Topic: Ape Vs MP3, no Difference ? (Read 44704 times)

enigman · « **Reply #50 on:** April 28, 2004, 08:29:03 am »

I seriously doubt that other factors such as "more conversion" or "increased current draw" could have an impact on whether an APE file sounds different from a WAV file. If you're using an external DAC, the bits coming from your computer (via SPdif or whatever) should be identical to those coming from a WAV. If you don't believe it, simply feed that digital stream into some sort of digital recording device (or back into your computer) and then do a bit for bit comparison of the resulting file. They will be identical, and if they're not, you probably have a problem somewhere else in your computer setup.

As far as your external DAC being effected by the increased CPU consumption of your computer, I find this highly unlikely, but of course not completely out of the realm of possiblity (we all know what an impact a butterfly flapping its wings can do). That said, if your system is so sensitive that your DAC is going to be noticeably effected by the increased current draw or EMI output of a totally separate device, then I would say you have bigger issues with your overall setup. I don't think you'd simply be noticing a difference between APEs and WAVs, you'd probably also end up having problems whenever someone opens the fridge in the other room or your neighboor fires up her WiFi connection.

I've been doing a fair amount of reading on ABX tests, and would strongly suggest anyone who feels that APEs are still inferior to WAVs do a double blind test with at least 16 rounds and post their results here. I'd be astonished if anyone could pick out a difference.

--Tim

Rizlaw · « **Reply #51 on:** April 28, 2004, 08:54:16 am »

Quote from: MarSies on April 27, 2004, 07:37:55 pm

How many people say that a digital system is better then the old analog way. Yes theoretically that's true. In real life a good record player and record beats a normal CD by far. Loads are CD's are recorded from analog tapes or just from records. Not always with old music.

MarSies .....

MarSies,

Perhaps your question should be in a separate thread. No doubt it will lead to a whole new debate in this forum on the merits (or lack thereof) of digital vs analog.

You only need to read publications like "The Absolute Sound" and "Stereophile" (mostly in years past) to appreciate how vociferous the debate was and, in some circles, continues to be. There were, and continue to be, compelling arguments on both sides.

These days, I don't think that anyone knowledgeable on the subject would disagree with the fact that 16 bit 44.1k CD audio was and is far from perfect, Nyquist Theorem and all. It simply didn't have enough bits and the sampling frequency was not high enough to capture the analog signal faithfully. There were and continue to be many reasons why most CD's didn't, and still don't, sound as good as a good LP played back on decent equipment. But this is changing. I have to say, that some of today's very best CD's do sound awfully good on a reasonably good digital playback system. I certainly don't think anyone misses the hiss, pops and ticks that most LP's had from the day the were purchased - or soon thereafter developed.

But my vote, at the moment, still goes to analog. Notice, I said, "at the moment", because now that I have purchased and listened to several DVD-A and SACD discs (mostly classical, soundtracks and a few pop vocals), I am beginning to think that well recorded high definition digital (24/96 or 24/292) can be "perceptually" about as good as the very best analog.

In the end, regardless of the musical delivery medium (analog or digital), it's what we hear that counts.

zevele10 · « **Reply #52 on:** April 28, 2004, 01:11:29 pm »

But my vote, at the moment, still goes to analog. Notice, I said, "at the moment", because now that I have purchased and listened to several DVD-A and SACD discs (mostly classical, soundtracks and a few pop vocals), I am beginning to think that well recorded high definition digital (24/96 or 24/292) can be "perceptually" about as good as the very best analog.
-=-=-=-=-=-=-=
You played them on the proper player?==A SACD player.
Or just on a regular player?

Rizlaw · « **Reply #53 on:** April 28, 2004, 02:14:12 pm »

Quote from: zevele on April 28, 2004, 01:11:29 pm

But my vote, at the moment, still goes to analog. Notice, I said, "at the moment", because now that I have purchased and listened to several DVD-A and SACD discs (mostly classical, soundtracks and a few pop vocals), I am beginning to think that well recorded high definition digital (24/96 or 24/292) can be "perceptually" about as good as the very best analog.
-=-=-=-=-=-=-=
You played them on the proper player?==A SACD player.
Or just on a regular player?

Yes, Zevele, on a Sony "No Boloney" (or is it bologna or baloney?) tried and true SACD player that I own and then again on a ridiculously expensive reference SACD player at my friend's high end audio store.

