the master disc. Collectors call these discs "acoustic" recordings
After about 1925, 78s were recorded by the artist singing or speaking into a microphone and amplifier which then cut the master record. This allowed a wider range of sound to be recorded. Records recorded by this process are called "electrical" recordings. Collectors can identify these discs by either by listening or by means of small marks in the record surface close to the label.