Can you give me some guidelines
on how to supply a source for mastering ?
1: Don't record too loud. There is a popular myth that says
you are only getting the most from digital if "all
the lights are on" - ie. the signal is clipping or peaking
at 0 dB. This isn't true. Allow at least 1 or 2 dBs headroom when recording
- any higher and you risk digital distortion, which can cause
major problems at mastering. Some manufacturers use less than
perfect metering on their machines, so we recommend you avoid
allowing your recording to peak at zero, just in case there
are over-levels which the meters aren't showing.
Engineers & producers - even if your customers are demanding
a really "hot" reference copy, please make a clean
copy for us to master from and then lift the level for the
2: Always use dither. Dither is a special kind of (very quiet)
noise, added to digital files when they are processed, to
reduce truncation errors. Believe it or not, a 16-bit digital
file recorded or processed with dither can reproduce sounds
an extra 6 dB quieter than one without. Undithered recordings
can start to sound brittle, edgy, grainy and harsh. We feel
many complaints about early digital recordings result partly
from poor implementation of dither. If in doubt, whenever
you have any processing to do, use dither.
3: Avoid unnecessary processing. Every time a change is made
to a sound digitally, it is done with a certain accuracy.
Even 32-bit calculations incur a small number of errors, and
these may affect the sound, especially if many changes are
made. So, for example, if you adjust the volume of your material,
and then change your mind, don't process it again to reverse
the change - go back to the original. Think carefully about
whether you need to make a change at all - it's even a good
idea to avoid copying except where absolutely necessary.
In addition, some software doesn't include proper dithering
functions, and so degrades the sound - see point 2 above.
4: Avoid analogue copying. If your sources are digital, and
you make flat copies digitally, you can maintain their quality
indefinitely. But every time you make an analogue copy, a
small amount of quality will be lost. Also watch out for computer
soundcards. Even those with digital inputs may apply sample-rate
conversion to your music (for example the Soundblaster Live
series) which has the potential to degrade the sound, especially
if it's done several times.
5: Be organised, but don't worry about the order. Unless
you're having a copymaster, we can put your tracks in the
right order at the session, but it's a good idea to make sure
you know which mix you want and which tape it's on, for example,
to save time in the session.
6: Avoid "over-cooking". Decent audio equipment
is much more easily available than it was, and there is a
temptation to try out all the options. In particular, there
are many tools offering "mastering" functions, like
compression and normalising. We recommend you leave this until
the mastering session. It is possible to achieve excellent
results with these tools, but why bother when you're paying
us to do it ? By all means bring us an example to listen to,
but wherever possible we prefer to work from "clean"
7: Always keep a safety copy, and bring it to the session.
When digital sources fail, they often can't be repaired, so
always keep a second (digital, flat) copy of everything, and
bring it along to the mastering session, just in case.
8: Leave "topping and tailing" to the mastering
session. We will be loading your tracks to a digital editor,
so we can perfect any fades and/or crossfades for you then.
Sometimes mastering can bring up subtle details of the mix
which weren't audible before, and it's a shame to have them
chopped off too abrubtly. You can always experiment before-hand
and bring in a copy for us to refer to.
1: Don't make the gaps too short. Some DAT machines are very
untidy dropping in or out of record, with the result that
mutes or glitches can appear. To avoid accidentally clipping
the starts and ends of your tracks, we recommend not using
the first two minutes of DAT tapes at all, and waiting for
at least 4 seconds after you've started recording on the DAT
machine before starting to play the audio in. If you're having
full mastering done, we can fine-tune the gaps for the best
possible effect anyway.
2: Avoid long tapes. Longer tapes are thinner and more prone
to stretching and other damage. It's best to use the shortest
tape you can get away with.
3: Have your machine serviced regularly. Just like analogue
tape machines, DAT recorders can get dirty and worn, and alignments
can drift. It's well worth keeping your machine in good condition.
These tips apply mainly to people using computer or hard-disc
based systems to create CD-Rs. For standalone CD-R burners,
the points already mentioned above are the most important,
but some of these may also apply:
1: Always use dither , if you haven't already. If you are
working in 16-bit, and have followed our general advice, your
files will already be dithered. But if you use 20, 24 or 32-bit
files, then either before you make your CD-R, or as it is
written, you should apply 16-bit dither. See general point
2 above. Some applications, for example Adaptec JAM and earlier
versions of Cubase do not include dither. In Wavelab it is
switched off by default.
If you are compiling your CD-R from other CD-Rs & CDs,
with no level changes or processing, there is no need to use
2: Allow a PQ offset. When you decide where to put the track
markers on your CD-R, leave at least a third of a second before
the music comes in. Some older players don't play track starts
accurately, and might chop the beginning off. If we're mastering
the audio for you, leave even more time, to avoid any risk
of clipping ! Also a clean sample of any background noise
makes de-hiss operations more efficient, if they're needed.
3: 4x-8x is usually best. CD-writers are getting faster and
faster, but we still get the best results for audio from most
machines at four-times speed.
4: Try to find out whether your CD-R burner "likes"
your brand of CD-R. Different burners react differently to
different makes of CD-R. See if you can get a recommendation
from your manufacturer. In general, well-known brand-names
perform better than cheaper, unbranded varieties. The internet
can be a valuable source of information on this subject.
5: Always listen to your CD-R. Just because a computer says
a disc has been made correctly, doesn't guarantee it will
sound perfect. Many sources arrive with us for mastering full
of clicks and dropouts which our customers didn't know were
there. It's always worth taking the time to listen carefully
to your master all the way through before mastering.