DougHamm · « **Reply #54 on:** April 28, 2004, 02:23:58 pm »

Quote

But my vote, at the moment, still goes to analog. Notice, I said, "at the moment", because now that I have purchased and listened to several DVD-A and SACD discs (mostly classical, soundtracks and a few pop vocals), I am beginning to think that well recorded high definition digital (24/96 or 24/292) can be "perceptually" about as good as the very best analog.

All my CDs are ripped to my media PC (the couchputer as I call it), but I have a Pioneer DV563A dedicated for DVD-Video, DVD-Audio, DTS-CD and SACD playback. I continue to be blown away by a number of the new DVD-Audio releases (Queen's Night At The Opera and Yes' Fragile and Magnification are two that stand out in my collection), and SACD as well (Dark Side Of The Moon is amazing). They're good enough that I would happily pick my ass up off the couch to change discs as required.

I certainly hope DVD-Audio in particular continues to gain market share. The latest advancement to the feature specification is the inclusion of AAC audio tracks right on the disc - though I do not know what sort of quality controls there may be, or DRM restrictions. Hopefully it'll be open enough to allow one to burn them to CD for playback in the car, one of the downsides to the format as it is today. What with road noise and all, anything with quality above that of a 192kbps MP3 is typically good enough for me while driving.

-Doug

loraan · « **Reply #55 on:** April 28, 2004, 02:38:42 pm »

Quote from: Rizlaw on April 26, 2004, 12:55:53 pm

I think any "conversion process" that changes the original WAV/CDA file, whether it's lossless or not, introduces some artifacts. These artifacts can be additive or substractive and they can be heard by critical ears even though test equipment sometimes can't easily demonstrate the reason critical ears hear a difference. This is the difference between the "Subjective" school of audio listening analysis and the "Measurements Are Everything" school of audio listening analysis which says if you can't measure it, you can't possibly be hearing it.

I have a few responses:

1. APE is bit-perfect to the original WAV. There is literally ZERO difference between playing an APE file and a WAV file in terms of the bits that are fed to Windows sound output devices. That's assuming, of course, that you encoded the APE with no processing--e.g. normalization--enabled. I agree that those who think they can hear a difference between an APE and the original WAV have a "golden ear", where I use "golden ear" in the sense of "a person who imagines that he can hear minute differences between speakers, codecs, etc... when really there probably isn't any difference."

Quote from: Rizlaw on April 26, 2004, 12:55:53 pm

One only has to read about the ongoing DVD-A (multibit) vs SACD (1-bit ultra high sampling) debate. Both formats are far higher definition audio systems than CD (certainly MP3, OGG, AAC, WMV, etc.) and yet High End Audio Journals seem to prefer the sound of SACD, claiming it sounds more analog, hence, real than DVD-A.

You can prefer whatever you like (welcome to America!). I challenge any of these guys to tell the difference between the same track encoded in DVD-A, SACD, and 44.1 redbook CD in a double-blind test. I bet a surprising percentage of them couldn't do it. And those who can? Their opinions I'll respect when they say SACD sounds "more analog".

PS: what the heck does "more analog" mean anyway?

loraan · « **Reply #56 on:** April 28, 2004, 02:42:41 pm »

Quote from: MarSies on April 26, 2004, 04:50:17 pm

I can imagine that there is an difference audible difference with wav or ape files. I recall using some stuff to clean CD's from the audio(phile) company were I bought my audioset. We had 2 identical (and original) CD's. We used the cleaning stuff on CD1 and not on CD2. CD1 was significantly different, and better, after cleaning.

In a double-blind test? Or even single-blind? Pardon my skepticism, but there is so much hooey surrounding audio and video processing that it brings my inner skeptic out.

Quote from: MarSies on April 26, 2004, 04:50:17 pm

Everyone can hear the difference. Just like with a record player and a CD player. I remember tests that i did with hearing the difference between both. Most people preferred the record player. CD's sounded to mechanical and digital.

I believe that there's a difference, but I don't understand what people mean by "more mechanical and digital". Do you mean a lower noise floor? A lack of high-frequency rolloff caused by the needle wearing out the record? What?

loraan · « **Reply #57 on:** April 28, 2004, 02:58:05 pm »

Quote from: Alex B on April 27, 2004, 11:01:00 am

http://doc.hydrogenaudio.org/wikis/hydrogenaudio/ABX ,

Personally prefer winabx (google it) to abx for the better interface.

paulr · « **Reply #58 on:** April 28, 2004, 03:02:01 pm »

There's a lot of 'audio snake oil' out there. One only has to read Stereophile for a few issues to see much of it.

