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First off, please don't flame me. My question is not intended to elicit emotional responses, but rather simply obtain technical/factual information from inmates who I know are far more advanced than I am on this.I am getting in iPod as a gift because I spend a great deal of time on airplanes. I have tried listening directly from my laptop, but it is bulky, inconvenient and mine doesn't buffer enough so it pauses a lot in the middle of the music. And it sounds like crap anyway. So I am to be assimilated - resistance was futile.
Last night I began ripping lots of audiophile classical CDs onto my laptop iTunes to begin downloading to the iPod itself. I know there are various settings that can be tweaked for ripping, but what is the best setting for the highest quality? I changed the frequency 48Mhz, but is there anything else I can do? And I assume that since my laptop's CD/DVD in not an SACD, I am not ripping the SACD layer of hybrids - just the redbook, correct?
Thanks for your help and understanding.
Follow Ups:
Apple Lossless vs. AIFF or WAV:For audiophile listening with associated equipment I use Apple Lossless. You could choose AIFF if using a Mac or PC or you could choose FLAC (another compression format that is lossless) or WAV on a PC. Personally, I have a Mac and use Apple Lossless on a NAS (Networked Attached Storage). I have a SONOS wireless music system that streams the music from my NAS to my Meridian DSP5200's. The speakers take a direct digital (Coax) input as the DACs are built-in. I have also ripped a few selections to AIFF and steam those using the same system to see if I can hear a difference. I also compared the original CD using a CD player/transport. Honestly, after driving myself nuts, I can't hear a difference...and in therory shouldn't be able to.
What may make a difference in playing back Apple Lossless or any other compression format or even ripping AIFF files and playing those back from a computer or hard drive may be the error correction. iTunes has an option to use error correction for importing (under preferences/advanced settings). According to an article I read (sorry, I can't remember where) using error correction when ripping in any compression format is preferred as it corrects most issues with the CD before writing to the hard-drive. This may account for some that do hear a difference between Apple Lossless and AIFF vs. using a CD player or digital transport.
Apple Lossless and other lossless compression formats don't actually remove bits to do the compression. Rather, they temporarily represent redundant information (1's and 0's) by reprenting them in some form of mathematical equation much like zipping a file. So the file is compressed for storage, but uncompressed to it's original format for playback. Stereophile and Macworld have performed tests on the output of the Apple Lossless file vs. the AIFF file and found they were bit for bit perfect to the origianl stream coming from a CD player's digital out.
Bottom line in my opinion is that the original encoder may introduce issues if not implemented properly (error correction) and that may be where some hear a difference between a lossless compression stream vs. AIFF or WAV. My 2 cents.
Don't get an iPod. Once you do that, you are forever locked into Apple's plans to take over the downloadable music world. Find a feature comparable Zen, or SanDisk, or iRiver, or any one of a 100 other mfgrs. products and go with one of those. You'll get more features for your dollar and you won't be locked into Apple's iTunes fiasco. Go to this site for more info. than you can shake a stick at:http://www.dapreview.net/news.php
The previous advice about getting some replacement earbuds is a good one. I'm not so sure that you need to go all the way up the food chain and get the Shure E5Cs (approx. $500!!), but their E2Cs and E3Cs sound pretty damn good for less than $150...
Oh yeah, finally - be sure to get a shock absorbing case for that puppy. You WILL drop it and it WILL break if you do not shroud it in something.
-RW-
...I have had my 60Gb iPod for over a year and love it.I don't know the capacity of yours, but I would agree that if you want the best compromise between sound quality and the amount of music, you have to use Apple Lossless.
Since you are recording from your own CDs, if you notice any deficiencies in the playback (I did on mostly older recordings which were not that great to begin with), you can re-record that piece in AIFF (PC) or WAV (Mac).
Also, you will need higher quality earbuds to appreciate your hi-rez recordings. I recommend the Shure E5c's. They also cancel noise which is great on an airplane.
"I changed the frequency 48Mhz, but is there anything else I can do?"Changing the frequency to 48 kHz is not a good idea if your original media is CD. If you stay at the resident frequency of 44.1 kHz, the data should transfer "bit perfect" to the iPod, and will sound cleaner overall.
