Multi-Track Recording and Mixing (Part I)

In Uncategorizedby tfwm

Years ago, multi-track recording was a specialized function limited to the large commercial recording studios mostly found in major metropolitan areas. State-of-the-art facilities provided large-format multi-track tape machines, mixing consoles, racks of outboard processing equipment (remember the plate reverb) and a wide variety of microphones. But in the last 10 to 15 years, things have changed. No longer is there a need to rent a studio and pay a bunch of musicians to record a song. Multi-track recording is no longer the sole domain of the large recording studio. It has moved into the bedrooms, basements, and storage rooms of musicians and songwriters. Small studios capable of producing outstanding quality recordings have become affordable and more commonplace in all areas of the music industry.

The changes have largely been the result of emerging technologies. Small, affordable mixing consoles, computer-based digital audio workstations, sequencers, synthesizers, samplers, digital tape, hard disk recorders and CD writers have revolutionized the way many of the songs we hear today are being recorded, produced and distributed. Where it used to take many hours of studio time, several musicians and a technical crew to get a song recorded, it can now easily be done in a small area with a bit of relatively affordable equipment, and in a rather short period of time.

Naturally, this trend has found its way into Christian music. Today, most every church with a substantial music program has recorded and distributed music, or has at least thought about it. Some have extensive libraries of recording projects that are sold all over the world. Many average to large size churches that are building – or looking to build – a new facility are installing or planning for a dedicated multi-track recording facility. Using readily available recording technology to communicate the message of a ministry is a no-brainer.

There are generally two uses for multi-track recording: audio recording and post-production for video, and multi-track recording for music production. While it makes sense for many churches to delve into the realm of multi-track recording, it should be done with careful planning and a clear goal in mind. The first task is to determine what the finished product will be and why you are going to produce it. Otherwise, both time and money are wasted in trying to figure out what best to do and how best to do it.

Audio for Video

Many churches are video recording worship services for purposes ranging from worship team training and evaluation, to distribution for shut-ins, to TV broadcast. Not only are worship services recorded, but special holiday productions, musical concerts, or other special events are often worthy of video recording and distribution. While most of the larger churches with a TV ministry have been doing a professional job of both the audio and video production for many years; there are many ministries that are new to the realm of video production and the associated requirement for acceptable audio in support of the video.

When considering a video ministry of any type, careful consideration should be given to the associated audio requirements. An audio feed from the main sound system mixer generally does a poor job of providing good sound for video. For example, while a set of acoustic drums provides a good deal of acoustic energy to the listener in the room and may need little reinforcement from the sound system, the audio mix off the house console will lack a good balance to a listener watching the video. Since the viewer is not in the room to experience all the natural acoustic events, audio must be recorded and mixed separately for the video. Consideration must be given to additional microphones that might otherwise not be necessary for live sound – including microphones for acoustic or non-reinforced instruments and ambient room microphones that will give the viewer a sense of being in the room during the performance.

If video recording is to be done with little or no budget for audio equipment, one (very difficult) technique for providing audio is to route a separate mix off the sound system mixing console as mixed on an auxiliary bus. In order to make sure the mix is adequate for video, however, the mix must be monitored on headphones and will surely keep the mix engineer’s hands full as he (or she) has to mix the main house system, monitor speakers, and a video mix all at the same time. If the audio quality for video is important then a separate audio control room and audio mix is required.

The audio-for-video mix usually begins by splitting the main sound system microphones at a split location somewhere between the microphones themselves and the main sound system mix console. Ideally this split is accomplished through active microphone splitting circuitry or through a passive transformer isolation split. A separate control room that is not connected to the main worship center is needed to accurately monitor what is being recorded onto tape. In addition to good sound separation from the worship center, this control room should be designed by an experienced studio designer with good acoustics in mind, and should be fitted with accurate monitor speakers.