Wooden pucks that you place around your listening room, green markers that you apply to the edge of your CDs, etc.

I do think that a good analog recording played on good equipment sounds better than redbook CD audio, simply because the waveform will be more accurate... But most people do not have the required equipment to actually *hear* the difference. Not to mention the fact that analog recordings (especially on vinyl) will degrade very quickly when played.

As far as the APE, WAV comparison... There is no issue here. Any differences heard are produced by either faulty equipment/software or by psychological processes.

loraan · « **Reply #59 on:** April 28, 2004, 03:03:21 pm »

Quote from: enigman on April 28, 2004, 08:29:03 am

I've been doing a fair amount of reading on ABX tests, and would strongly suggest anyone who feels that APEs are still inferior to WAVs do a double blind test with at least 16 rounds and post their results here. I'd be astonished if anyone could pick out a difference.

One problem with ABX'ing an APE is that the ABX apps I've seen only take WAV as an input. The assumption is that you will rip to WAV, encode to a lossy format, and then decode back to WAV. With APE, it's a given that the decode of the APE will be bit-perfect to the original WAV, and so ABX'ing will only test the validity of the ABX application (if it comes out 50/50, then the ABX app is correctly randomizing the test), not compare the codecs.

loraan · « **Reply #60 on:** April 28, 2004, 03:12:58 pm »

Quote from: paulr on April 28, 2004, 03:02:01 pm

I do think that a good analog recording played on good equipment sounds better than redbook CD audio, simply because the waveform will be more accurate... But most people do not have the required equipment to actually *hear* the difference. Not to mention the fact that analog recordings (especially on vinyl) will degrade very quickly when played.

I admit to being young enough to have never personally owned a record.

But I do understand Nyquist, which says that if sampling frequency > 2x maximum encoded frequency, then the original waveform can be reconstructed perfectly. Not approximately, but perfectly. That's why I don't understand when people say that an analog recording represents a truer waveform... Barring any flaws in the redbook format (such as the effective sampling rate or resolution being lower than the specified sampling rate or resolution) a CD should be capable of representing recordings with harmonics up to 22.5 Khz perfectly. Period.

This is a topic that I'm really interested in, and it's difficult to have a discussion without degrading to name-calling and semi-religious fervor. This forum has a pretty good record for having non-flame discussions, so I have high hopes

Bluey · « **Reply #61 on:** April 28, 2004, 03:15:23 pm »

Since I am mixing and creating my own music on the PC, I have questioned 24 bit 96k, but now I have some "analogue" VSTI's like the minimoog and MS20, and putting them up to 96k I can hear a difference where previously on others I could not. So I guess I'll be rendering up to this level for final mixes and some sort of delivery in dvd audio, which brings me to SACD....

I never knew about it until a few days ago. On closer examination of the technology I have never seen such crap spouted by the CD producers who issue SACD stickers on their disks. Most commerical CDs are mixed on protools ! So how the hell is that going to capture analogue feel ? Even recording electric guitars, and instruments its all mixed withing protools, not some SACD mastering system. So you will never have the full advantage of SACD. I know of no orchestral recordings that are direct from SACD either, only again derived from either a digital source or tape. I read the specs what I could find, something like 2Meg sampling ! I'm unsure what the frequency limitations of old tape is, but well you get the picture, SACD is just complete blurb because in most instanced DVD audio and SACD are derived from the same source.

Actually i'm looking for some sort of common free audio and delivery platform to stick 24 bit 96k and 5:1, compressed, so I'll look at OGG, but not many people have such specs on their PCs

.

Bluey.

paulr · « **Reply #62 on:** April 28, 2004, 03:22:34 pm »

Quote

I admit to being young enough to have never personally owned a record. But I do understand Nyquist, which says that if sampling frequency > 2x maximum encoded frequency, then the original waveform can be reconstructed perfectly. Not approximately, but perfectly. That's why I don't understand when people say that an analog recording represents a truer waveform... Barring any flaws in the redbook format (such as the effective sampling rate or resolution being lower than the specified sampling rate or resolution) a CD should be capable of representing recordings with harmonics up to 22.5 Khz perfectly. Period.