I only use WAV and AIFF non-compressed formats, by the way. I've yet to hear "lossless" compression that I thought was truly lossless.
to save eveb a bit more space I rip background music at 256 and it suffices.
You do not have to change the frequency. leave it on automatic/
nick
I find the Apple Lossless to attenuate inflections and vibratos by the performers. It was kind of spooky when I tried it.
Todd,Can you please describe the hardware/software setup that you used to conduct the comparison of Apple Lossless file playback performance versus CD?
Thanks
Apple lossless is totally lossless, the decoded file matches bit for bit the original CD. With a hex editor you can do this test that proves it.
1. Take any 16-bit .wav file and import it into iTunes (you can rip it from a CD with iTunes)
2. burn it to a CD
3. re-import it from the CD using apple lossless encoding
4. reconvert it to a .wav file
5. use a good hex editor to calculate the CRC (checksum) of the two .wav files, they will match exactlyA CRC is a cyclic redundancy check, it uses nonlinear division to divide the file by a (usually 32 bit) number and returns the remainder, the likelihood of the files CRCs matching if the files are not identical is 1 chance in 2^32, or 1 chance in ~4 billion so you can have reasonable confidence that audio files with identical CRCs are truly identical. Interestingly there are very very few CD ripping/burning programs that do not change the audio, iTunes is one of the few that is totally bit perfect, as long as you use lossless files.
Yes, I know that files ripped using Apple lossless result in output that's bit perfect compared to the original source file. That's why I'm rather incredulous that an Apple lossless file can be audibly different from the original. It would be most illuminating if Todd could share some details regarding the methodology he used for his listening test, but while I'm curious about what his answer could be, I'm not going to indulge in speculation.
> > an Apple lossless file can be audibly different from the original.It can't. It can only be alleged due to open-loop subjective listening tests.
HowdyDoesn't that depend on whether the decompressing causes untoward effects in the downstream components, say noise on the power supply, buffers late for the DMA, etc.? After all we still hear people giving advice to not have too many other apps, drivers, etc. running when you are playing audio. Granted in an ideal world with ideal implememtations these things wouldn't be a problem, but practically speaking they often are and reputedly can cause audible effects. (I say reputedly since I don't listen to music from my PC very much and have no personal experience with Apple lossless.)
-Ted
"Doesn't that depend on whether the decompressing causes untoward effects in the downstream components, say noise on the power supply, buffers late for the DMA, etc.?"Given that even a low-powered device like an iPod can decode an Apple Lossless encoded file, the overhead associated with this task is very low indeed. For current PCs and Macs, with their brute power, it would be trivial.
"After all we still hear people giving advice to not have too many other apps, drivers, etc. running when you are playing audio."Yes, but we need to be specific here about what we're dealing with. The issue here is that high-overhead tasks (such as anti-virus scanning and DVD video playback or encoding) will consume significant CPU and memory resources, thus making the performance of other background tasks suffer as your computer literally bogs down from the load. The key thing to note here is that Apple lossless decoding by itself is not a highly computationally intensive task (far from it) but if you are multi-tasking many other apps or running some other job(s) that heavily taxes your computer's resources, then your computer's overall performance will be negatively impacted. The fact that your audio playback performance can suffer as a result is one of the symptoms, but not the cause.
I think that if you wanted to test whether lossless compression (and lossless compression alone) causes audible differences in playback compared to the original source file, one way would be to run a double-blind test in which both files are streamed from the hard disk of the same computer (acting as a transport) to feed a DAC. Any way you do it, you would have to play back both files in the same system using the same transport and media, otherwise you have too many variables that can influence the result.
HowdyI was just pointing out the fallacy of Greg's post:
"> > an Apple lossless file can be audibly different from the original.
It can't. It can only be alleged due to open-loop subjective listening tests."
