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Gear / Technical Help => Ask The Tapers => Topic started by: deadahead93 on April 22, 2009, 05:29:57 PM

Title: 24 and 16 bit?
Post by: deadahead93 on April 22, 2009, 05:29:57 PM
Hi all.
I'm new to the site and this is my first post.

Quick ?
Just got the new Tascam DR-07 and this is the first recorder that I have owned that has had a 24bit and 16bit setting. I'm not too sure which to record with... I was just on the Archive looking at some of the new DEAD shows from this tour and one source was Crystal Clear but said: Recorded in 24 bit, not for CD burning

Most of what I want to record, I want High Quality and to be able to burn to disc... Sorry for the nOOb of a question, but if someone is willing to point me in the right direction I'd be very Grateful! Sorry if this has been discussed B4.
Cheers to all, and I love your site! 8)
Title: Re: 24 and 16 bit?
Post by: tailschao on April 22, 2009, 05:37:28 PM
Rule of thumb is to record in 24 for extra dynamic range and lower noise floor - ability to boost volume more in post without static. Then dither to 16 for CD burning.
Title: Re: 24 and 16 bit?
Post by: dhora on April 22, 2009, 05:39:16 PM
Welcome to the site!

If you record at 24 bit, you can not burn the files directly to an audio CD because an audio CD is 16 bit.  You would first need to dither your recording via software down to 16 bit / 44.1 kHz and then burn it to disc. 

If you have the ability to record 24 bit and then convert it to 16 bit later for listening on audio CD, I would suggest that route because then you have the higher quality master recording at 24 bit.

You should be able to find some threads in the Computer Recording Help section (http://taperssection.com/index.php/board,5.0.html (http://taperssection.com/index.php/board,5.0.html)) if you need some help on how to dither down from 24 to 16 bit.
Title: Re: 24 and 16 bit?
Post by: Chuck on April 22, 2009, 05:41:08 PM
Yes, recording in 24 bit is a more complicated workflow.
Do read-up on it before you jump in.
Title: Re: 24 and 16 bit?
Post by: deadahead93 on April 22, 2009, 05:45:40 PM
Thanks for the welcome and the super quick response! You guys are awesome...

I will let you all know how the new Tascam holds up in the field. Gonna try to stealth the Dead show in LA and going to set up a full rig for the Joshua Tree Music Fest (and anything else that pops up).  http://www.joshuatreemusicfestival.com/ (http://www.joshuatreemusicfestival.com/)

Anyone else hitting up either of these two events?
Title: Re: 24 and 16 bit?
Post by: zzrck on May 22, 2009, 11:23:02 PM
you always want your master recording in the highest quality ou can get it in.
usually you will have to edit it and track it out before transfering it to cd anyway .
i edit all my stuff in magix audio cleaning lab , it will take 24 bit and transfer it
into any format you want to , including 16 / 4400 for cds
Title: Re: 24 and 16 bit?
Post by: ghellquist on May 23, 2009, 02:11:52 PM
Well assuming they tell you the truth at page 97 of the user manual:

S/N Ratio (LINE IN> LINE/OUT) 87dB or more.

As this number is below 96dB you will gain absolute nothing going from 16 to 24 bits.

The only rationale going above 16 bits is to lower the noise floor. This allows you to turn down the amplification a bit which gives you a larger margin against occasional strong sounds. You would typically add this volume once at home in your post-processing. Well, unless the noise floor goes down by going to 24 bits (contradicted by the S/N number beeing less than 96dB), all you do is use more memory space and creating hassle for yourself.

Now, remember that 16 bits carefully used are plenty good, no CD record ever produced has more, most has less.

// Gunnar
Title: Re: 24 and 16 bit?
Post by: chris319 on May 26, 2009, 11:50:01 PM
Quote
you will gain absolute nothing going from 16 to 24 bits.