That's what the theory states. However, how many times have you seen a real world implementation achieve theoretical results? Almost never I think. Theory is necessary for development, but in practice, you almost never achieve those types of results. Not to mention that DACs vary greatly in quality from manufacturer to manufacturer.

In my opinion, to achieve a more 'analog' sound in practice, you need higher sample rates than Nyquist calls for.

zevele10 · « **Reply #63 on:** April 28, 2004, 04:05:59 pm »

Rizlaw

I asked cause i got the 16 Cds Roling Stones box set- They are SACD.

I did not have a player , but the work they did on the 'regular' cd part is amazing.

I'am a phono head , buying LPs to this day and many on 180 gr .

But i do not think i will use much the 2 180gr Lps i have when listening to the cd.

Zev Plays: David Crosby · Song With No Words (Tree With No Leaves) [6:00 · #7] From the album: If I Could Only Remember My Name [Monkey's Audio · 777 kbps]

pipsqueak · « **Reply #64 on:** April 28, 2004, 04:10:25 pm »

Quote from: paulr on April 28, 2004, 03:02:01 pm

There's a lot of 'audio snake oil' out there. One only has to read Stereophile for a few issues to see much of it.

Wooden pucks that you place around your listening room, green markers that you apply to the edge of your CDs, etc.

wooden pucks / green tags - great stuff!!!

not that i would ever use them but what are they 'supposed' to do?

wooden pucks = dampening?

green tags???

paulr · « **Reply #65 on:** April 28, 2004, 04:18:54 pm »

Quote

wooden pucks = dampening?

green tags???

The wooden pucks are supposed to dampen reflections... But it occurs to me that you don't need to spend a million dollars to do this. Expensive wooden pucks just give you that psychological effect that most of this 'snake oil' provides.

The green markers are supposed to "reflect scattered laser light" back into the CD and that will somehow improve the sound quality. We are apparently supposed to believe that if laser light is scattered and leaves the surface of the disc, via the edge, that it will somehow reduce the quality of the data that is read... My question is: once you reflect the light that is already traveling *parallel* to the disc back into the disc, how does it make the leap and travel up to the sensor? Magic?

It's complete hogwash, but people fervently defend this kind of stuff, sad as that is.

pipsqueak · « **Reply #66 on:** April 28, 2004, 04:24:41 pm »

wooden pucks - pah, i have piles of strategically placed clothes and old newspapers and last night chinese take-away scattered around the floor. each of these are made of soft material and work very well to dampen reflections and refrations thus improving my listening experience...

Listening to: 'Take On Me / A-Ha' from 'The Big 80s' by 'Various' on Media Center 10

[EDIT: just realised i have mis-spelt dampen with an N in the middle spelling a rude-ish word, and interact bleeps it as **pen - im so impressed, and obviously a bad speller!]

Sir Alan · « **Reply #67 on:** April 28, 2004, 04:33:18 pm »

Wooden pucks? Haven't heard of that one, but the green marker on CDs is one of my favourite «snake oil» stories. As I understand it, the theory is that running a green marker pen around the edge of a CD has a miraculous effect, somehow improving the quality of the sound reproduction. I suspect it was dreamed up by someone who had bought a job lot of green marker pens which he couldn't shift. Some people will believe anything.

I suppose that by sealing the edge it might prevent further deterioration of very old CDs of 1980s vintage (on some of these the metal layer extended to the outer edge of the disc where it was exposed to the air and gradually oxidised and degraded) but even my oldest CDs with visible edge rot still play perfectly after more than sixteen years.

[Listening to «Scherzo and Trio» on «Union Café» by the Penguin Café Orchestra]

DougHamm · « **Reply #68 on:** April 28, 2004, 04:35:20 pm »

Quote from: Bluey on April 28, 2004, 03:15:23 pm

I know of no orchestral recordings that are direct from SACD either, only again derived from either a digital source or tape. I read the specs what I could find, something like 2Meg sampling ! I'm unsure what the frequency limitations of old tape is, but well you get the picture, SACD is just complete blurb because in most instanced DVD audio and SACD are derived from the same source.
Bluey.

Here's an interesting forum read: http://www.hydrogenaudio.org/index.php?act=ST&f=1&t=3390.

Sony and Philips use DSD to archive masters of analogue recordings; in this situation the transfer directly to SACD would skip a lot of filtration and provide the closest semblance to the original analogue master (and identical to the DSD archive). It's no wonder that they're the biggest proponents of the technology.

