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Why do I hear difference between FLAC and AIFF?

sangbro

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First of all, I’m not a voodoo person, perfectly understand that technically both must have the same quality.

Both are lose-less but FLAC is only compressed. So when I decide to rip my CDs, I first choose FLAC.

Currently, I only have B&W Formation Duo speakers at home - so I use Airplay. (iPhone 11max with app called FLACBOX.)

Just out of curiosity, I rip with other formats like Aiff too, to test it.


The result is a bit puzzling. I can almost instantly tell the difference. I feel like FLAC is not loseless but normal compressed files compared to AIFF.

I’m not talking about “oh I hear the difference after changing the cable” (Btw I assume that this might be imagination or the slight change of electric characteristic done by cable slight colors the sound.)

I’m talking about loss of spacial size / details (that usually not detectable with headphone but showing up with focused listening with loud speaker) that typically show the file has some loss. Some types of music not much, but some music it is more obvious than others.


My best guess is, even though FLAC is lose-less it’s compressed. So when I play a song in the iPhone, iPhone needs to de-compressed it.

Maybe iPhone is not fast enough, so this process creates some limitation? Versus aiff, iPhone can read the file just as it is.

Are there any other possible technical reasons behind this? Hmm. Or am I hallucinating? Anybody tries the same thing?

For my personal record, I recognize this difference when I play stan getz the girl from ipanema.
 

PaulD

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Did you do this listening test with controls, such as a blind AB or ABX test? "Sighted" testing is notoriously unreliable, as the evidence has shown.

When I first heard people claim this (difference between AIFF, WAV and FLAC) I tested this and found no difference, even to the point of unpacking the files into memory and doing a bitwise comparison - no difference. I listened blind and could not tell a difference between the files.
 
OP
S

sangbro

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Did you do this listening test with controls, such as a blind AB or ABX test? "Sighted" testing is notoriously unreliable, as the evidence has shown.

When I first heard people claim this (difference between AIFF, WAV and FLAC) I tested this and found no difference, even to the point of unpacking the files into memory and doing a bitwise comparison - no difference. I listened blind and could not tell a difference between the files.
Yes, in my living room. Due to my speaker restiction, (B&W Formation DUO does not have any other input options except wireless, in my case, Airplay2 only) I have listened to the music with Airplay2/Flacbox app for years with the exact same settings. I wish I can make scientific record of this somehow.

I’m not talking about “subtle” difference, or “I feel different” or “somehow sounds become more airy Or lively” subjective BS.

Especially, after I spent whole week to rip most of my CD collections as FLAC.

After done with my week long ripping, I sat down and listen to “the girl from ipanema” AIFF version that I had ripped before and FLAC version that I just ripped.

The difference is so obvious that I had to double check. Indeed, I rip from that CD again as AIFF and FLAC to make sure.
After couple tests - blind, inviting friends, asking my wife, asking kids, difference are shown.

I’m curious if there is any possibility that not every device, but certain devices have limitation on decompress Flac fully.
(B&W Duo limitation? Airplay limitation? iPhone limitation? App limitation?)

From what I understand technically, this should not happen. Very weird.
 

escksu

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Yes, in my living room. Due to my speaker restiction, (B&W Formation DUO does not have any other input options except wireless, in my case, Airplay2 only) I have listened to the music with Airplay2/Flacbox app for years with the exact same settings. I wish I can make scientific record of this somehow.

I’m not talking about “subtle” difference, or “I feel different” or “somehow sounds become more airy Or lively” subjective BS.

Especially, after I spent whole week to rip most of my CD collections as FLAC.

After done with my week long ripping, I sat down and listen to “the girl from ipanema” AIFF version that I had ripped before and FLAC version that I just ripped.

The difference is so obvious that I had to double check. Indeed, I rip from that CD again as AIFF and FLAC to make sure.
After couple tests - blind, inviting friends, asking my wife, asking kids, difference are shown.

I’m curious if there is any possibility that not every device, but certain devices have limitation on decompress Flac fully.
(B&W Duo limitation? Airplay limitation? iPhone limitation? App limitation?)

From what I understand technically, this should not happen. Very weird.

Just a friendly warning, you may get flamed for your post, esp. this part:

After couple tests - blind, inviting friends, asking my wife, asking kids, difference are shown.
 

scrubb

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Just a friendly warning, you may get flamed for your post, esp. this part:

After couple tests - blind, inviting friends, asking my wife, asking kids, difference are shown.

But I think OP is saying there’s a very obvious difference between the files. As a crass example; you certainly don’t need ABX testing to know there’s a difference between Laptop speakers and any floor standing speakers.

So, we know there shouldn’t technically be a difference, but there seems to be a difference. What could cause that? Recording settings, playback settings, faults or limitations in Equipment? I don’t have enough tech knowledge to answer this.
 

maxxevv

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Check the sampling rate differences between formats. My guess is, if you can hear differences, it may be down to that rather than inherent in the file format.

Some DAC's / OS drivers can behave differently when different sampling rates are used. Try again with both formats ripped using the same sampling rate if they are not the same.
 
OP
S

sangbro

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How about uploading 10 seconds of each file where you hear an obvious difference and let forum members examine the files?
I do not have any kind of professional recording device except my iPhone. So not sure that can do it right, but I will try.

