Head-Fi.org › Forums › Equipment Forums › Sound Science › Bit depth and sampling frequency explained
New Posts  All Forums:Forum Nav:

Bit depth and sampling frequency explained - Page 2

post #16 of 21
Everyone is overlooking the major benefit of increased sample rate here. I know the conversation went towards bit depth, but I can not stress enough that Nyquist assumes an ideal low-pass filter in order to remove the sampling artifacts that are mirrored in the spectrum. Increasing the sample rate allows you to use a much better filter with a more gentle roll-off which avoids putting oscillation and ringing in the audio spectrum.
post #17 of 21
Quote:
Originally Posted by emmodad View Post
from another thread, here's a pointer to some useful and not-overly-technical reading (from Pohlmann, Principles of Digital Audio)

http://www.head-fi.org/forums/f133/2...ml#post6161651
don't post much on head-fi since I don't really have the time, but I read it as frequently as I can. And I found that there is a lot of misunderstanding about the effects of bit depth and sampling frequency. Even in the "24 vs 16 bit myth exploded" thread. In fact most of the info is wrong.
I am a master student in EE, and have specialized in communications. Including lots of courses in Fourier analysis. Now I work in speech processing/recognition, so I am more qualified than most people here.
I will try to explain in layman terms.
post #18 of 21
Please do. But you aren't the first to declare the information in that and similar threads is plain wrong. I've yet to see any of the claimants make a convincing argument as to why they are right and the others are wrong though. Also, you aren't the first to cite advanced degree studies in EE or similar as credentials. So, not saying you are wrong, but am interested to see what your arguments are. And I admit I am skeptical you are right, but willing be shown the errors of my ways.
post #19 of 21
Quote:
Originally Posted by mabus627 View Post
...and I found that there is a lot of misunderstanding about the effects of bit depth and sampling frequency. Even in the "24 vs 16 bit myth exploded" thread. In fact most of the info is wrong.....
Quote:
Originally Posted by Arjisme View Post
Please do. But you aren't the first to declare the information in that and similar threads is plain wrong. I've yet to see any of the claimants make a convincing argument as to why they are right and the others are wrong though.

@ mabus627: agreed, there has sadly been a significant amount of misleading info posted wrt digital signal processing fundamentals, esp regarding sampling theory and quantization. the "24 vs 16 bit myth exploded" thread is a notable example.

Hence the link provided to Pohlman (commentary and link to free sample on books.google: http://www.head-fi.org/forums/f133/2...ml#post6161651) for access to a technically-correct intro... one which is reasonably digestable for those who have been smart enough to avoid an EE education (me, I was deluded enough to go the BS/MS/Doctoral studies EE path, and started working in pro audio equipment dsp hardware design in the early-80s. should have stayed an actor, different type of fun).

Principles of Digital Audio (Pohlman, Amazon.com: Principles of Digital Audio (9780071441568): Ken Pohlmann: Books) is well worth reading (and buying) for those looking to get a reasonable (and correct) foundation in concepts of signal processing, data conversion, etc. as applied in the audio world. good info on quantization error, quantization distortion and how that leads to performance metrics.

Another good option: many good resources in general on the Analog Devices website, and their Data Conversion Handbook is a fine choice (Amazon.com: Data Conversion Handbook (Analog Devices) (9780750678414): Analog Devices Inc. Engineeri: Books -- excellent bibliographies also, great resources to many of the seminal papers of signal processing theory, quantization error, etc.)


@ Arjisme: no arguments required. scientific and engineering fact concerning sampling theory and quantization is simply that: fact.

more helpful than "argument" is to help people to learn, and directing them to actual fundamental resources gives them the tools which can be used and later revisited as reference (as opposed to burning time in the all-too-common thread rhetoric and defensive outpourings ie by those prolific posters who finally get around to admitting that they don't understand the underlying math of signal processing, or the underlying technology in converter design)

try these: Pohlman (see links above); Understanding Digital Signal Processing (Lyons, http://www.amazon.com/Understanding-...p/0131089897); fundamental texts on sampled-data systems ie Discrete-Time Signal Processing (heavy stuff, but definitive -- Oppenheim/Schafer Amazon.com: Discrete-Time Signal Processing (3rd Edition) (Prentice Hall Signal Processing) (9780131988422): Alan V. Oppenheim, Ronald W. Schafer: Books)


teach a man to fish....
post #20 of 21
Seconding emmodad and mabus627. I think most people have just given up because Gregorio expends so much effort in defending himself that he could've read a book in that time and done everybody a favour. And you know, when you argue something in a way that leaves you no possible way of changing your mind without disasterously losing face, it's time to change the way you argue.

Quote:
Originally Posted by emmodad View Post
one which is reasonably digestable for those who have been smart enough to avoid an EE education (me, I was deluded enough to go the BS/MS/Doctoral studies EE path, and started working in pro audio equipment dsp hardware design in the early-80s. should have stayed an actor, different type of fun).
Aint that the truth. For anyone else out there who was unfortunate enough to have learned EE fundamentals from high school or even from a less than stellar college/university: "Electricity" Misconceptions Spread By Textbooks. There's some good stuff on transistors and capacitors there too.

I'd like to offer some more resources but I think what you've already got there is a great selection.
post #21 of 21

another good signal-processing info resource

a portion of a very good Analog Devices overview seminar is available through a link in the globaldsp March e-Newsletter

some of you may find the globaldsp site (registration required; link: DSP Store - the largest on-line DSP database) to be an interesting general resource for news in the realm of digital signal processing.

the ADI tutorial contains (relatively) easily-absorbed info on sampling / quantization of analog signals, and converter functionality / performance.

"An Introduction to Sampled-Data Systems" (Kester, Bryant) can be accessed from

http://www.dspstore.com/$Newsletter/newsletter.asp?Month=March2010

look for the above-referenced title at bottom of page; download link is for a pdf file

if you do not wish to register on dspstore, the direct document link from ADI is

http://www.analog.com/static/importe...gnal_Sect2.pdf
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Sound Science
Head-Fi.org › Forums › Equipment Forums › Sound Science › Bit depth and sampling frequency explained