As you point out, if the master is not DSD from analogue, and it's been converted to PCM at some point between the artist, the remastering process, and your ears (i.e.by some cheap SACD players in order to apply DSP), SACD's benefit over DVD-Audio is suspect.

However the flip side is that these recordings still generally sound really damned good compared to CD versions, because a lot of TLC goes into their remastering. Comparing stereo to stereo, if as much work went into the remastering of CD titles they'd probably sound really great too - but it would seem all the effort today is spent remastering for SACD and DVD-Audio, not CD.

-Doug

enigman · « **Reply #69 on:** April 28, 2004, 05:29:15 pm »

Quote from: loraan on April 28, 2004, 03:03:21 pm

Quote from: enigman on April 28, 2004, 08:29:03 am
I've been doing a fair amount of reading on ABX tests, and would strongly suggest anyone who feels that APEs are still inferior to WAVs do a double blind test with at least 16 rounds and post their results here. I'd be astonished if anyone could pick out a difference.

One problem with ABX'ing an APE is that the ABX apps I've seen only take WAV as an input. The assumption is that you will rip to WAV, encode to a lossy format, and then decode back to WAV. With APE, it's a given that the decode of the APE will be bit-perfect to the original WAV, and so ABX'ing will only test the validity of the ABX application (if it comes out 50/50, then the ABX app is correctly randomizing the test), not compare the codecs.

From what I've read, FooBar has both an APE plugin, as well as an ABX tool, so I would assume it could be used to compare WAV and APE (though I've never actually tried it). That said, I agree that it would be a pointless test, but if someone really feels there's a difference, they should keep quiet until they can positively ABX it.

--Tim

Rizlaw · « **Reply #70 on:** April 28, 2004, 06:33:03 pm »

Quote from: zevele on April 28, 2004, 04:05:59 pm

Rizlaw

I asked cause i got the 16 Cds Roling Stones box set- They are SACD.

I'am a phono head , buying LPs to this day and many on 180 gr .

But i do not think i will use much the 2 180gr Lps i have when listening to the cd.

Zev,

I understand. I continue to be a lover of the analog LP. I've been collecting LPs for over 40 years. Lately, however, my Goldmund Reference turntable sits, lonely, in the corner of my media room. From time to time, in moments of weakness, I think about selling it.

Well recorded and produced LPs, new and used, have become too expensive to continue "collecting". I think that digital audio has matured enough that I am now satisfied making the change to digital. I will continue to listen to my analog LP collection and appreciate it's many sonic virtues.

I'm sure, that when you purchase an SACD player you will find your Rolling Stones will sound even better. Might I recommend you check out a Sony DVP-NC685V or a Denon DVD-2200. The Denon's a universal format player (DVD, DVD-A and SACD), the Sony is not. They both have exceptional SACD performance.

Happy Listening.

fex · « **Reply #71 on:** April 28, 2004, 07:22:22 pm »

Quote from: paulr on April 28, 2004, 04:18:54 pm

...The green markers are supposed to "reflect scattered laser light" back into the CD and that will somehow improve the sound quality....

Some friends qualified me to be a little bit special about my requirements concerning music and quality. But what I read in this thread is to much for me.

Listening to: 'I Just Can't Help Believin' (Live)' from 'Forever In Love' by 'Elvis Presley' on Media Center 10

geekbeats2 · « **Reply #72 on:** April 29, 2004, 02:08:47 am »

In theory, there should not be any perceptible difference on 99+% of material to most people, somewhat lower for perceptive people.

Since APE is identical to the original wave, this question is really: can you hear the difference between LAME --alt-preset insane and the original .WAV, to do this would require a bit of artifact recognition training for ya ears. Now if youre spending your time attempting to identify miniscule artifacts embedded in silence well youre probably not going to be enjoying the music. Audiophiles generally are more concerned with how perfect their equipment can perform as opposed to simply appreciating a good melody and a good solid dose of music theory.

Alex B · « **Reply #73 on:** April 29, 2004, 06:23:43 am »

I revamped my earlier comment:

I can sometimes hear the APE/MP3 difference. One recent example was when I ripped a classical symphony and encoded both formats: APE and LAME --alt preset extreme. At first they sounded identical. After a while I started to notice subtle occasional differences: At those moments when the orchestra was playing loudly, quiet background sounds like concert hall echoes, sounds from some quiet instruments and noises generated by the audience were different or even missing in MP3. Those sounds were more natural in APE.

