At the beginning, separate disc recordings were synched up to film recordings with difficulty, before adaptors were invented that could link the process more easily. Stereo sound and magnetic strip technology started to rise in the 1930s, providing filmmakers with greater editing powers.

Optical sound was overtaken by magnetic strip technology in the 1930s but both remained in use for many years, as well as the continued use of silent film. With silent films, magnetic sound films and optical sound films all being produced simultaneously.

Each new technology became more affordable as decades passed and companies started producing consumer-based recording equipment and so many people have been able to make sound films of their own at home. But competing technologies and overlapping usage lead to some serious confusion – it’s really hard to know if you’re looking at a sound film or a silent film!

Many families may have the problem of trying to figure out if the box of 16mm, Super 8 and Regular 8 cine films in the attic have sound or not. But we’ve got quick and easy tips for figuring out if your films have sound:

There are 2 types of sound recording technology that were used back in the days of cine film: magnetic stripe and optical sound. Both leave distinctive visual marks on films and provide quick ways of identifying if a film could have sound and may indicate if it’s mono or stereo.

It is worth bearing in mind that these rules are no guarantee of conclusively knowing if a film has sound and are better considered as indicators whether a film was capable of storing sound at the time of production. There is no way of knowing for sure if there is sound present on a film without playing it through a projector with sound capability.

Magnetic Sound Stripe:

1. Yellow or rust-coloured borders down one or both sides of the film.
2. In the case of 16mm film which normally have sprockets down both sides (chain of regular rectangular holes), 16mm film with sound will only have sprockets down one side.
   

Optical Sound Line:

1. A black border down one side with 1 or more thin clear wavy lines (these are soundwaves).
2. 16mm cine film with sound will have sprockets down one side only (silent 16mm film will have sprockets down both sides).
   

Checking for Stereo Sound on Film:

1. Optical sound lines with more than one thing wavy line usually indicates stereo sound.
2. Magnetic sound films with yellow/rusty borders down both sides may indicate stereo or 2-channel sound, but is not a guarantee. In the case of Super 8s which were often made with 2 magnetic stripe borders as a way of balancing the film so it ran smoothly through the gate of the camera, the second stripe would normally be left blank. But you never know! You might get lucky.

We’ve got a guide to help you figure out if your cine film reels have sound:

• Super 8
• 8mm
• 16mm

• Super 8 films, of all consumer bought cine films, are the most likely to have sound included, compared with regular 8mm or 16mm film.
• Super 8 films started being released with sound technology in 1973, so if your film is dated before then it is unlikely to have sound.
• As with our quick tips from earlier, look for the magnetic yellow strips down the sides of the film or for the optical soundtrack that appears as a black border with visible soundwaves down one side of the film.
• Super 8 films with magnetic sound were usually made with the magnetic stripes (yellow/rusty borders) down both sides to give the film balance and allow it to run smoothly through the camera’s gate.
• Having 2 magnetic stripes made it possible to record more than one audio channel on Super 8 film.
  • Mono sound was more common than stereo. The camera would normally record one channel of audio onto the main (wider) stripe only.
  • But 2 channel sound or stereo sound was possible. Some projectors were capable of recording sound onto the balance (thinner) stripe as well, perhaps to add music or narration to accompany the main soundtrack. This became popular with later releases of Hollywood films.

• Regular 8mm sound films do exist but are far less common than Super 8s. However, they are common enough to be standard in our digitisation lab.
• Look for a single border of yellow down the side next to the sprockets as an indicator for having sound. This single border of yellow is an indicator of a magnetic strip of mono sound. 8mm films were not produced with stereo sound.
• 8mm films are largely unknown to be made with optical sound, so the yellow strip is the most reliable indicator of sound being present.

• 16mm films can have sound but of the 3 common cine film sizes, 16mm films with sound are the rarest but we still come across them in our lab.
• 16mm cine films were produced both with optical soundtracks and magnetic strips.
• For 16mm magnetic sound film look for the yellow strips down one side (for mono audio) or both sides (possible stereo audio).
• For 16mm optical sound film look for a thick black border down one side with thin wavy lines running the full length. 1 line indicates mono and 2 or more indicates stereo.