Reel-to-reel audio tape recording

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Image:Reel-to-reel recorder tc-630.jpg Reel-to-reel or open reel tape recording refers to the form of magnetic tape audio recording in which the recording medium is held on a reel, rather than being securely contained within a cassette. In use, the supply reel or feed reel containing the tape is mounted on a spindle; the end of the tape is manually pulled out of the reel, threaded through mechanical guides and a tape head assembly, and attached by friction to the hub of a second, initially empty takeup reel. The arrangement is similar to that used for motion picture film.

The reel-to-reel format was used in the very earliest tape recorders, including the pioneering German Magnetophons of the 1930s. Originally, this format had no name, since all forms of magnetic tape recorders used it. The name arose only with the need to distinguish it from the several kinds of tape cartridges or cassettes which were introduced in the early 1960s. Thus, the term "reel-to-reel" is an example of a retronym.

Inexpensive reel-to-reel tape recorders were widely used for voice recording in the home and in schools before the advent of the Philips "compact cassette" in 1963. Cassettes quickly displaced reel-to-reel recorders for consumer use. However, the narrow tracks and slow recording speeds used in cassettes compromised fidelity. Reel-to-reel was the main recording format used by audiophiles and professionals until the late 1980s, when digital audio recording techniques began to allow the use of other types of media (such as DAT cassettes and hard disks). Even today, many artists of all genres swear by the analog tape's "musical", "natural" and especially "warm" sound. Due to harmonic distortion, bass can thicken up, creating the illusion of a fuller sounding mix. In addition, high end can be slightly compressed, which is more natural to the human ear. It is common for artists to record to digital and re-record the tracks to analog reels for this effect of "natural" sound. In addition to all of these attributes of tape, tape saturation is a unique form of distortion that many rock and blues artists find very pleasing.

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The earliest reel-to-reel systems used metal wire as a medium (see wire recording), which is robust, but suffers from a number of problems—fidelity is poor, it requires a strong current to imprint the signal onto the wire, it is inconvenient to physically cut and splice to effect an edit, and the wire can kink or even tangle. The invention of cellulose acetate plastic tape coated with iron oxide solved these problems, opening up the use of tape recorders in studios. Wire was also used as a recording medium in black box voice recorders for aviation in the 1950s.

The great advantage of tape for studios was twofold—it allowed a performance to be recorded without the 30 minute time limitation of a phonograph disc, and it permitted a recorded performance to be edited. For the first time, audio could be manipulated as a physical entity. Tape editing is performed simply by cutting the tape at the required point, and rejoining it to another section of tape using adhesive tape, or sometimes glue. This is called a splice. The splicing tape has to be very thin to avoid impeding the tape's motion, and the adhesive is carefully formulated to avoid leaving a sticky residue on the tape or deck. Usually, the cut is made at an angle across the tape so that any 'click" or other noise introduced by the cut is spread across a few milliseconds of the recording. The use of reels to supply and collect the tape also made it very easy for editors to manually move the tape back and forth across the heads to find the exact point they wished to edit. Tape to be spliced was clamped in a special splicing block attached to the deck near the heads to hold the tape accurately while the edit was made. A skilled editor could make these edits very rapidly and accurately. A side effect of cutting the tape at an angle is that on stereo tapes the edit occurs on one channel a split-second before the other.

The performance of tape recording is greatly affected by the width of the tracks used to record a signal, and the speed of the tape. The wider and faster the better, but of course this uses more tape. These factors lead directly to improved frequency response, signal-to-noise ratio, and high frequency distortion figures. Tape can accommodate multiple parallel tracks, allowing not just stereo recordings, but multi-track recordings too. This gives the producer of the final edit much greater flexibility, allowing a performance to be remixed long after the performance was originally recorded. This innovation was a great driving force behind the explosion of popular music in the late 1950s and 1960s. The first multi-tracking recorders had four tracks, then 8, then 16, 24, and so on. It was also discovered that new effects were possible using multi-tracking recorders, such as phasing and flanging, delays and echo, so these innovations appeared on pop recordings shortly after multi-tracking recorders were introduced.

For home use, simpler reel-to-reel recorders were available, and a number of track formats and tape speeds were standardised to permit interoperability and prerecorded music. Reel to reel was still popular through to the end of the 1970s, despite the ubiquitous cassette, mostly because of the superior quality of open reel recordings. Audiophiles are willing to accept the relative fiddliness of open reel tape to gain better quality reproduction. Reel-to-reel tape editing also gained cult-status when many used this technique on hit-singles in the 1980s.

When Ampex broke apart in the 80's, a company named Quantegy Inc. was formed, later becoming Quantegy Recording Solutions in 2004. Quantegy (and formerly Ampex) led the field in reel-to-reel technology, and Quantegy is the only company left making reel-to-reel tape in the world. Quantegy is still located in Ampex's original spot: Opelika, AL.

1 Tape speeds
2 See also
3 External links
4 Reel-to-reel recorder brands

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Tape speeds

In general, the faster the speed the better the sound quality. Slower speeds conserve tape and are useful in applications where sound quality is not critical.

15/16 inch per second (ips) or 2.38 cm/s — used for very long-duration recordings (e.g. recording a radio station's entire output in case of complaints)
1 7/8 ips or 4.76 cm/s — usually the slowest domestic speed, best for long duration speech recordings
3 3/4 ips or 9.52 cm/s — common domestic speed, used on most single-speed domestic machines, reasonable quality for speech and off-air radio recordings
7 1/2 ips or 19.05 cm/s — highest domestic speed, also slowest professional; used by some radio stations for speech programs
15 ips or 38.1 cm/s — professional music recording and radio programming
30 ips or 76.2 cm/s — used where the best possible treble response is demanded, e.g., many classical music recordings

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