I’m on business trip now, so once I get back I’ll give a shot.
 
OP
S

sangbro

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But I think OP is saying there’s a very obvious difference between the files. As a crass example; you certainly don’t need ABX testing to know there’s a difference between Laptop speakers and any floor standing speakers.

So, we know there shouldn’t technically be a difference, but there seems to be a difference. What could cause that? Recording settings, playback settings, faults or limitations in Equipment? I don’t have enough tech knowledge to answer this.

Technically there is no difference between FLAC and AIFF.

So my best guess is somehow there is something in the middle. (My mistake, Device limitation, Unknown error)

I do not think that the difference I feel even requires the lab test. When I just hear the first part, I was like “what the heck...”
 
OP
S

sangbro

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Check the sampling rate differences between formats. My guess is, if you can hear differences, it may be down to that rather than inherent in the file format.

Some DAC's / OS drivers can behave differently when different sampling rates are used. Try again with both formats ripped using the same sampling rate if they are not the same.
I will check the sampling rate. I’m not a tech savy person (or don’t really care the finest details that I usually can’t even hear.), so
I used XLD (popular among mac users to rip CD), and used the default (meaning I didn’t do anything) FLAC setting.

For AIFF, I used iTUNE CD ripping function (also default).

I’m on a business trip now, so once I get back, I will check if these programs’ default sampling rates are somehow differ.
Also, I think I better record 10 sec recording with my iPhone.
 

Chromatischism

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FLAC allows tagging, etc, so it would be ideal.

I agree that there is something about the way a device in your system is handling the files.
 

pma

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Make a Foobar ABX test between the same file in AIFF and flac. Otherwise the “ findings” make no sense. Also check you have no different resampling etc when playing flac x AIFF.
 

escksu

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But I think OP is saying there’s a very obvious difference between the files. As a crass example; you certainly don’t need ABX testing to know there’s a difference between Laptop speakers and any floor standing speakers.

So, we know there shouldn’t technically be a difference, but there seems to be a difference. What could cause that? Recording settings, playback settings, faults or limitations in Equipment? I don’t have enough tech knowledge to answer this.

Well, I would say it could be placebo effect, esp. since there is no evidence of any kind to support OP's claim.
 
OP
S

sangbro

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Make a Foobar ABX test between the same file in AIFF and flac. Otherwise the “ findings” make no sense. Also check you have no different resampling etc when playing flac x AIFF.
All I can do is making short iPhone video.
Also as I said, my guess is there might be something in the middle process.
 

waynel

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First of all, I’m not a voodoo person, perfectly understand that technically both must have the same quality.

Both are lose-less but FLAC is only compressed. So when I decide to rip my CDs, I first choose FLAC.

Currently, I only have B&W Formation Duo speakers at home - so I use Airplay. (iPhone 11max with app called FLACBOX.)

Just out of curiosity, I rip with other formats like Aiff too, to test it.


The result is a bit puzzling. I can almost instantly tell the difference. I feel like FLAC is not loseless but normal compressed files compared to AIFF.

I’m not talking about “oh I hear the difference after changing the cable” (Btw I assume that this might be imagination or the slight change of electric characteristic done by cable slight colors the sound.)

I’m talking about loss of spacial size / details (that usually not detectable with headphone but showing up with focused listening with loud speaker) that typically show the file has some loss. Some types of music not much, but some music it is more obvious than others.


My best guess is, even though FLAC is lose-less it’s compressed. So when I play a song in the iPhone, iPhone needs to de-compressed it.

Maybe iPhone is not fast enough, so this process creates some limitation? Versus aiff, iPhone can read the file just as it is.

Are there any other possible technical reasons behind this? Hmm. Or am I hallucinating? Anybody tries the same thing?

For my personal record, I recognize this difference when I play stan getz the girl from ipanema.
Probably placebo effect unless something is going grossly wrong in your system. The good news is that if your system is not handling FLAC properly, there is no need to re-rip your collection. dBPoweramp can batch convert your library from FLAC to Apple lossless.
 
OP
S

sangbro

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Well, I would say it could be placebo effect, esp. since there is no evidence of any kind to support OP's claim.
I think it is too much for placebo effect.
Honestly, I know what my experience sound like in general. I use default setting of xld / tune and also use default setting of flacbox app. (44.1 output sampling rate, I don’t even touch eq setting)

I just thought that there would be something in the middle process, and someone might know about it.
 

Χ Ξ Σ

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Since you use XLD, you can write/edit a .cue file using TextEdit and enter the following text. This should allow you to create a file containing the first 10 seconds of the song.

PERFORMER "AAAA"
TITLE "TITLE"
FILE "FILE.flac" WAVE

TRACK 01 AUDIO
PERFORMER "PERFORMER"
TITLE "1"
INDEX 01 00:00:00

TRACK 02 AUDIO
PERFORMER "PERFORMER"
TITLE "2"
INDEX 01 00:10:00
 
OP
S

sangbro

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Probably placebo effect unless something is going grossly wrong in your system. The good news is that if your system is not handling FLAC properly, there is no need to re-rip your collection. dBPoweramp can batch convert your library from FLAC to Apple lossless.
At this point I don’t know where the trouble is, and also technically it’s very simple and straight forward. Thanks for the software info.

When other people make this kind of thing I also didn’t even know where to start.
 
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