Tape Editing
Cut editing (also known as destructive editing)
consists of physically cutting magnetic recording tape, removing an unwanted
portion and rejoining the recording tape with a special adhesive backed splicing
tape.
Monophonic and stereophonic 1/4 inch tapes were traditionally edited
in this way. Cassette tapes can be cut edited but it is difficult to locate the
precise edit point. The technique is sometimes useful for retrieving damaged
cassettes.
Multitrack tapes (4 or more tracks) are not cut edited.
Removing a section of 1/4 inch tape
- Play the tape until you hear the first cue, that is, the sound at the
beginning of the section you intend to remove.
- Put the tape recorder into edit mode. (See the operator's manual.)
- Rotate the tape spools by hand with the tape against the replay head,
(usually the one on the right).
- Using a chinagraph pencil, mark the tape at the beginning
of the section to be removed.
- Mark the tape at the second cue, e.g. at the end of the section to be
removed.
- Pull the tape away from the replay head and lay it in the guide of the
editing block,
oxide side down.
- Line up your chinagraph mark with one of the diagonal slits in the editing
block.
Choose the 450 (45 degree) slit for a stereo recording,
the 600 slit for a mono recording or the 900 slit if you
are removing clicks.
- Cut the tape by running the corner of a single-sided razor
blade along the slot.
The corner of the blade should run along
the bottom of the slot in the editing block.
It does not matter that the
corner of the blade becomes blunt because that is not the part of the blade
that slices the tape.
- Now cut the tape at the other chinagraph mark
- Remove the unwanted section of tape but keep it safe in case you need to
replace some or all of it
- Slide the two ends of the tape together in the editing block.
The two
cut ends should just butt together. There should be no overlap and no gap
between the ends.
- Cut about 2cm of adhesive splicing tape. Touch one end of
the splicing tape on to the side of the razor blade, so that it lightly sticks
there.
- Use the blade to transport the cut length of splicing tape to the editing
block.
- Stick the length of splicing tape over the butt join and press out any air
bubbles with your finger nail.
- Remove the magnetic tape from the splicing block.
- Play the tape at a good listening level and listen to the edit point.
As the edit passes the replay head there should be
- no change in the level (loudness) or quality of the foreground speech,
music , e.t.c.
- no change in the level or quality of the background noise
- no change in the rhythm of the speech or music
Sticky tape, razor blades and leaders
- Take care to stick the splicing tape on the non-oxide side of the tape.
Modern recording tape usually has a matte finish on the outer, non-oxide
side.
- Touch the sticky side of the splicing tape as little as possible with your
fingers.
- The razor blade should be sharp.
- Razor blades can become magnetized if they are dropped or encounter
magnets.
A magnetized blade will cause audible "plops" as edits go pass
the tape recorder's replay head.
- Keep razor blades in a labelled container, such as a shallow screw topped
jar.
- Never hand a razor blade to anyone.
It's safer to place the
blade on a flat surface and let the borrower pick it up from there.
- A leader is a length of coloured tape, (the same width as
the recording tape) which is spliced onto the recording tape to indicate
beginnings and endings.
Use
- white or yellow before the beginning of a programme
- yellow for intermediate spacers
- red at the end of a programme
Professional studios may have
their own 'in house' colour codes.
Editing is a skill that only comes with practice. Ear training is as
important as manual dexterity.
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Copyright (c)1997 D. Barnes
Music Technology Handouts/ Tape
Editing /November 1997