dblue Posted September 4, 2002 Author Share Posted September 4, 2002 mdeneen, I stand corrected on exactly how redbook audio works. I was running on false info about how CD audio works. One thing I like about this forum, is that there is always someone who knows more about a specific topic. ------------------ "May your mind be like water and mold to many things." -Bruce Lee Quote Link to comment Share on other sites More sharing options...
Deang Posted September 4, 2002 Share Posted September 4, 2002 Hey guys, how about them Cleveland Browns Quote Link to comment Share on other sites More sharing options...
Mallette Posted September 4, 2002 Share Posted September 4, 2002 Good analysis, and all the more reason to dump your CD's to HDD where this uncertainty will end. If it sounds good the first time, it isn't going to change. I also burn CD as wav files for backup. However, you did not mention the fact that part of the scheme vastly increases the likelyhood of accurate decoding, the C1 and C2 layers. This redundancy goes a long way towards insuring a good and consistent rip, or good play if the player is good enough. Dave Quote Link to comment Share on other sites More sharing options...
mobile homeless Posted September 4, 2002 Share Posted September 4, 2002 If it sounds good the first time, it isnt going to change? After all this, I would have thought you were beyond such a statement.kh Quote Link to comment Share on other sites More sharing options...
Mallette Posted September 4, 2002 Share Posted September 4, 2002 Geez, MH, we seem to fly right past each other. OK, so I am looking at a wav file right now in HEX, trying for the life of me to see how so much as a digit could get changed during playback. I've granted than extremely small variations due to the data streaming scheme may make each redbook playback inconsistent (probably inaudible on a high end CD player) with another. However, once extracted it is never, never, never, never gonna change on an HDD as long as that HDD lives. Even then, copy to another will yield a perfect likeness, with a CRC checksum to prove it. Maybe in your eyes it is going to be wrong...but it is going to be consistently wrong in exactly the same way each and every play. What in this so offends your sensibilities? Dave Quote Link to comment Share on other sites More sharing options...
Mallette Posted September 4, 2002 Share Posted September 4, 2002 You don't even need a soundcard to rip. Only the file format is changed from redbook "form" to wav. The software handles error correction. Once this is done. the file will never change so long as the system is functioning. The quality of the output after this is entirely dependent upon the soundcard and the rest of the chain. Dave Dave Quote Link to comment Share on other sites More sharing options...
Mallette Posted September 4, 2002 Share Posted September 4, 2002 You are correct, sir. Except that the CDROM drive serves only to transfer the redbook data to the CPU. No soundcard involved at all. After that, it's stored on HDD and played back through the Card Deluxe. I've about 140 CD's stored as untranscoded wav files, all with automatically generated (via web access to CDDB) playlists with names, titles, and timing. I could set up a playlist with over a month of music if I wanted. As I cannot afford the kilobuck plus required to get a really good CD player (nor do I understand any longer just why I'd want to do that, since Card Deluxe is only 400.00 and records 24/96 to boot), I do not have any kind of "CD player" in the system. I rather doubt that CD's are capable of sounding much better than I am hearing them now. I'd found them suitable only for automobiles and background music in the past, and I don't do much of either. The few LP's I've recorded to 24/96 are the first recordings I've made of LP's since I used 15ips R-R and DBX encoding that I've found satisfying. All for a lousy 400.00. Yeah, I know us financially challenged music lovers shouldn't get deals like this...but it happens. Dave Quote Link to comment Share on other sites More sharing options...
mobile homeless Posted September 4, 2002 Share Posted September 4, 2002 ummmm...... yeah, well. Not so sure about all this. And surely not sure you need over $1000 to equal the sound there. Christ, the computer is one of the WORST places for audio to emerge, considering the horrible RFI, awful PS, etc etc. The list goes on. I might be getting a sound card in the near future to transfer all my reel to reels from the past 25 years so we'll see. Computer cards have supposedly come a long way. The ideal of CDs only fit for autos etc is a bit much, and I am sure no CD fan. kh This message has been edited by mobile homeless on 09-04-2002 at 06:55 PM Quote Link to comment Share on other sites More sharing options...
fini Posted September 4, 2002 Share Posted September 4, 2002 I suppose the chicks stopped reading this thread long ago, guys, so don't hold back. fini Quote Link to comment Share on other sites More sharing options...