In a multi-track audio for video control room, tape machines or hard disk recording equipment is synchronized to the recorded video through the use of SMPTE (Society of Motion Picture and Television Engineers) time code. The society has devised a standard by which video or film and audio can be easily and accurately synchronized with one another throughout the entire process of recording, editing and mixing.
Multiple channels of discrete audio are recorded onto discrete audio tracks for future mixing and dubbing over to video. For example, vocalists, keyboards, guitars, bass and other individual instruments can be recorded onto their own audio tracks. Instruments such as drums can have as many as 10 (or more) tracks associated with the individual pieces within the set. If each instrument is recorded onto its own track, isolation, separation and control over the final mix can be better achieved.

After the event is recorded, additional instruments can be added or re-recorded in the post-production phase. Individual tracks can be recorded one at a time or in groups as needed to improve the quality. After all recording is complete, the individual tracks are mixed together to provide a good audio representation of the activity that is recorded on the video. The finished mix is then dubbed onto the edited videotape to produce the final product.

Recording for Music Production

While many music recordings are made in conjunction with video recording, there is often a requirement to record solely for the purpose of creating a music CD. Recording a live worship CD would be very similar to procedures described above in audio recording for video. Individual instruments would be recorded onto individual tracks for later mixing. But creating a music CD studio project can be quite a different story.
Both a live video project and a dedicated CD project take a great deal of pre-production time and effort. But the actual recording time involved in creating a studio project is generally much greater. Song writing, song selection, musical arrangements, rehearsals, if done prior to recording sessions, can make the studio time much more efficient and effective. Even though the process may be longer and more tedious than a live recording, the end result is usually more polished with better audio and musical quality.

Once recording begins, there are generally three phases in the process. The first session is usually known as a “tracking” session where the basic song tracks are recorded. These usually include the rhythm instruments such as drums, bass, keyboards and guitar. Often times a “scratch” vocal track will be recorded along with the basic tracks in order for musicians to follow where they are in the song. This scratch vocal is used as a guide and is usually erased when the vocals are recorded later.

Depending on the type of music being recorded, the tracking session may be nothing more than synchronizing a sequencer, samplers, keyboards, or other electronic sources to the recording media to transfer individual sounds to individual tracks. Or it may require a full complement of strings, woodwinds, brass, percussion and other instruments to provide the basic tracks.

The second phase may include multiple sessions where additional instruments and vocals are added to separate tracks while listening to a rough mix of the basic tracks. This is known as overdubbing. Multiple takes can be created to allow for selection of the best performance, or for using various portions of each performance in order to create a composite recording. Another overdubbing technique is to record multiple tracks in several passes of a certain part to “layer” or “double” the sound.

The final phase of the recording process is the mix session where all tracks are combined to create the final product. All the recorded tracks should be clean, free of distortion and recorded well enough to produce a good final mix.

The final mix session is also where outboard effects processing are generally utilized. Adding reverberation or delay to the dry recorded tracks can help provide a more live or natural sound. Dynamics processing such as compression, gating, or expanding can help to smooth out an otherwise uneven vocal. A harmonizer can be used to provide a fuller or richer sound. Equalization can be used to make for a more pleasing frequency response for various instruments.

Mastering of the final mix is another step that can help to provide an improved product before sending to CD duplication. In the mastering process, overall equalization is set, levels are matched from one song to the next, and any other fine-tuning is done prior to duplication. With some lower budget projects, this step is often omitted. If the overall recording is very consistent from one song to the next, the project stands a good chance of sounding ok without mastering. Otherwise, it’s best to send the final mixed project to a good mastering engineer for final preparation. If the product is being done for a record label for distribution, they will most certainly want to include mastering in the project.

Other Uses of Multi-Track Recording

Today, with the extensive digital audio recording, editing and sound production techniques available at relatively low costs, many song writers and musicians have turned directly to multi-track recording in one form or another as a way of creating the final product as they go. This might include song writing, arranging, and recording all at the same time, making changes as they go. Others are making use of playback of multi-track recorded media in support of a live sound application. These can include playback of pre-recorded background vocals, instruments, or whatever is needed to make the performance more complete. But whatever the use, the equipment and techniques that are available today have made multi-track recording a powerful and accessible tool.

Part two of this article will address techniques, recording formats, equipment and facilities necessary to effectively provide multi-track recording support for ministry.