Absolutely not true! At 24 bits there is far less quantization error over that dynamic range than at 16 bits. Whatever gain adjustment you perform digitally will work far better at 24 bits.
Title: Re: 24 and 16 bit?
Post by: Scooter123 on May 27, 2009, 01:20:57 AM
I've never noticed a difference, except the files are half the size on 16b making them easier to work with.  My ears can't tell the difference.

That being said, I try to record in 24b.
Title: Re: 24 and 16 bit?
Post by: Dede2002 on May 27, 2009, 10:22:52 AM
I've never noticed a difference, except the files are half the size on 16b making them easier to work with.  My ears can't tell the difference.

That being said, I try to record in 24b.

Please, do it. You won't regret. ;)
Title: Re: 24 and 16 bit?
Post by: DSatz on May 27, 2009, 10:47:07 PM
chris319, when the noise in a channel is already well below the level of the noise being fed into that channel, you won't get any distinct audible benefit from reducing the channel's noise level still further.

The concept of quantization error which you state with such admirable firmness is unfortunately not correct. If it were, then a midrange audio tone (say, 1 kHz) recorded at a very low level (say, -80 dBFS) on a 16-bit system would have significant harmonic distortion--overtones that shouldn't be present. This distortion would increase still further if the level of the signal were to decrease, and ultimately the sine wave would turn into a square wave as only a single bit (the "least significant bit") is toggled on and off. On a 24-bit system, the distortion at any given recording level should be considerably lower, since more bits are being used to characterize the level of the signal at any given moment; more details of the original signal are preserved, the "stairsteps" are smaller, the curves smoother, etc., etc., etc. ...

Does that description sound familiar? It's based on the way that many people imagine that digital audio works. And it's provably mistaken. If you set this all up as an experiment, and listen to and/or measure the results (which almost anyone on this forum can do in about ten minutes), NONE of the predictions hold up.

Distortion doesn't generally increase at lower recording levels, for example (that being mainly a matter of converter linearity, which is separate from "resolution"). Low-level tones don't become more square-wave-like, if you look at the analog output of the recorder (which is what counts, since we only hear analog).

The sad thing is, this was all demonstrated publicly and explained mathematically 25+ years ago by now--but people who don't know about it are still "correcting" other people who really have it right.

--best regards
Title: Re: 24 and 16 bit?
Post by: su6oxone on May 27, 2009, 11:40:41 PM
DSatz
Thanks for your expert input as always.  Regarding 16 vs 24 bit though, what is your opinion overall for the purposes of audience audio taping at concerts? 
Title: Re: 24 and 16 bit?
Post by: Chilly Brioschi on May 28, 2009, 12:34:20 AM
Recording at 24bit will at the least allow you to run levels a few db lower, still capture at least 16 bits of sound, and therefore reduce the chances of distortions from going over.

Back in my day we used to make cassette recordings with the rough equivalent of 8bit and we were happy!      ;)

Also, if file size/handling isn't an issue, then the higher resolution recording will prove to be less "future-proof".

As always, and sadly, the people who sell gear know that we buy specs, even when they aren't fully qualified and reasonable.
We used to buy playback amplifiers rated at "peak input power", which was often much more than double of what an amplifier actually delivered! It was sales bullcrap, and the practice of using the rating has been banned by the FTC.

Don't expect a similar pushback that resolved that issue to ever occur for the 24 bit vs. 16 bit question.



In my practical use:

24/196    - when speed and storage is without limit.

24/88.2    - when I am archiving, such as during a concert recording  (this makes for a better CD version later)

16/44.1     - when I am recording practices, local acts, or spoken word, or if I am truly in a storage crunch, which isn't likely these days


I hope that helps



Title: Re: 24 and 16 bit?
Post by: svenkid on May 28, 2009, 01:24:28 PM
http://24bit.turtleside.com/
Title: Re: 24 and 16 bit?
Post by: DSatz on May 28, 2009, 11:26:24 PM
su6oxone, I never deliver anything but 16-bit material (usually CDs) to clients, but I record 24-bit when I have any doubt about the sound levels that might occur. I'm usually the only person recording a given event, and 24-bit recording means not having to take risks to get the levels "just right."

