[MacacoDoSom]

  I've noticed some clipping, mostly on a few mp3s somehow. not knowing what it was, at first I just checked the "avoid clipping"  in foobar, but that didn't seem to solve the problem which led me to think it was maybe on the DAC side. trying 2 DACs didn't felt kind of different but didn't solve the problem(maybe different upsampling, one having async USB? or whatever, IDK). I still had some minor clipping on a few tracks that shouldn't be there. my solution testing stuff randomly was to put -3db in foobar's preamp ^_^. I tried different values and settled for 3db somehow, guess I got lucky on that one(well -1db still audibly clipped sometimes, -2 felt ok so I played it safe and used -3). and that did the trick, so for a long time I didn't look further into it, using the family telling, "if it works don't screw*ing touch it!".
 
and it's the cool guy from JDS lab and some benchmark post on their website that made me realize what it was likely to be maybe 6months ago.
if you want, you can buy the DAC2, and apparently not worry about that anymore.  I find that paying 3db of noise floor is cheaper, but it does look like a pretty cool DAC.

 
When you compress to MP3 having intersampling peaks above 0dBFS, its irremediable clipping...sometime you'll notice it a lot, sometimes you don't notice it at all...

What I do before compressing to MP3 is a bit strange (some work). I rip the CD with EAC to flac, pass repalygain in foobar (it gives you -18dB loudness) if the replaygain is negative its OK, apply it and then convert to MP3 applying replaygain, if positive I wont touch it...
 
Sometimes I get -6 to -8 dB headroom, sometimes much less,
Never noticed any noise floor and at least the vol button is always in same position...
 
What I feel about this, is that most people is not aware of this problem and its the reason that most people say that MP3 sucks...
 
Do the guys that sell MP3 do something about this? I never bought any MP3 files, so I don't know, as I don't know nothing about iTunes and their AAC files...

 

[castleofargh]

  When you compress to MP3 having intersampling peaks above 0dBFS, its irremediable clipping...sometime you'll notice it a lot, sometimes you don't notice it at all...

What I do before compressing to MP3 is a bit strange (some work). I rip the CD with EAC to flac, pass repalygain in foobar (it gives you -18dB loudness) if the replaygain is negative its OK, apply it and then convert to MP3 applying replaygain, if positive I wont touch it...
 
Sometimes I get -6 to -8 dB headroom, sometimes much less,
Never noticed any noise floor and at least the vol button is always in same position...
 
What I feel about this, is that most people is not aware of this problem and its the reason that most people say that MP3 sucks...
 
Do the guys that sell MP3 do something about this? I never bought any MP3 files, so I don't know, as I don't know nothing about iTunes and their AAC files...

so you're saying that I'm not at all talking about the right stuff? could very much be TBH, as I had a symptom and came up with a the first why afterward that seemed like it could fit. like a pure audiophile ^_^.
I'll try going back to zero and play some mp3s for a few days to find a track that does the clipping, that's not the hard part, the hard part is getting one that shouldn't clip and wasn't clipping already on the CD. but at the time I noticed my stuff, going to -3db gain did solve my problem, and all I was using was an EQ where I also had a gain to keep everything below zero as not to clip like an idiot. so I didn't think it could be too much gain from some DSP or whatever.
 
 
 I don't really get "When you compress to MP3 having intersampling peaks above 0dBFS, its irremediable clipping..."
 I already have a hard time with those stuff when thinking basic PCM doing nothing more than being read. it's a problem with what is recorded onto the mp3, or a problem resulting from decoding it back to pcm?

 

[MacacoDoSom]

 

  When you compress to MP3 having intersampling peaks above 0dBFS, its irremediable clipping...sometime you'll notice it a lot, sometimes you don't notice it at all...

What I do before compressing to MP3 is a bit strange (some work). I rip the CD with EAC to flac, pass repalygain in foobar (it gives you -18dB loudness) if the replaygain is negative its OK, apply it and then convert to MP3 applying replaygain, if positive I wont touch it...
 
Sometimes I get -6 to -8 dB headroom, sometimes much less,
Never noticed any noise floor and at least the vol button is always in same position...
 
What I feel about this, is that most people is not aware of this problem and its the reason that most people say that MP3 sucks...
 
Do the guys that sell MP3 do something about this? I never bought any MP3 files, so I don't know, as I don't know nothing about iTunes and their AAC files...

so you're saying that I'm not at all talking about the right stuff? could very much be TBH, as I had a symptom and came up with a the first why afterward that seemed like it could fit. like a pure audiophile ^_^.
I'll try going back to zero and play some mp3s for a few days to find a track that does the clipping, that's not the hard part, the hard part is getting one that shouldn't clip and wasn't clipping already on the CD. but at the time I noticed my stuff, going to -3db gain did solve my problem, and all I was using was an EQ where I also had a gain to keep everything below zero as not to clip like an idiot. so I didn't think it could be too much gain from some DSP or whatever.
 
 
 I don't really get "When you compress to MP3 having intersampling peaks above 0dBFS, its irremediable clipping..."
 I already have a hard time with those stuff when thinking basic PCM doing nothing more than being read. it's a problem with what is recorded onto the mp3, or a problem resulting from decoding it back to pcm?

irremediable clipping...maybe not...
 
intersample peaks are peaks that don't exist in the PCM file, so the file is not clipping, they are in the reconstructed analogue audio, usually the DACs have enough headroom (in one of my DACs it goes to +14dBs) so there is no clipping, you get the problem when the DAC/CD player doesn't have enough headroom (I've heard of some) and when you do a lossy compression because the codecs don't like it much and distort... (I don't know much about lossy compression algorithms , but it's a know fact)
You can see this when upsampling, some SRCs have an option to prevent clipping, the intersample peaks become visible in the waveform also, what the software does to detect intersample peaks (true peaks or TP) is oversampling...