So the orchestra was playing the loud part of the symphony, but at the same time there were some quiet sounds and noises, which were only barely audible. In this kind of situation the lossy compression fails to sound accurate.

Those differences had nothing to do with the common artifacts: bad frequency responses, harmonic or IM distortions, hisses etc. Instead, some of the quiet sounds were totally missing or they sounded so different that it was difficult to recognize the instrument. All this had a slight effect on the feeling of presence.

Though I must point out that those differences were minor and it's was not easy to find them.

Sauzee · « **Reply #74 on:** April 29, 2004, 10:00:39 pm »

Quote

Audiophiles generally are more concerned with how perfect their equipment can perform as opposed to simply appreciating a good melody and a good solid dose of music theory.

I've often thought that if I worried a little less about the sound quality of the music, that I might enjoy it more - so you're point is a good one!

phatanhappy · « **Reply #75 on:** April 29, 2004, 10:52:05 pm »

Ahhh the magic. The hours I have put forth on this subject.
Here is the skinny, surprisingly - it has not been addressed.
In a computer - a disk is read 010101001 blah blah blah. if it comes to an error- it stops says HEY I HAVE AN ERROR - BAD FILE, it might mark the file bad, or if its between the files in the "other " area between files - it says - disk bad.
In comes Red book audio, wearing its oversampling hat, looking all snazzy. It says I will keep on --keeping on even when I see a bump. I will have enough data from surrounding bits to either skip or guess (depending on quality of drive /firmware) the information that was there. If we were talking about a spreadsheet / database you would have lost data - and the file would be unreadable - you might run a tool on it to "recover" the file which would be guessing what was cutout -or adding a EOF .....
SINCE we are talking about music, specifically a series group of 0 and 1 sampled at VERY specific rate who is to say missing a 1 or a 0 is audible when you are listening to 200,000 of them per minute- through a speaker (either ribbon or cone) that is vibrating/moving as fast as it can. If we start missing 100 bits - or a 1000 bits - eventually it becomes noticable, on cheep speakers - they dont move fast enough for you to hear the difference - so there is none. If you take a CD recorded at 1400bits per second - and re-encode it at 128 bits per second - you have HACKED a whole lot of data out, good speakers - mean bigger diffence, played thru the pc speaker = no difference.

I hope that simplifes the Data extracton piece in relation to audible notes.

More magic, black magic
Given a perfect world, perfect cd recording, perfect drive, perfect temperature - once the file is extracted - it will be perfect reproduced from file to file to file, till you write it to an imperfect medium, going down to a floppy, and or CDrom - introduced medium flaws back into the loop, depending on the mood of your drive - you could have different results on the actual recording (and hence play back) - if you want to test this, use a cheep cd rom drive, rip a wav or other high quality file to a cd, take a skrew driver and run it over a different factory cd several times and really mar the surface, put the disk in the drive and extract the cd using ultra secure mode - let it whail for 2 hours or so, stop the process, insert a new blank cd and immediatly re-record the high quality file. play back of both disks will show the stress on the burner causing imperfect writes to the disk, if you were to re-rip the disks and compare the files - you would see a difference in file size. Better CDrom drives - we have all heard of plextor - will handle the abuse better. I have burned out cheep drives doing data extraction, and tested the process over and over. This type of stress happens to all the audio equipment once it heats up - or its pusshed hard - the quality changes. again you get what you pay for.

Once you have a Wav or cda file - its a pure as it can get (from that cd/drive combination). These files can move over a network - from hd to HD with out loosing a beat, the medium is not tolerent of errors (it doesnt use the redbook standard) . Hence - you can zipit - unzip it, ape it - unape it , mp3 it - ......wait a minute - there is no - un mp3 - once you hack it its gone..... and do a binary compare of the files is EXACTLY the same. As far as diffences heard - on a PC - there could be lots of things causing the problem - not the file manipulation. Once we discover latiencey we see that cpu speed, process running, HD performance, sound card quality, codecs, DSP all effect the speed and timing of the play back ( and the audio standard of keep on - keeping on comes back) ape files, expecially ones using the highest compressions settings on a slower computer (less then 2ghz) with not enough ram (less then 128meg), running lots of process (virus scan sw, Instant messinger,...) does cause a quality performance issue, sometime is causes pauses or pops, sometimes is subtle - like it just dont sound right. I have notice this on more faster complex music, lots of instruments playing at once, and have played slower beat less complex music and not seen the problem.

