[hosted by Taylor Hales]
The first thing that you want to do before you even put your tape onto your machine is
take stock of what you have in terms of documentation about what the contents of the tape and its
technical spec.
Your key sources of information are going to be looking at the tape, itself, and, kind
of, determining how it's partitioned with leader.
And also, more importantly, the tape box, which will have ideally a box label on it
or will have some hand-written notes about the format and such.
And, if you're lucky, there'll be a track sheet or some other piece of paper on the
inside of the box that has some information on technical spec and the contents of the tape.
In the ideal transfer, you will have tones that will allow you to reproduce the conditions
under which the tape was recorded;
you will have calibration tones;
and you will have ample documentation about the technical spec of the tape.
But in the case of most of the transfers that we get, we have no tones and little or no
information on documentation.
In which case, we just have to rely on some kind of educated guesswork, and we have to
calibrate off of a calibration tape.
And I'll walk you through how you might get the best transfer possible in those conditions.
The first two things you want to take stock of are:
the format of your tape, so you can change your machine to accommodate that tape,
and the presence of any noise reduction, so that you can enable noise reduction on your
machine, or patch in any outboard noise reduction decoders.
Guessing the format of a tape when you don't have documentation can be kind of tricky.
If you play back your tape and you notice that the VU meters on pairs of channels move
identically, you've probably guessed the format of the tape incorrectly by a factor of two.
In this case, I'm going to play a tape that's a mono tape on a stereo headstack, and you'll
notice that both of the VU meters move identically.
So, this is a mono tape, and if this machine is set up for stereo, I should change over
the format to mono.
[voice of Jay McKnight: "MRL calibration tape. AES Equalization at 355 nW/m, fringing compensated"]
Conversely, if you are playing a multi-track tape, and you notice the tracks or sound sources
are married together that you wouldn't expect to be married together, you've probably guessed
the format incorrectly, and you need to increase the channel count.
So if you play a tape back on an 8-track machine and your kick and your snare, for example,
are married together in one track, try playing that tape back on a 16-track machine, and
see if you get separated kick and snare.
Spool up your tape.
And the first thing that we're going to try to determine, which we should figure out pretty
quickly, is the speed of the tape.
We'll know pretty instantaneously whether or not we've guessed the speed correctly,
because if the machine is set too fast we'll hear everything in squirrel voices. And if
the machine is set too slow, everything will be excruciatingly slow.
So I'm gonna guess that this tape is at 7 1/2 ips and hit "PLAY",
and we'll just see how we did.
So as this tape is playing, I realized that I guessed the wrong speed. It's playing at
double-speed, so I'm gonna just switch the speed of the machine down to 3.75 ips.
I also noticed that the audio's playing backwards, which means that i guessed that this tape
was stored heads-out, but it was actually stored tails-out.
So, if you notice that your audio's playing backwards, you just have to flip which side
of the machine you spool your tape onto, so I put this onto the supply side - I need to
put it on the take-up side and wind it back and then the audio will play correctly.
As I'm looking at this tape, I also am seeing on my VU meters that my signal level, my repro
level, is significantly too low.
We don't have any test tones on this tape, so I'm going to calibrate this machine based
on an MRL calibration tape, and whatever calibration level this machine is currently set to, I'm
going to increase the repro gain 6 dB so that those peaks are hitting at about 0.
The last piece of technical information that you need to gather about your tape is the
equalization that it was recorded with.
And in this case, if you don't have any documentation that tells you what the EQ is, you're just
going to have to make an educated guess.
At 30 ips, you only have one choice, there's only one EQ at 30 ips and that's the AES EQ.
If the tape was recorded at 15 or 7 1/2 ips, you're gonna have to guess whether it was
NAB or IEC.
And the most germane piece of information to making that judgment is simply where that
tape was recorded.
IEC EQ was dominant in Europe, and NAB was dominant in North America.
So, try to gather whether the tape was recorded in North America or Europe, and just set your
EQ to IEC if it was recorded in Europe (as far as you know), or NAB if it was recorded
in North America.
Once you've gathered the full technical spec of the tape, you can go ahead and align your
machine based on an MRL calibration tape to that spec.
And if you need help calibrating your machine, you can go ahead and click the link here.
And then all that's left to do is re-spool your tape and patch the outputs of your tape
machine into the inputs of your digital recorder.
And hit "PLAY" on your tape.
And hit "RECORD" on your digital recorder.
And that's it!
So thanks for watching, and we'll see you next time.
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