Do you really care about 24/96?

[ZiggY!]

I don't really care about anything higher than CD quality right now. If I can't master my songs or have them mastered what is the use in recording at a higher rate. Can't hear it anyway.

hmmm... its not about the sound its about the headroom...

READ THIS EVERYONE!!

Slackmaster wrote:

If you were simply recording one stereo track and not processing it in any way, then recording at 16/44 or 24/96 wouldn't really make much difference.

But that's not what we're talking about. You're going to be doing a serious amount of "math" with the raw data files. The higher the resolution your raw tracks are at the better sound quality you end up with in the end. Consider a graphics artist doing artwork that will end up on the web. Just because the final distributable image will be rendered at 72dpi doesn't mean that the artist started at 72dpi. On the contrary, he/she was probably working with resolutions many times that.

The second part of the answer lies in "headroom."

Digital headroom is not the same as analog headroom, because in the digital realm nothing exists above 0db. However, higher the bit depth, the lower the levels you can record at without sacrificing quality. Remember that the decibel scale is logarithmic, which results in an interesting relationship between resolution and sound level.:

Every 6db of gain requires one more significant bit. Thus, in a 16bit system, -96db to -90db is represented by one bit; -96db to -84db is represented by 2 bits; and so on and so forth until you conclude that -96db to 0db is represented by 16bits, or 65536 (2^16) discrete values. Likewise in a 24bit system -144db to 0db is represented by 24bits, or 16777216 (2^24) values.

That's all pretty obvious, but now think about this. The range -96db to -90db in a 16bit system is represented by *one* bit, which yields two discrete values (1 or 0). Now, try to imagine what a waveform looks like when each sample can only consist of two voltage levels! But of course who cares, right? It's way down at -90db which is pretty hard to hear. Well, let's keep doing the math. The range -90db to -84db is represented by how many discrete values? 2^2 - 2^1 = 2. Again, two discrete values. The range -84db to -78db is represented by 2^3 - 2^2 = 4 values. The range -78db to -72db is represented by 2^4 - 2^3 = 8 values. Let's make a picture:

_____________________ -96db
0000 0000 0000 0000 = 0
0000 0000 0000 0001 = 1
_____________________ -90db
0000 0000 0000 0010 = 2
0000 0000 0000 0011 = 3
_____________________ -84db
0000 0000 0000 0100 = 4
0000 0000 0000 0101 = 5
0000 0000 0000 0110 = 6
0000 0000 0000 0111 = 7
_____________________ -78db
0000 0000 0000 1000 = 8
0000 0000 0000 1001 = 9
0000 0000 0000 1010 = 10
0000 0000 0000 1011 = 11
0000 0000 0000 1100 = 12
0000 0000 0000 1101 = 13
0000 0000 0000 1110 = 14
0000 0000 0000 1111 = 15
______________________ -72db



Continue on, and you soon realize that your prime tracking range of -6db to 0db is represented by 2^16 - 2^15 = 32768 discrete values. Can you now see why people using 16bit systems recommend trying to stay in the yellow? If you track at -12db to -6db, for instance you just halved your resolution, and your waveform is represented by just 16384 discrete levels.

Now a 24bit system looks like the following. Remember that 0db is our hard limit, thus when you increase your dynamic range by increasing the number of bits you use, that range is found at the bottom of the scale:

______________________________ -144db
0000 0000 0000 0000 0000 0000 = 0
0000 0000 0000 0000 0000 0001 = 1
______________________________ -138db
0000 0000 0000 0000 0000 0010 = 2
0000 0000 0000 0000 0000 0011 = 3
______________________________ -132db
0000 0000 0000 0000 0000 0100 = 4
0000 0000 0000 0000 0000 0101 = 5
0000 0000 0000 0000 0000 0110 = 6
0000 0000 0000 0000 0000 0111 = 7

Hmm, looks very similar to the 16bit illustration, except that we've sort of shifted everything way down to -144db. That's true, and at first it might not seem like a big deal, because who cares what happens at -144db? Nobody does. What's actually interesting is what happens up at the TOP!

