Error in Upsampling Certain CDs?


Hello everyone, this thread is about upsampling CD players or D/A converter. I have noticed that on occassion my upsampling D/A does not work to upsample certain CDs, but will work just fine with others. For example, Pink Floyd, the Wall. The upsampling sounds absolutely horrible, the level is increased but there is all kinds of weird distortion and sound. Try disc 2 if you have it. When I swap with another CD there is no problem. Bought the Floyd cd in the '80's. So my question is whether you have found difficulties in upsampling certain music?

- anyone out there notice the same thing or close?
south_park
I've never had any problems with upsampling. Can't recall if have "The Wall" on disc, but if i do, i'll try giving it a spin tonight and see what happens. Sean
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I recently ran across the following text at the Audio Research website (at http://www.audioresearch.com/CD3.htm) in a description of their new CD player-transport, the model CD3:

"While using the latest 24/192-capable Crystal DAC, the CD3 does not upsample, because our empirical research shows sonic compromise is unavoidable due to sample rate manipulation and approximating errors."
Is your CD clean and scratch free?? That may be the problem. I've also had friends tell me that some of their oldest CDs are deteriorating to some extent. THat could easily cause reading errors too.
Phild, that's a great diagnosis, are you a doctor? In 1988 at a frat party my date spilled a beer on a rack of my cd's including this one, the paper inserts to this day are moldy its not that gross). Of course a cd this old is gonna have some scratches, so I cleaned the CD and now it skips on track 1. However, it still has the problems with upsampling, and this is on every track, across the whole disk, on both disks. So either the CD is going bad or there is something else. I have older CD's that were also slimed but which are unaffected. Anyone else?
No...I'm a nurse. That said...what makes you think that upsampling is your problem?? I've read that "upsampling" is very similiar to oversampling. Doesn't that mean that the same data is read 128 times or whatever? It's a method to make sure that the data being read is correct, right?? I don't see how it could cause that problem...not if your DAC is working properly. If it happens on multiple CDs it might be a problem with your DAC, or possibly your laser/transport. The upsampling errors that Key Metric mentioned above shouldn't result in the sort of distortion that you mentioned...they would just sound less *right*. The CD deterioration that my friend experienced happened to most of his original XTC CDs from the 80s (I don't know if they were UK imports or domestic). I also read a story about someone that lived near an ocean(in New Orleans, I think), and they claimed that the salt air was causing corrosion on their older CDs. I have no idea if any of that is true, but no one really knows how CDs will age. Your copy is pretty old. Maybe the beer helped speed up the aging process? (I usually feel quite a bit older the day after I have one pint too many) You might not even be able to see the damage because it's probably taking place in the metal coating...it might not be a visible to the eye. Maybe it's time for you to replace your copy of The Wall with the remastered version? Hell...think of it as an upgrade.
FWIW: I have a copy of the Wall. It is the only disc I own that makes a light turn on my DAC (Parasound DAC1000). If I recall, that light signifies some kind of compression or something in the recording process. It is truly a reference CD. I upsample through an AA DTI-PRO32 and have not noticed a problem. I have owned the old 80's 2 disc set and have owned the remastered version for the last few years. I don't know that upsampling is what is causing your troubles but I know The Wall is the only CD I have encountered that does this. I'll pull out the owner's manual and see if I can't find the exact meaning behind the light on the DAC. BTW: the remastered version is well worth the money - a reference CD.
Treyhoss, thanks! Let me know what you find out. FYI, I have also encountered problems with certain satellite broadcasts on dish network.
South Park,
Sorry for not getting back to you right away. According to the DAC1000 manual: "De-Emphasis LED - Some digital recordings are encoded with pre-emphasis contouring. Your D/AC-1000 automatically recognizes and processes them. An LED illuminates as a beacon for visual confirmation."
I'm not an engineer but that could play a role. As I said, The Wall (both old/new versions) is the only CD that activates this light. That said, it sounds great and well recorded - like most Floyd is:-)This is, however, the only Floyd disc that activates the light and uses this de-emphasis. My guess is Floyd was using some "state-of-the-art" studio electronics (It was recorded in '77/78 I think). What other titles do you have that do this?
Sorry for not getting back to you on this. I do not have The Wall. As such, i was unable to test it out.

Treyhoss' suggestion sounds like the source of your problem. Since this is the only disc that you seem to be having problems with and that is the only disc that he has seen his de-emphasis light energized on, i would not worry too much about it. Sean
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Treyhoss, thanks for the info, you are awesome! Tell you what, I will get a new version of the wall and post if I have problems, since probably the deemphasis of the "emphasis" is the problem. I'll email you with results and also if I find another CD that needs testing. For Sean, I have not had any problem with any other disc, but have rarely experienced the problem with satellite tv, hey, who else out there upsamples their tv to 24/98??? Yeah, its not that much better!
- thanks to all.