The only real disadvantage is the reduced recording time on a given-size memory card and the extra time needed to reset levels and dither to 16 bits when I make CDs for people. To me those are OK tradeoffs, though.

--best regards
Title: Re: 24 and 16 bit?
Post by: su6oxone on May 29, 2009, 12:16:19 AM
su6oxone, I never deliver anything but 16-bit material (usually CDs) to clients, but I record 24-bit when I have any doubt about the sound levels that might occur. I'm usually the only person recording a given event, and 24-bit recording means not having to take risks to get the levels "just right."

The only real disadvantage is the reduced recording time on a given-size memory card and the extra time needed to reset levels and dither to 16 bits when I make CDs for people. To me those are OK tradeoffs, though.

--best regards

Thanks as always DSatz!
Title: Re: 24 and 16 bit?
Post by: Jeremy Lykins on May 29, 2009, 01:35:48 PM
su6oxone, I never deliver anything but 16-bit material (usually CDs) to clients, but I record 24-bit when I have any doubt about the sound levels that might occur. I'm usually the only person recording a given event, and 24-bit recording means not having to take risks to get the levels "just right."
The only real disadvantage is the reduced recording time on a given-size memory card and the extra time needed to reset levels and dither to 16 bits when I make CDs for people. To me those are OK tradeoffs, though.
--best regards

Just out of curiosity, what sample rate do you record at?  Is there much difference between 48, 88.2, 96, etc.? 
Title: Re: 24 and 16 bit?
Post by: taperwheeler on May 29, 2009, 03:47:15 PM
Well assuming they tell you the truth at page 97 of the user manual:

S/N Ratio (LINE IN> LINE/OUT) 87dB or more.

As this number is below 96dB you will gain absolute nothing going from 16 to 24 bits.

The only rationale going above 16 bits is to lower the noise floor. This allows you to turn down the amplification a bit which gives you a larger margin against occasional strong sounds. You would typically add this volume once at home in your post-processing. Well, unless the noise floor goes down by going to 24 bits (contradicted by the S/N number beeing less than 96dB), all you do is use more memory space and creating hassle for yourself.

Now, remember that 16 bits carefully used are plenty good, no CD record ever produced has more, most has less.

// Gunnar

Where can I find this user manual?  The one with my dr-07 doesn't have 97 pages...Some kind of joke?

Nevermind...saw it on pg. 95...
Title: Re: 24 and 16 bit?
Post by: datbrad on May 29, 2009, 04:20:45 PM
su6oxone, I never deliver anything but 16-bit material (usually CDs) to clients, but I record 24-bit when I have any doubt about the sound levels that might occur. I'm usually the only person recording a given event, and 24-bit recording means not having to take risks to get the levels "just right."
The only real disadvantage is the reduced recording time on a given-size memory card and the extra time needed to reset levels and dither to 16 bits when I make CDs for people. To me those are OK tradeoffs, though.
--best regards

Just out of curiosity, what sample rate do you record at?  Is there much difference between 48, 88.2, 96, etc.? 

I can't speak for Dsatz, but I run 48 khz. 88.2 is often used because the resampling calculations are evenly divisible when going to red book 44.1 khz. However, for video based audio formats (not DVD audio) 48 and 96 are the standards, and no video formats that I am aware of are compatable with 88.2 khz.

96 khz samples frequencies up to 48 khz bandwidth, which is out of the range of human hearing, most if not all microphones, and only a few instruments can generate tones at that high range, that still cannot be heard by humans. 48 samples up to 24 khz bandwidth, which is more than enough to capture every sound perceptable by even a 1 year old child with the best hearing he will have his entire life.

While 24 bit clearly has definable advantages for mastering, sampling rates over 48 khz are using a great deal more memory space on your storage device, with little if any sonic advantage for the amount of space used.

YMMV