In a 24bit system, the range 0db to -6db is represented by 2^24 - 2^23 = 8388608 discrete values. Continue on with the boring math, and you'll find that you don't even get into 16bit resolution until you hit -48db (ah, 6db * 8 extra bits = 48db!)!

That means that speaking purely from a resolution standpoint, tracking at -42db to -48db in a 24bit system is equivalent to tracking at -6db to 0db in a 16bit system! Of course our electronics aren't quite that good, and we still have converter self-noise (coming up next) to contend with, thus nobody would actually want to track that low. However, in a 24bit system you don't have to pound the yellow to maintain signal resolution like you do with 16bit....and if you do, you're simply rewarded with exceptionally higher resolution which can result in better math yeilding better end results.

Here's a fun example. Take any 16bit audio file and decrease the volume on it by 90db. This will effectively squash the sucker into just a couple bits. Apply the volume change, reopen the file (if necessary), and turn the volume back up by 90db. "ZZZZZZZZZZgarblegarbleZZZZZZZZZgarble" Well what did you expect? Do the same thing with a 24bit file and what do you end up with? Well, you basically get a 16bit version of your 24bit file...and that ain't so bad

The third part of the answer lies in noise.

Noise is an electronic problem that creeps into our digital world. No converter is going to be perfect, thus way down in lower sound level ranges you're going to have noise. Yick. In the extreme case, take something like an old Soundblaster 16. The noise floor (where the noise level sits) on those suckers was in the range of -40 to -30db! Extremely damaging! In the opposite extreme case, you might find that the noise floor in a very professional 16bit system is down in the -84db to -90db range, which is much more acceptable. But in a properly designed 24bit system, the noise floor can be way down in the -102db to -96db range, thus giving you the FULL 96db of dynamic range that was once promised by 16bit systems, and it can do so at much greater resolution!

Now I should put a disclaimer up. The most important thing about any converter is how it sounds. You want what you hear back out of your recording system to sound as close to what went into it as possible. Converters *damage* incoming sound in a very audible, unwanted way. A cheap card like a soundblaster damages the sound quite severely. A better card like an m-Audio Delta 1010 will still damage the sound in an audible way, but to a much less extent. The point I'm getting at is that it is possible to have 16bit converters that are less damaging than 24bit converters. In fact, I would suspect that a very pricey apogee 16bit converter would sound much better than the converters found in the $600 Delta 1010. Your DSP would sound worse on the 16bit data, but it would probably be worth it to preserve those sources that you've worked painstakenly to capture. The rule of thumb, though, is that 24bit converters really aren't that big of a deal to manufacturers anymore...thus on your better soundcards and converter boxes made today, you're just going to see 24bit converters...that's all there is to it.

Slackmaster 2000


i hope he didnt mind me posting this...

 

[moley]

Very good point about headroom, actually.

I'm using a VS2480 - which has 56-bit internal processing

 

[Jamie Jukosky]

Wow, I learned a lot from that. I had no idea that it was a headroom issue and that all that data squashing was going on. Cool.

 

[Light]

why resample and dither? even at the mastering stage. unecessary.

I hate too say this, but I agree with Numbnuts on this one. I have yet to hear a sample conversion which sounds good. Many (if not most) mastering engineers do sample conversion by going to analog, and then reconverting to digital. The generation lose is less severe than the problems with sample conversion.

By the way, I do NOT have the ears of a god of any sort, but I can still hear the difference in 24/96. I can also say that the converters need to be f**king amazing before it is worth it. The really nice Apogee converters will do, but nothing less. Nyquist converters are amazing.

By the way, for mix down, I always liked 1/2 " analog two track. Digital ain't even close yet. I wish I could afford it these days.

Light

"Cowards can never be moral."
M.K. Gandhi

 

[beezelbubba]

I've only recorded in 16/44,so I have nothing to compare it to.I'm much more focused on the music and the writing,so as long as it sounds relatively clear,I don't worry too much.I must admit the only reason I haven't upgraded to 24/96 is that I can't afford to.I'm sure there's a noticable difference.

