Voice Over and ADR

ADR, also commonly referred to as ‘dubbing’, is a pivotal part of our Sydney Recording studio, Crash Symphony Productions. In this article, we are going to look specifically at ADR. We will look at what ADR is in the film and TV industry; why ADR is often necessary in screen work; and how we record ADR here at Crash Symphony Productions.
ADR is the acronym for Additional Dialogue Replacement, but is also sometimes referred to as Automated Dialogue Replacement, or dubbing. It is a technical phase in the post-production process of filming, where audio is recorded after the original camera recording. ADR is most commonly recorded when the actors need to replace their dialogue. ADR work is almost always recorded off the film set, in a high-end recording studio.
The difference between ADR and voice over, is that voice over is recorded without the intention of synching it with the screen after. However, it can be used as a narration or soliloquy in film. ADR is specifically recorded with the intention of having the actor synching their voice with what is being said onscreen.
There are a number of reasons why ADR might need to be recorded. The most common is that the audio equipment and/or the sound of the set was too noisy or ambient to capture a good, clean vocal sound for the actors.
Alternatively, perhaps a foreign language is being synchronised over the top of what the actors appear to be saying, so that the film can be released in multiple languages. Otherwise, the film may require a soliloquy (narrator’s voice) to be tracked over the top of sections of the film. It may also be that the actor/s were unable to perform their lines in the way the director had hoped, and a second performance in the studio is required in order to capture this, before the film can be completed.
Often, the ADR recording session relies heavily on how well the actor can synchronise their voice in the studio to what they appear to be saying onscreen. For this reason alone, the actors will require a clear picture- it is ideal to have a large screen available, or have the lips highlighted and magnified, to increase the actor’s ability to see their onscreen performance. The actors will be positioned in a quiet isolation booth directly in front of the screen, where they can focus on synching up their vocal performance.
In an ADR session, audio engineers will often use two kinds of microphones: A lapel microphone placed close to the actor’s lips, and a high-quality studio voice over microphone.  The lapel microphone will equate to the sound of the microphone that was most probably used on set, whereas the studio microphone will be the signal that is substantially higher in quality than the sound of the on-set signal.
If the director is looking to replace the vocal that was capture on the day of filming with a similar on-set sound then they will use what was recorded through the lapel. If they want a complete replacement with a signal that is extremely high in quality, then they will most likely choose the studio voice over microphone. Sometimes, a blend of the two different signals may be the appropriate choice.
Here at Crash Symphony Productions, we use a DPA lapel microphone. This microphone is positioned on a microphone stand with a long flexible arm that allows for surgical positioning of the microphone, in close proximity to the vocal source, but without the rustling sound that can be quite prevalent when the Lavelle microphone is clipped to the actor’s clothing. The high-end studio microphone is either a shotgun microphone like the Seinheisser MK416, a large diaphragm condenser microphone like the U47, or an AKG 414.
The Seinheisser 416 is the most popular microphone for ADR work, because it is a highly directional and focused microphone that can be positioned far away from the actor and still capture a great audio vocal signal. It does, however, lack the depth and bottom resonance of the U47. Nonetheless, it does have a characteristic signal that is favoured by film directors all over the world; and for any serious ADR studios, this microphone is a must-have.
If the director wants a microphone sound that is ‘larger than life’, and perfect for the soliloquy (or narrator-style) ADR recording, then a large diaphragm condenser is the microphone of choice. We use the U47 large diaphragm condenser tube microphone for these types of ‘larger-than-life’ recordings.

TV and Film are recorded at a sample rate of 48kHz

It is important for audio engineers to remember that ADR, and most voice over sessions, should always be recorded at a sample rate of 48kHz. This is because it is the standard that is used in the TV and film industry. The only other sample rate used in ADR would be 96kHz, which is used in high definition TV and film.
The technical explanation for deviating from the common music recording sample rate of 44.1kHz to 48kHz really warrants another article. In short, that standard of 48kHz has its foundations in its relationship to video frame rates, and the politics of agreeing on an audio standard, back in the early 1980’s when digital audio was still in its early days and just finding its place in the world.

3 bells, or pings, are often integrated into the mix so that the actor can hear when their line is approaching

It is almost always the case that in an ADR session, there are three beeps integrated into the DAW that are designed to cue the actor. The three beeps are placed in the lead-up to the entry of the line that they are trying to synchronise dialogue against. Once the actor becomes familiar with where the three beeps are located (relative to the entry point), it will help them come in at the right location in subsequent takes of ADR.
Some engineers will create the beeps by using a sine wave generator and placing the beeps not only equidistant from each other, but also the same distant from the last beep to the beginning of the ADR line. This use of rhythm aids the actor in where they need to enter with their dialogue.
Without this use of audio cueing it is very difficult for the actor to enter at the right location and the session can really become driven by the luck of the actor entering at the right time. Creating clear and rhythmic beep cues is critical to running a successful ADR session.

SMTPE time code and its relation to ADR

SMPTE time code is a big part of working on TV or film projects. This is a code that helps the video and audio projects stay in synch. When dealing with SMPTE time code in the audio arena, it appears as a number in the transport bar that allows the audio engineer to accurately position the audio where the director and production team need to have the audio. It also creates a highly accurate reference to locations in the video, so the video team might say that they need the audio to start at “SMPTE time code position XXXX”. They might add that they want the audio to stop recording at “SMPTE time code position YYYYY”. Using SMPTE time code allows people working on the film to use the same language when referring to positions in the production.

Creating the ideal conditions for the actor to track ADR and voice over

Creating the ideal conditions for the talent to work in, is a huge part of running a successful ADR and/or voice over session. The following are some of the things that we, at Crash Symphony Productions, like to have in place for this kind of session.
It is important to have a recording space that maintains room temperature. By room temperature we are referring to the scientific standard of 25 degrees Celsius. The ability to deviate from this as asked by the actor or voice over artist is also really important. It is critical that the room temperature does not change during the recording session. The recording space also needs to be well ventilated with a constant supply of fresh air. The air must not be dry or overly humid. Dry air means that the actor’s vocals could dry out prematurely and when the air is too humid it can result in some discomfort to the actor. One of the biggest costs to setting up a recording studio is having a recording booth or space that caters to these conditions.
Also, for actors that need to be recording ADR, it is really important to have a screen setup that is quite large. A large screen will allow the actor to easily focus in on the lips as they synch dialogue to their performance on the screen. Small screens will not allow for this kind of work to be successful.
Our most recent ADR work was with 20th Century Fox, for the television show “24: Live Another Day”.