Ok - so I am a novelist wanna be, I will leave further discussions of how SW handle music and "interperts" it for a later thread.

hope this helps

Phatanhappy
20years in computers, 4 working for a "golden ear" audio file

Bluey · « **Reply #76 on:** April 30, 2004, 06:43:26 am »

Quote from: phatanhappy on April 29, 2004, 10:52:05 pm

Ahhh the magic. The hours I have put forth on this subject.
Here is the skinny, surprisingly - it has not been addressed.
In a computer - a disk is read 010101001 blah blah blah. if it comes to an error- it stops says HEY I HAVE AN ERROR - BAD FILE, it might mark the file bad, or if its between the files in the "other " area between files - it says - disk bad.
In comes Red book audio, wearing its oversampling hat, looking all snazzy. It says I will keep on --keeping on even when I see a bump. I will have enough data from surrounding bits to either skip or guess (depending on quality of drive /firmware) the information that was there. If we were talking about a spreadsheet / database you would have lost data - and the file would be unreadable - you might run a tool on it to "recover" the file which would be guessing what was cutout -or adding a EOF .....
SINCE we are talking about music, specifically a series group of 0 and 1 sampled at VERY specific rate who is to say missing a 1 or a 0 is audible when you are listening to 200,000 of them per minute- through a speaker (either ribbon or cone) that is vibrating/moving as fast as it can. If we start missing 100 bits - or a 1000 bits - eventually it becomes noticable, on cheep speakers - they dont move fast enough for you to hear the difference - so there is none. If you take a CD recorded at 1400bits per second - and re-encode it at 128 bits per second - you have HACKED a whole lot of data out, good speakers - mean bigger diffence, played thru the pc speaker = no difference.

I hope that simplifes the Data extracton piece in relation to audible notes.

More magic, black magic
Given a perfect world, perfect cd recording, perfect drive, perfect temperature - once the file is extracted - it will be perfect reproduced from file to file to file, till you write it to an imperfect medium, going down to a floppy, and or CDrom - introduced medium flaws back into the loop, depending on the mood of your drive - you could have different results on the actual recording (and hence play back) - if you want to test this, use a cheep cd rom drive, rip a wav or other high quality file to a cd, take a skrew driver and run it over a different factory cd several times and really mar the surface, put the disk in the drive and extract the cd using ultra secure mode - let it whail for 2 hours or so, stop the process, insert a new blank cd and immediatly re-record the high quality file. play back of both disks will show the stress on the burner causing imperfect writes to the disk, if you were to re-rip the disks and compare the files - you would see a difference in file size. Better CDrom drives - we have all heard of plextor - will handle the abuse better. I have burned out cheep drives doing data extraction, and tested the process over and over. This type of stress happens to all the audio equipment once it heats up - or its pusshed hard - the quality changes. again you get what you pay for.

Once you have a Wav or cda file - its a pure as it can get (from that cd/drive combination). These files can move over a network - from hd to HD with out loosing a beat, the medium is not tolerent of errors (it doesnt use the redbook standard) . Hence - you can zipit - unzip it, ape it - unape it , mp3 it - ......wait a minute - there is no - un mp3 - once you hack it its gone..... and do a binary compare of the files is EXACTLY the same. As far as diffences heard - on a PC - there could be lots of things causing the problem - not the file manipulation. Once we discover latiencey we see that cpu speed, process running, HD performance, sound card quality, codecs, DSP all effect the speed and timing of the play back ( and the audio standard of keep on - keeping on comes back) ape files, expecially ones using the highest compressions settings on a slower computer (less then 2ghz) with not enough ram (less then 128meg), running lots of process (virus scan sw, Instant messinger,...) does cause a quality performance issue, sometime is causes pauses or pops, sometimes is subtle - like it just dont sound right. I have notice this on more faster complex music, lots of instruments playing at once, and have played slower beat less complex music and not seen the problem.

Ok - so I am a novelist wanna be, I will leave further discussions of how SW handle music and "interperts" it for a later thread.

hope this helps

Phatanhappy
20years in computers, 4 working for a "golden ear" audio file

Really not to insult anybody, but I think you should understand how PCs work internally and how compression works in detail before spouting such drivel and incorrect information. I never read before such stupidity coming from a none techie wannabe.

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Author Topic: Ape Vs MP3, no Difference ? (Read 44704 times)

zevele10

zevele10

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