 

[ecs113]

i care about 24/88.2 and 24/44.1

 

[Troy Dubb]

44.1 sounds GREAT! Until you A/B with 2 inch tape. Ive never heard 96 A/B'd with 2 inch. Its got to be better than 44.1

 

[sjoko2]

With all due respect to most of the posters........
It appears that those who have NOT HEARD the difference between 16 bit, 24 bit or 44.1 - 48 - 96 etc. will respond that "it sounds good"

Be asured there is a huge quality difference between lower and higher bit-rates as well as clock speeds. To denounce this is simply going straight against reality.

Headroom is the name of the game, and also the reason why it is now possible to record digital to a higher quality than previously possible in the analogue domain.
Not, I'm saying its is POSSIBLE. But only if you use top end equipment, which is extremely expensive.

 

[pipelineaudio]

"44.1 sounds GREAT! Until you A/B with "
48k

 

[jmproductions]

2 cents follows:

I debated this issue for a few years and once I got some 96/24 equipment I came to the conclusion that it sounds better. But not very much better, not enough to bog your resources down with all that data; of course I, like most people, can't afford the hi-end converters. If you think about it pretty much anyone who will be listening to your stuff will be listening to it on CD. Period. The format will be around for a long time to come. How many people do you know have a DVD-A player and then how many of them can tell the difference between 44.1/16 and 96/24?

I am mixing in an all-digital environment so 44.1/24 just makes the most sense for me. A format conversion sounds like crap and seems pointless in the reality of a CD dominated world. You guys that are tracking in higher res, then analog mixing down to tape makes good sense and I wish I had the equipment. I bet it sounds great.

 

[sjoko2]

2 cents follows:

I debated this issue for a few years and once I got some 96/24 equipment I came to the conclusion that it sounds better. But not very much better, not enough to bog your resources down with all that data; of course I, like most people, can't afford the hi-end converters. If you think about it pretty much anyone who will be listening to your stuff will be listening to it on CD. Period. The format will be around for a long time to come. How many people do you know have a DVD-A player and then how many of them can tell the difference between 44.1/16 and 96/24?

I am mixing in an all-digital environment so 44.1/24 just makes the most sense for me. A format conversion sounds like crap and seems pointless in the reality of a CD dominated world. You guys that are tracking in higher res, then analog mixing down to tape makes good sense and I wish I had the equipment. I bet it sounds great.

It does sound VERY much better, like night and day, in the correct environment. Please note that one of the prime advantages of working with high resolution audio comes to the fore when you apply effects or manipulate the audio.

 

[tvaillan]

24/44.1 for me. Computer is slow (1.2GHz) and so I can't afford a boost in sampling rate.

24 is great cause I can track a singer without using an outboard compressor. Given the dynamic range at which i'm recording, (whispers to yells) , given my noisy mixer faders, and given the fact that I'm too poor for a good compressor, 24 bits is perfect . It allows me to apply compression after the fact and spares me from riding my fader during the performance.

 

[geekgurl]

It does sound VERY much better, like night and day, in the correct environment. Please note that one of the prime advantages of working with high resolution audio comes to the fore when you apply effects or manipulate the audio.

Originally posted by pipelineaudio
"44.1 sounds GREAT! Until you A/B with "
48k

Hi guys: Can you clarify something for me? I've heard that recording at 48k was a waste if you're mixing down in digital because the calculations to get from 48 to 44.1 degraded the sound beyond what it would have been just recording and mixing down all in 44.1 anyway. Obviously, if one can master to high-quality analog 2-track thru excellent D/A converters this is a non-issue.

But what I'm wondering is, do you think it's possible for an all-digital mixdown that's converted from 48 to 44.1 to sound as good or better than something recorded exclusively in 44.1? If so, what would allow that? Is it a certain software, or a hardware requirement, or both (like a TDM system)?

 

[tvaillan]

now that's a great question geekgurl. I can't wait to see the answer. I've been wondering that myself . .. cause if 48 is proven better, then, I'll change my CPU and go for it.

