DLF

I'm not jumping on anything, honest. My snake-oil aside was because I have seen hi-fi salesmen in action using psychology to influence their victims. Can you hear how the guitar is better? (um no but now you mention it), start tapping their feet and nodding their heads when a track is played on the preferred kit. We are all vulnerable to such influences. On this thread the suggestion is that you need a really revealing kit to hear the differences. Well that must influence the results, who wants to admit their beloved system or their ears are a bit rubbish! There is no evil being perpetrated on this thread though and we may find a technical explanation, it's just that we haven't eliminated psychology yet and I can't think of any other test I can do since I can't hear a difference. Edit: If you can identify the files reliably then the next thing to look at is probably the software player and see if it does something wacky.

Jkeny "Don't be so quick to call what you can't explain as the imaginings of fools - I know I can't meet up with you to let you hear the differences but they are there & it makes me want to investigate why, not to doggedly hold onto my views and say anybody who doesn't agree with them is being fooled. Seen as you brought up bias - I would expect you to show a more un-biased approach." Do you mean me? Whoa there, you aren't a fool for hearing differences. My bias, if you like, is that I know how easily fooled I am. It could be I can't hear differences because I think there shouldn't be. My hearing may not be good enough, my system not good enough. However, for my experiment I used something that has no bias and has perfect senses. I used a piece of software. It could find no differences between the files. If I edit a 'bit' in one file it spots the difference so I know it can't be fooled. It doesn't even know the files contain music. If you think this test is flawed then lets try something else but I don't know of a better way of proving the files are identical.

@jkeny How about trying again a little more scientifically.

This is fascinating stuff, it just shows how easily fooled we are. It is also serves as a warning about how vulnerable we are to purveyors of snake oil because of this.

"Edit 2: I will post the differences as I hear them if anybody wants me to - it might be another way of reducing (or not) some possible variables of the playback system i.e if others hear the same differences between the tracks even though they have completely different playback systems then the focus must be on the files themselves and something inherent in the files!" I have just downloaded the Love over Gold files and they are bit for bit identical.

Well, you could start by describing the experiment you conducted for you to conclude they sound different. How did you eliminate bias? How many times could you correctly identify each file?

"Just catching up in the pub". A few atoms must have rearranged themselves in the process I'll wager .

"Also, it seems likely that what you are hearing from these files may have also degraded slightly during transmission." Well, if they 'degraded' lets see. The md5sum of the files I downloaded a few thousand miles across, various routers, servers and finally wireless is 5e4af86de7079b5173ff70d2327bf054. If they have degraded then we would all get different values. This is what happens on my system. I have three files downloaded from you. They are obviously on different parts of the hard drive and an individual 'blocks' of a file may even be scattered all over the place. If I use a program called cmp to compare binary files, each file is read into memory and compared. cmp shows no difference. I used a program called md5 which reads a file into memory and produces a checksum. The checksum is identical for each file. I finally use iTunes which reads a file into memory and plays it. I can't hear a difference between each file. The common denominator between all three programs is that the mechanism by which the file is read is provided by the operating system. I even copied a file onto a USB memory stick and repeated the experiment. So, on my system, the operating system can reliably read a file and present identical data to cmp, md5 and iTunes wherever it is stored on the hard drive or even a USB stick. In your case you have used an md5 equivalent and it creates the same checksum wherever the file lives. This means any other piece of software on your system (i.e. your player) can also reliably read these files because, again, it uses the same mechanism provided by the operating system. What do you think is happening that makes the files sound different on your system? Do you suspect your player of taking identical data and somehow screwing things up? Maybe try a different player because file I/O seems to be working fine for you.

"I think all has been said in this thread on identity. We have wild theories, guesses and some theories that might have something to do with this phenomenon. Have you listened to the files? I know it seems kind of stupid ... But hey the result might be, that you get mad! ;-)" Well as I recall, the first wild theory was the files are different due to differences in the cd/bd drives. Someone produced identical M5 checksums and the theory evolved that it is theoretically possible for different files to produce the same m5 checksum. I have compared them bit for bit and they are indeed identical. "I have repeatedly listened to the files. I can now easily identify the differences in Sound. Of course I might imagine them, so I experimented with different drives, different ripping programms and repeatedly produced bit identical files which sound different. I sincerely wish I would not have found out about this, because now I am asking myself: do i have to rerip my library. You might think, that is paranoid. I would say this is audiophil. ;-)" If you hear differences in sound you need to start investigating what happens at playback time. Your rips are fine.

Thanks Bob. To continue playing, what am I supposed to do with this 3M tape?

"All 3 HDDs and both the Pioneer DVR111 and LG BluRay GGW H20L. Also on the SMPS case , where much of the vibration originates." Well the vibration isn't an issue with the Pioneer DVR111 and LG BluRay GGW H20L because they produced identical files. Are you saying that when you play back a file it sounds different depending on which hard drive the file is read from?

Well I searched for 3M 2552 and got nothing. Which drives, the drives holding the CD you are ripping or the drives you are storing the ripped files on?

SandyK "You will not find differences between these files by normal techniques" Sandy, each file is identical bit for bit. SandyK "People who have heard these differences report that later files appear to have what appears to be a slightly improved noise floor, possibly due to the reduced vibration(?)" Reduced vibration of what? I suggest you stop looking for technical reasons you hear differences and examine the psychological ones. Now people know the files are identical I suspect the reports of audible differences will reduce. You aren't mad, simply playing the same track twice can notice detail you haven't noticed before. Add in the power of suggestion and away you go. It just shows how easily fooled our senses are.

'Track4.wav', 'California Girls.wav' and 'California Girls 2.wav' are all identical. If you hear differences then you need to look at something other than the ripping process.

The files are identical.