Mallette Posted September 4, 2002 Share Posted September 4, 2002 MH: The Card Deluxe folks seem to have done a heckuva job of minimizing or eliminating contamination from the computer. The worst noise is from the fans, though this is a pretty quite computer and any music at all covers it. I am not hearing any issues at all...but then that could just be my hearing. I really would love it if you'd give CDeluxe a try. As I said, it's provided LP transfers that I can listen to without wanting to jump up and put the record on. That's a first. As I have enormous respect for your experience and opinion, it would be great to hear what you have to say. "The ideal of CDs only fit for autos etc is a bit much, and I am sure no CD fan." Hey, don't hang that on me. I was simply pointing out that that was my personal experience with nothing more than auto CD players, discmans, and 150.00 Sony changers to go on. I find myself listening to quite a bit more CD's with the Card Deluxe. Dave Quote Link to comment Share on other sites More sharing options...
Audio Flynn Posted September 4, 2002 Share Posted September 4, 2002 Great thread guys! It sums up alot of things I have read about the Reed Solomon analytical work over the years. It is very timely because I just told my wife last night that someday I would have to imbibe in the technology of a used Mark Levinson or Meridian CD player. I would definitely have to live with a unit for months to determine if CD playback technology made by obsessive complulsive guys who live and breath audio as much as I do my carreer path, have it figured out! I nearly blindly believe that a few select high end companies can deliver a CD Playback product that is a near equal of vinyl playback that my PA system beat up 42 year old ears could deem equivilant in quality. Things I would like to try before the real expensive stuff... 1. Monarchy DIP anti jitter device before my MSB Link DAC. 1a. Balanced patchcords 2. Card Deluxe in a used P3 Pentium box with Plextor drives. 3. A used CEC Transport. As I paraphrase from Ray... every device or interaction between devices all have measurable differences with the proper test equipment and time to investigate; can the listener hear the differences remains the ongoing question. Quote Link to comment Share on other sites More sharing options...
Audible Nectar Posted September 5, 2002 Share Posted September 5, 2002 OK, you guys are in a technical area in which I have very very limited knowledge, but I'll try anyway. Ripping WAV files from redbook CD's is a very inexact endeavor. To my knowledge, the only truly bit perfect software that exists for ripping bit perfect copies of WAV's is Exact Audio Copy (I've also heard that the Plextor software comes close). It reads and rereads each sector on a disc up to 70 times to insure that it gets it right, then reports on any errors encountered during the rip. The accuracy of the rip can then be verified by using checksums - a hexidecimal "fingerprint" if you will - that will be exactly the same as the original if the rip is bit perfect. Using usual ripping software yields imperfect results. You can compare by burning a set of WAV's to CD, then rip the copy and check to see if the checksums match on both sets of WAV's. Another cool trick: those WAV's can be compressed by a LOSSLESS compression scheme known as "Shorten". Shorten will compress the file to about 55% of the original size. When the compressed file is unzipped, the resulting WAV will be identical to the original WAV. We swap the Shorten files across the web, then unzip them for burning (since those shorten files DO have the built in error correction, as well as the smaller file size). We can also check known sources of live concerts against a database of checksums, to ensure that the "bloodline" is perfect - no flaws vs. the original as the copies are made from generation to generation. My understanding of the difficulty with WAV's is this: they don't have their own built in error correction that most data files do (I'm not sure as to specifics, this is where my knowledge is a bit grey). It has to do with the way WAV's are "packed" datawise vs. normal computer data. What I do know is this - the checkums do not lie. Using the checksums will tell you if the ripping scheme is proper and bitperfect. For free access to these tools, go here: Etree link Then go to "software". This scheme is used in the digital trading community to verify that exact copies are being traded. I will point out that this software is not used for illegal purposes - the Etree site is established for the purpose of distributing music from "taper friendly" bands - those who allow the free trading of live concert material. More about the CardDeluxe: This card is excellent at combating noise from the computer box. Mine is hooked up by optical (can be done with the optional bracket) as well as analog - to two different tape loops (one digital, one analog). Great recording results both ways - I can't tell the difference between source and hard drive copy. The DAC's on the CardDeluxe are very clean and pure (wonderful for digitizing analog sources). Quote Link to comment Share on other sites More sharing options...