 

[pipelineaudio]

My mastering engineer usually goes back to analog for most of the mastering, so it doesnt matter what sample rate I bring it in at.
For cheaper projects lately that I know I will have to " master" myself, I have been trying 44.1, but it sounds to me like a blanket thrown over the sound, and a lot of EQ's just become nonresponsive

 

[sjoko2]

Hi guys: Can you clarify something for me? I've heard that recording at 48k was a waste if you're mixing down in digital because the calculations to get from 48 to 44.1 degraded the sound beyond what it would have been just recording and mixing down all in 44.1 anyway. Obviously, if one can master to high-quality analog 2-track thru excellent D/A converters this is a non-issue.

But what I'm wondering is, do you think it's possible for an all-digital mixdown that's converted from 48 to 44.1 to sound as good or better than something recorded exclusively in 44.1? If so, what would allow that? Is it a certain software, or a hardware requirement, or both (like a TDM system)?

There is no ( I mean NO) question that higher rates are better, without exception. In other words, if you have the possibility to record at 96, 48 etc. that this would always be a preference over 44.1. If you have the possibility to record at 24bit instead of 16 bit, the same goes.

Where you could screw such a thing up is in the final stage, when you would convert your stereo mix to CD quality. But....... there are so many programs either built into software now, or available cheaply, that can do the job to a reasonable quality, that not being able to do so properly is no longer a valid argument.

I should perhaps point out that to most engineers CD quality has always been something that sucked major. When CD's were first launched we had big issues with hearing our good sounding analogue masters converter to thin sounding sandpaper quality sound. Over time, when clocks and converters improved, various standards of encoding became available, things improved slightly, but CD quality has never sounded acceptable - period.

Now we are at a point where we can record to very high standards in the digital domain, with headroom far exceeding what was possible with the best analogue, but we're still stuck with a below quality medium on which most people listen.

Furthermore, it is not just the end product that sounds better when recorded at higher rates. Key benefits are derived from any kind of processing and summing you do at higher rates. Everytime you use an effect, a processor, bounce or sum channels, you will get the benefits. As such, the effects are cumulative.

So in conclusion, the tale that calculations to get to 44.1 from 48 lead to...... etc., you can firmly put that in the land of bullshit

 

[LI_Slim]

So I'm reading from all of the above that it matters if you have professional studio quality equipment, and it does not matter if you are a typical home recorder. Yes?

 

[littledog]

my system can record as high as 24/192, but I still record at 24/44.1.
Why? Storage and archiving.

I may be convinced if I someday find my stuff sounds incredibly better at high sampling rates, but in the meantime sessions containing 60-80 GB of data (per session) scare the crap out of me. Since I usually have a half dozen (at least) projects going simultaneously, I'd be spending my whole life dumping data on and off drives. And the price of archival media????

 

[sjoko2]

If you use some firewire drives for archiving, its both cheap and fast, as a 150 Gb drive is now available for under 300 bucks. Say you have a 10Gb song, it will take you approx 15 minutes to make a copy. If you use fiberchannel drives you can back-up 80GB of data in about 10 minutes or less.

We never have anything other than the session we're working on on the drives, as you cannot take a risk of corrupting the session you're working on as well as other's work in case of data failure.
So..... to solve that problem, all sessions are automatically written to 2 drives simultaniously, and at the end of each session the system does a data check and shuts down. Each artist pays for one drive, which is still cheaper than having to buy the 2" reals "like-as-what-they-hadto" in the olden days.

 

[littledog]

Sjoko -
I agree about the economy of firewire, I don't know if every one of my clients would agree to pay even $300 for a back-up firewire drive for archiving. I guess it's not THAT much, but compared to a DDS4 tape or two, it seems like a lot. I'm also not sure that a firewire drive qualifies as a stable semi-permanent archiving format.

I'm not arguing your point - it's a decent solution that's obviously much faster than tape back-ups - but it still raises problems. I'm swapping sessions constantly between three firewire drives totalling about 320 GB with my recording drive (36GB ultraSCSII). Even with 10-20GB sessions I seem to spend an inordinate amount of time organizing and backing up data.

Right now I can't even conceive of quadrupling the workload.