In any case if you can hear a problem with differing CPU loads then there is a problem with your setup and the specifics of the amount of load don't matter that much. Unfortunately experience tells us that CPU load is often audible. There are reports here of people that indeed did A/B tests with lossless compressed vs. uncompressed with all other variables the same. As always the people who don't believe there is a difference don't accept that the experiments are controlled enough and the ones that do believe there is a difference don't care about anyone else's experiments :) Anyway I did my experiments before the IPod, I don't have an IPod and I don't really care :)
-Ted
By the way, I should mention that my interest in Apple Lossless stems from my own attempt to build a computer-based music server using a Mac and iTunes as the engine. My choice of hardware and software is based simply on personal preference -- I just prefer to deal with Mac OS rather than Windows. On top of that, I've chosen to encode my files in Apple Lossless in order to achieve an optimum balance between sound quality and storage efficiency. In my own [admittedly crude] experiments, I've been unable to detect any audible difference between streaming music in Apple Lossess format compared to native WAV format when both were played directly off my hard drive and passed to my outboard DAC. The conclusion I've come to is that lossless compression results in output that is both quantatively and qualitatively equivalent to the original. I personally find it very gratifying when the brain and the ears are in agreement, but that's just my $0.02. ;)Cheers,
O
HowdyFrom what I've seen OSX has a pretty nice audio stack. It was a lot harder when we wrote a hard disk recorder for Win 3.0 :) I think a lot of people don't really know what it takes to do good audio in a PC and overlook a lot of the details that matter. When I hear a system that has artifacts of any sort under any CPU load I know that the designers are in over their heads...
-Ted
Hi Ted,"In any case if you can hear a problem with differing CPU loads then there is a problem with your setup and the specifics of the amount of load don't matter that much. Unfortunately experience tells us that CPU load is often audible."
Yes, and when it happens it manifests itself as clearly audible dropouts and "stuttering". However, it should be mentioned that this can happen whether you're playing back compressed audio, uncompressed audio, or video for that matter. Therefore it appears to me that we're talking about two separate topics.
a) The audibility of lossless audio file compression.
b) The merits of using a computer as a digital audio transport.
Ultimately I do agree with you regarding the issue of CPU load on audio playback performance, but I think that this speaks more towards topic "b" than topic "a". For this reason, I do not see any fallacy in Greg's post. It's obvious that a computer can be a perfectly capable audio transport as long as you don't overburden it with concurrent tasks. Once this simple rule is heeded, issue "b" shouldn't be a worry. However, the validity of issue "b" does not presuppose the existence of issue "a".
"There are reports here of people that indeed did A/B tests with lossless compressed vs. uncompressed with all other variables the same. As always the people who don't believe there is a difference don't accept that the experiments are controlled enough and the ones that do believe there is a difference don't care about anyone else's experiments"
Your last point hits home. We could continue debating the point of whether lossless compression has audible artifacts, but I'm really not inclined to do that. In the end, I've said my part and I respect the rights of others to state their opposing opinions. It's only when matters are presented as fact that I think we should ask for a higher burden of proof to be presented.
here is a link to Apple support:
Yes, iTunes will rip only redbook, not SACD.Your best bet for highest quality and least space is Apple Lossless. (IIRC Stereophile's John Atkinson reported that Apple Lossless matched the sound of the original cd in his testing.)
However, I have found that for most iPod applications (in the car, exercising, on the plane, bus or subway) the format/sampling rate of the rip is not that significant because you won't be doing critical listening in an ideal environment. Better to use a more compressed format and cram more music onto that baby, unless you are planning to use it as the digital source in your main rig.
I ride the subway daily and agree that you don't NEED to use anything more than 128 or at most 256 for that. But, if you try to use your iPod as a source to a better system you will hear the difference.I use both lossless and compressed formats depending on the music. For me,loud garage band type stuff doesn't need the lossless format, but classical and acoustic jazz does. Experiment for yourself and see what works for you. Consider that a full CD is 700mb so that you'll get about 40-50 CDs worth or so onto a 30gb iPod with the lossless compression, maybe a bit more since it is still somewhat compressed.
MP3's sound pretty darn good these days actually. The encoder is constantly being revised and improved upon. Apple Lossless is your best bet though as they hold 100% of the information found in an uncompressed wav or aiff file, but in a more compact format. They call it lossless because it is an exact representation of the original data.
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