What is a two track recording? Is it the same as stereo or as a mix?
When we hear from two ears we can perceive a space. A two track recording is the end product of a fully mixed song originating from more than two tracks. The two tracks are the left and the right channels of a stereo speaker system or headphones. One speaker is for your left ear, the other speaker is for your right ear. Stereo, two track, two channel audio, left and right mix, mixdown (noun), stereo master all mean the same thing. This is the format that consumers use to listen to music. This is what you will need in order to casually listen to music in your home stereo, car stereo, or portable device like a smartphone through headphones, AirPod, earbuds, etc. Most vinyl records, cassettes, and all CDs, MiniDiscs, MP3s, AACs, and streaming audio is made into a stereo mix. Audio for films (motion picture, movies, etc.) also has a long history with various stereo formats and ways of playing them back.
A side note, some studio recordings in the early 60s used a two track recorder the way an early multitrack recorder would later be used (more on this below). They recorded vocals on track 1 and all of the instruments on track 2 simultaneously. This would allow the engineer to get the right balance between the vocals and the instruments after the recording to make a mono master recording. Technically this is also a two track but these would only be master recording tapes made by the world's top studios and artists between 1957 and 1963.
Then what is a home stereo?
Stereo, meaning the piece of home electronic equipment used to listen to music/audio on records, cassettes or AM/FM radio, is short for "home stereo receiver" which was a term used to contrast it from a mono receiver that came before it. If you think of the larger, wood furniture radios from the 30s, this was a home radio receiver with one speaker (mono). So "home stereo receiver" got shortened to "stereo", to mean the hardware that is a AM/FM radio receiver with amplifier and two speakers, capable of receiving the signal in stereo and hearing it in from speakers, when FM stereo transmissions were a new thing.
Why are song numbers on an album called tracks? Is this the same thing as a recording track?
Sometimes a song is called a track, which originated during the transition of 78RPM records to 33 and 1/3 RPM records in the 1950s. 78s were only long enough for one song per side, and they were mono (one track, one speaker). With 33 and 1/3 records there was room for several songs. Not every individual segment that was separated by silence on a record was a song. You might have narration, different movements of a piece of classical music, etc. So the term "track" came into use. But, unfortunately, there is another definition of the word "track" when talking about recorded audio. When Les Paul (also invented the electric guitar) developed a tape head that could record on just one part of a length of tape, coincidently around the same time as the 78 to 33 1/3 translation, the term "track" was used. It might have been adopted from the analogy with the railroad. In a railyard there might be multiple lengths of tracks running in parallel with train cars on them. When we say tracks in this discussion we are talking about a single instrument recorded on a multitrack tape recorder or hard disk recording system that would be part of a song or audio work, not the number of songs on an album.
What is multitrack?
A multitrack recorder is a tape machine, hard disc recorder or DAW interface that can play and record more than two tracks or any number of tracks (including just one) at the same time. A multitrack recording is a tape or other medium made with a machine that could record with more than two tracks. An instrumentalist might play all of the instruments on a songs by recording one track at a time, playing back recording and listening and playing along with them while recording a new one as Tom Scholz did with the first Boston album. This process of listening to recorded tacks as playback while recording on other tracks at the same time is known as overdubbing. It is also possible to switch between playing and recording on a same track on the fly, often used fix a mistake, known as a punch-in. Or, multiple takes of a part could be recorded on multiple tracks and then mixed to another track, know as a comp or comping. Another way to use multitrack recording is to have an entire band record on multiple tracks simultaneously, where each microphone records to one or more tracks. The first two Beatles albums, in 1963, "Please Please Me" and "With The Beatles" were recorded without a multitrack tape machine. It was direct to two track. "I Want to Hold Your Hand" (also in '63) was the first Beatles song recorded on a 4 track. This meant that George Martin could record it without the pressure of capturing the band's performance with a perfect two track mix, which he could mix later when the band went home. The tape could be played back multiple times, with an unlimited number of chances to get the mix right. "Hey Jude" recorded in 1968 was the first Beatles song to use an 8 track tape machine.
What is tracking and mixing?
The act of recording tracks in a multi track setup is called tracking. It is possible to record all tracks at once or just some tracks. The act of taking a multitrack tape recording and transferring it into a stereo or 2 track recording while going through mixer is called mixing or mixing down (down from many to few) and the end recording is sometimes called a mixdown or stereo mix. In the days before digital audio workstations (DAWs) a multitrack tape (a 4, 8, 16, 24 track tape system) would be played by a multitrack tape machine (which could both play and record) into a mixer. An engineer listens to the mix through speakers and makes adjustments to the level, EQ, panning, effects and dynamics of each and every track, positioning them so they can all be heard. The engineer strives to make a stereo mix sound full and wide by doing things like panning the tracks from two mics all the way to the left for one and all the way to the right for the other. Panning is controlling how much of a track comes out of one of the two speakers, similar to the knob on a home or car stereo called Balance. An example of this might be two mics used to record a single instrument like an acoustic guitar. This is how to make good use of the what is called the stereo field. Early uses of stereo recordings by The Beatles might place drums and guitar on one side and bass and vocals on the other side. The output of the mixer is connected to a two channel tape recorder. In a modern DAWs setup the mix is done on on a virtual mixer on a computer screen, automation and digital effects are added, and the mix is rendered into a stereo/two track .wav file. Most important instruments in today's mixes tend to be panned in the center so that the listener does not feel off balance by too much material in one ear, which one might experience in some early Beatles songs. The thinking was that the listener wanted to feel like they were in the middle of room where the performance was happening.
What is mastering?
In the early days of music production, after multiple songs are mixed to two track, the tapes would then get cut up (literally cutting with razor blade) and then splice back together in the right order to assemble the individual songs. This is called sequencing. A mastering engineer would then will take all of the songs and adjust the level, EQ, and dynamics again to make them sound like they all go on the same record. The master then gets delivered to the vinyl pressing plant, CD, manufacturing plant, cassette duplication plant, or a stereo .wav or .aif file gets uploaded to a streaming service where it may get converted into yet another format that optimizes it for streaming for listeners or for downloads. This part of the process is optional but necessary if you want your song to "sound as loud" as other mastered songs out there. This is why you may want to get your album mastered, and mastered for particular mediums. Mastering for CD, vinyl, streaming are all done slightly differently.
What is a "master recording"
When a particular tape is called a "master recording" that means there are no other copies that are fewer generations than it. It is the tape that was originally used to track to or that was mixed down to.What is mono?
A mono recording is a 1 track recording. With a mono recording the same thing will come from both speakers if there are two speakers. Early vinyl pressings were only available in mono until it was discovered how to to make them in stereo. Mono recordings may tend to sound more flat but also more detailed, but it is a matter of taste.
Who does the mixing?
When we transfer your multitrack tape you should have a professional mix engineer in mind to deliver the tracks to for mixing. Or you might mix it yourself in any DAW. However, mixing is no easy task. It is a very competitive field with many trade organizations, magazines, technical publications, Grammy Award categories and university major programs dedicated to the art of mixing. There are highly-sought after engineers that are famous for their mixes that can charge the highest fees in the industry. Some might specialize in specific genres of music, some might do mixes for a variety of styles. If you do not have a mix engineer in mind you might consult Deep Signal Studios for their mixing services.