Mallette Posted September 5, 2002 Share Posted September 5, 2002 dndphishin: THANKS for the links! Have downloaded all and can't wait to try. I've been using CDex very successfully, but having the extra confidence check will be very useful professionally. Also looking forward to shn, as I've been storing my CD's as wav files...more bang for the gbyte! Audio Flynn: Please give CDeluxe a try and report. I've been fighting a tough battle to convince skeptical audiophiles that this is the best non-analog deal there is. Dave Quote Link to comment Share on other sites More sharing options...
dblue Posted September 5, 2002 Author Share Posted September 5, 2002 mdeneen, Now I'm a bit confused. If the cd-rom is doing the 'translation' from redbook encoding to WAV, then how come when I rip a cd to my HD, it is exactly the same size (in bytes) that it was on the CD. In other words, if I rip a 632 megabyte CD onto my Hard Drive and store in WAV format, it only takes up 632 megabytes of space. Someone help me make sense of this. Db ------------------ "May your mind be like water and mold to many things." -Bruce Lee Quote Link to comment Share on other sites More sharing options...
dblue Posted September 5, 2002 Author Share Posted September 5, 2002 mdeneen, Yes, I have a program called Nero Burning Rom (good stuff), and when you have the program running, It will show you exactly how big the disk is. Also, if the disk is inserted into your CD-ROM, you can right-click on the drive icon, go to properties, and see how much data is on the disk (in bytes). ------------------ "May your mind be like water and mold to many things." -Bruce Lee Quote Link to comment Share on other sites More sharing options...
Mallette Posted September 5, 2002 Share Posted September 5, 2002 Question: Will the shn software handle 24/96, and will the winamp shn plugin play it? These suckers are BIG, and I've quite a few LP's to record. Dave Quote Link to comment Share on other sites More sharing options...
dblue Posted September 5, 2002 Author Share Posted September 5, 2002 Well, put it this way. I have a CD that plays 78 minutes of music. An 80 minute disc holds approx. 700 Megabytes of data. So we'll say that this 78 minute disc has about 680 megabytes of data on it. Now when I rip this disc to my HD in WAV format, it takes up the exact same amount of space on my HD. 680 Megabytes. This is what I am confused about. ------------------ "May your mind be like water and mold to many things." -Bruce Lee Quote Link to comment Share on other sites More sharing options...
dblue Posted September 5, 2002 Author Share Posted September 5, 2002 Also, when I was referring to right clicking on the CD-ROM drive's icon, I was talking about in the operating system, not the burning software. Even on a linux OS, a full CD will show itself to make up 700 MB's of data (assuming it is an 80 minute disc). Plus the meter on the burning software is actually showing you how much space this disc or data will take up if burned to another CD, in which case, if it was audio, would have to be encoded to REDBOOK to work in a player. If I take a 5 MB wav file, and burn it onto an audio CD, it only takes up 5MB on that disk. If I take 80 minutes worth of WAV files, they'll take up 700 megabytes on my HD, or the entire CD. ------------------ "May your mind be like water and mold to many things." -Bruce Lee Quote Link to comment Share on other sites More sharing options...
Audible Nectar Posted September 5, 2002 Share Posted September 5, 2002 Dave, I don't know the answer to either question. You could try to shorten the 24/96 and see if it works. There's no info on the Softsound website (Shorten folks) about this, but it does leave one to believe that something other than 16 bit can be used. I've only used these tools on 16 bit 44.1khz. I don't know about shnamp either. Again, I would try it out. In the case of all the Etree software, I would make sure they work with 16/44.1 first, so you know you are using the tools correctly. Then try them on the 24/96. Don't forget the MKWact (interface to shorten and unshorten files, plus create and use MD5 checksums). It will make the process much easier. Quote Link to comment Share on other sites More sharing options...
dblue Posted September 5, 2002 Author Share Posted September 5, 2002 Mdeneen, I've figured it out. I just did an experiment. I just took a copy of the Obrother soundtrack, and looked at just the audio files on the CD. (60:31, 611 MB). Now, I ripped these files into WAV onto my HD, and they take 610 MB (close enough). I then realized that the WAV format is nothing more than redbook audio. Microsoft came out with this format for windows 3.1, and then there were no other formats for digital audio ( I don't think so anyway ). So basically, when you record a WAV file, it rips the raw data from the CD to your HD. Then, when you play it back, the OS, (or any player software such as Windows media, winamp, etc) apply the EFM demodulation and CIRC error correction in real time, and play it back through the sound card. So when you rip a WAV, you are getting an exact duplicate of what's on the CD. And since the software runs the demodulation and error correction, the only limits you have in sound quality are your DAC converter (which in most sound cards is pretty darn good), and the noise and interference your computer may put off. Oh yeah, and the speaker/amplifier system. There you have it. ------------------ "May your mind be like water and mold to many things." -Bruce Lee Quote Link to comment Share on other sites More sharing options...
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