All information in these pages is copyright (c) 1989-2003 by Roger Nichols.
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What The Hell's The Dang Deal?
By Roger Nichols
Questions from readers have been piling up for some time now. E-mail, snail-mail,
female, questions from all corners of the universe. The questions this month
center around CD mastering. I will attempt to straighten out a few things
right here, right now.
"I have been sending my final masters to one particular mastering
facility because they say that they are the only place in the world
that can make my 16 bit mixes into HDCD. What the hell's the dang deal."
Signed Twice Bit.
Dear Twice,
There are a couple of issues here. One is the fact that you can not add
more bits to improve your record by playing back your 16 bit master and
recording it into a 20 bit machine. It is like transferring a VHS video
tape to Digital Betacam. VHS tape only has 240 lines of resolution, and
the picture won't improve by copying it to a higher resolution medium. At
this time, the HDCD encoder only allows analog in. This means that you have
to send your 16 bit signal out through a D/A converter, which can slightly
change the sound you thought you had, and then back into the HDCD encoder
through their A/D converters. You have not gained anything, you have actually
lowered the signal to noise ratio by about 1.2 dB and added to the high
frequency grundge that is usually associated with digital audio.
We have mentioned encoding in this answer because the HDCD process is indeed
an encode/ decode process. This means that if your material was 20 bit and
run through the HDCD encoder, you could only get the 20 bit information
back if you own an HDCD decoder or a CD player with an HDCD decoder built
in. Without the decoder, you get less than 16 bits of audio out of the CD,
and because of the extra conversions during mastering, it won't sound as
good as your original 16 bit master. If you wish to have your CD released
in HDCD format, you should mix directly to the HDCD encoder, and then make
sure the mixes are good enough that you don't have to do anything in mastering,
because any further processing will destroy the encoded signal and you will
be worse off than if you just mixed to 16 bit as usual.
One last comment on this subject. HDCD only stores 16 bits on a CD, because
the CD format can only store 16 bit audio. Next year when the audio version
of DVD (Digital Video Disc) is released, you will be able to store 20 bit
audio without encoding and decoding. Your best bet now to get ready for
20 bit is to mix 20 bit onto a Sony PCM-9000, the new Studer Optical Disc
Recorder, or directly into SADiE or Sonic Solutions. After mastering, tell
the mastering facility that you want a 20 bit EQ copy of the final product.
When the high resolution CDs are ready, you have a catalog of 20 bit projects
ready to go without remastering.
"I work for a company that invests in startup companies. We are
currently considering investing $8 million in a company who says that
they have a black box that can be inserted into the digital audio chain
and makes digital audio sound 'warmer'. What the hell's the dang deal?"
signed Deep Pockets
Dear Deep,
First of all, let me say that I really loved your movie with Nick Nolte
and Jacqueline Bisset. Second of all, I will build you the same box for
$7 million. These guys are really pulling your chain. I hear stories like
this all of the time. "You should only work here because we have a
special box that will make any kid that listens to this CD want to do their
homework." Gadgets like this are not going to make your mixes sound
better. You can make digital audio sound as warm as you want. If you take
your final mixes to Doug Sax or Bob Ludwig or Bernie Grundman or Scott Hull
or Greg Calbi, they can warm up your mixes because they know what they are
doing and can tell by "listening" whether a mix sounds good or
not. Guys like these don't need, and probably wouldn't use a magical box
like this. Now, if there was a box that made your record a guaranteed hit
by running your mixes through it, that's another story.
"When I listen to my mixes at home they sound great, but when I
hear them on the radio they don't sound quite as loud as the records
around it. What the hell's the dang deal?" signed Knot Loudenuff.
Dear Knot,
Here is another one of those "black box" deals. One mastering
room I heard about has all of the record companies banging down their door
because they reportedly have a box that will make mixes louder on the radio.
This is simply done with EQ and compression. If your midrange is brighter
and you used more compression, then your record will sound louder. The mastering
guys I mentioned can do this without a black box if you want them to. End
of discussion. The decision here is to decide whether or Knot (sorry, I
couldn't help it) you want your CD to sound any good when the person who
hears it on the radio buys it and tries to listen at home. In Nashville
lately there has been a push to see who can limit their records the most
and have them still remain intelligible. Some of these records are limited
so much that the peak meters and the VU meters read exactly the same.
If you MUST have your record limited, use a digital domain limiter, and
you will be much better off if it is a multi-band limiter like the one in
the TC M5000. Multi-band limiters split the frequency spectrum into multiple
sections. Each section is limited separately so that a loud kick drum won't
make the hi-hat level change. Bottom line is, be careful, you want people
to buy your record and enjoy it at home also.
"I went to get my album mastered and asked whether I should get
a Sony 1630 or a Pre-Master CD to send to the pressing plant and keep
for future re-releases. The engineer told me that '1630s will be around
forever and only the place that cuts the CD-R can play it back'. What
the hell's the dang deal?" signed Dee Pressed.
Dear Dee,
I have had the same thing happen. They told me that CD-R will only play
back on a special machine and you would be locked in to that facility. Without
getting over emotional about it, all I can say is BULL! These guys are idiots,
to put it mildly. The Sony 1630 is a 3/4" video tape format that ALWAYS
has dropouts. 1630 tapes from only a month ago will have dropout problems.
Every time you play a 1630 tape it will have more errors than it did the
time before. Sony discontinued 1630 production over a year ago. The 1630
format will not support 20 bit and 24 bit formats. No more 1630s are being
produced and Sony is trying to set the PCM-9000 as the mastering standard.
It is a fact that CD-R discs will play back on any CD player; the one in
your car, your Walkman, the one in your living room, the one at the CD plant,
and the one at any other mastering facility. A CD-R will not have any more
errors after 1000 plays than it did after the first play. CD-R discs typically
have a much lower error rate than commercially released CDs.
I think that the mastering facility is afraid that you may be going somewhere
else to get your work done, and he has to protect his clientele by producing
fabrications rather than high quality results.
"I want to use 20 bit mixes for my final mixes, but I can't afford
a PCM-9000 or a Sonic Solution system. I use ADATs for most of the tracks
and a friend has a Tascam DA-88 that we sometimes sync up. I know that
DAT machines are only 16 bit, so what can I do? Can I use 20 bit converters
and print 20 bit mixes to my Pro Tools?" signed Ms. Conception.
Dear Connie,
I am sorry to say that at the present time Pro Tools does not support 20
bits. If you have an early Digidesign Init in your system you may be able
to select 20 bit files from Sound Designer, but the hardware will not let
20 bits through. The only way you can do it is to use the Pro Master 20
interface box plugged into and old two channel Sound Accelerator II audio
card. Digidesign says that with the introduction of the PCI buss cards 20
bit will be back in the picture. The first showing of PCI hardware will
be NAB in Las Vegas later this Spring.
If you have 20 bit converters and a friend with a DA-88, then you can store
20 bit mixes with the addition of a Rane Paq Rat. It will split up the 20
bit signal and store it on four channels of the DA-88. When you play back
the audio the Paq Rat will put the signal back together and send it out
as 20 bit AES digital. If you mix to this format, you can play it back 20
bit into the system at any mastering facility where they can then process
your audio in the higher 20 bit resolution. When they get finished mastering,
ask them to print a 20 bit copy of the final masters back out to your DA-88
through the Paq Rat. You will now be ready for the high definition CDs without
having to remaster.
ENUFF
So, ahh that about does it for this round. If you have any pressing audio
or marital questions you would like answered, e-mail me at rnichols@digital-atomics.com
and check out the Web Site with all of my EQ columns at http://www.digital-atomics.com.