 

[stv014]

With the lossy codecs, it is not just inter-sample clipping, but clipping can occur already on the PCM stream as some samples could exceed 0 dBFS.

 

[MacacoDoSom]

  With the lossy codecs, it is not just inter-sample clipping, but clipping can occur already on the PCM stream as some samples could exceed 0 dBFS.

in the digital domain the samples cannot exceed 0dB full scale!!!! there is no space for it... only in 32 bit floating point...

 

[stv014]

  in the digital domain the samples cannot exceed 0dB full scale!!!! there is no space for it... only in 32 bit floating point...

 
In other words, they can. Of course, converting the output to an integer format limits it to 0 dBFS, but that is already clipping of the actual sample values.

 

[MacacoDoSom]

 

  in the digital domain the samples cannot exceed 0dB full scale!!!! there is no space for it... only in 32 bit floating point...

 
In other words, they can. Of course, converting the output to an integer format limits it to 0 dBFS, but that is already clipping of the actual sample values.

only with sub amateur work... nobody does a commercial (or amateur/home/bedroom) recording clipping in the digital domain... (does he/she?

)

 

[stv014]

I was originally referring to the clipping that possibly occurs when decoding lossy compressed audio.
 
Nevertheless, clipping is not uncommon in commercial music either, because of the loudness war.

 

[Roly1650]

I was originally referring to the clipping that possibly occurs when decoding lossy compressed audio.

Nevertheless, clipping is not uncommon in commercial music either, because of the loudness war.

Very true, one of the biggest selling albums of the last few years is clipped all to hell, every track, take no prisoners. This dazzling display of incompetence won just about all the major industry awards along the way. A sad reflection on the state of the recording industry and a public that accepts such crud. Shame is that imo the music was deserving of better treatment, but what do I know.

 

[MacacoDoSom]

 

I was originally referring to the clipping that possibly occurs when decoding lossy compressed audio.

Nevertheless, clipping is not uncommon in commercial music either, because of the loudness war.

Very true, one of the biggest selling albums of the last few years is clipped all to hell, every track, take no prisoners. This dazzling display of incompetence won just about all the major industry awards along the way. A sad reflection on the state of the recording industry and a public that accepts such crud. Shame is that imo the music was deserving of better treatment, but what do I know.

It seems there is a wrong understanding here about clipping, when the the waveform clips there is digital noise, the example I gave previously (the ZZ Top album) is not clipping...(in the digital domain at least)
 
people usually uses a brickwall compressor so it wouldn't clip
 
there is an exaggerated example with the files matched to a loudness of -18dB
 
https://www.dropbox.com/s/dwktz6j101y86yi/Frag_Ori.wav?dl=0 original file (headroom of -2dB)
 
https://www.dropbox.com/s/bdoc9oymv3iso55/Frag%2B12Cliped.wav?dl=0 clipped file +12dB (headroom of -10dB)
 
https://www.dropbox.com/s/ibjvqfdo2hjlles/Frag%2B12Compressed.wav?dl=0 compressed file +12dB (headroom of -7.9dB)
 
with the compressed file you can push it to 0dB FS without clipping and it will sound 7.9 dB louder than the original, that's what people do in the 'LOUDNESS WARS'

 

[Roly1650]

It seems there is a wrong understanding here about clipping, when the the waveform clips there is digital noise, the example I gave previously (the ZZ Top album) is not clipping...(in the digital domain at least)

people usually uses a brickwall compressor so it wouldn't clip

there is an exaggerated example with the files matched to a loudness of -18dB

https://www.dropbox.com/s/dwktz6j101y86yi/Frag_Ori.wav?dl=0 original file (headroom of -2dB)

https://www.dropbox.com/s/bdoc9oymv3iso55/Frag%2B12Cliped.wav?dl=0 clipped file +12dB (headroom of -10dB)

https://www.dropbox.com/s/ibjvqfdo2hjlles/Frag%2B12Compressed.wav?dl=0 compressed file +12dB (headroom of -7.9dB)

with the compressed file you can push it to 0dB FS without clipping and it will sound 7.9 dB louder than the original, that's what people do in the 'LOUDNESS WARS'

When I say clipped, that's by looking at the files in Audacity, which highlights clipping. Is Audacity wrong? It may well be.

 

[MacacoDoSom]

 

It seems there is a wrong understanding here about clipping, when the the waveform clips there is digital noise, the example I gave previously (the ZZ Top album) is not clipping...(in the digital domain at least)

people usually uses a brickwall compressor so it wouldn't clip

there is an exaggerated example with the files matched to a loudness of -18dB

https://www.dropbox.com/s/dwktz6j101y86yi/Frag_Ori.wav?dl=0 original file (headroom of -2dB)

https://www.dropbox.com/s/bdoc9oymv3iso55/Frag%2B12Cliped.wav?dl=0 clipped file +12dB (headroom of -10dB)

https://www.dropbox.com/s/ibjvqfdo2hjlles/Frag%2B12Compressed.wav?dl=0 compressed file +12dB (headroom of -7.9dB)

with the compressed file you can push it to 0dB FS without clipping and it will sound 7.9 dB louder than the original, that's what people do in the 'LOUDNESS WARS'

When I say clipped, that's by looking at the files in Audacity, which highlights clipping. Is Audacity wrong? It may well be.

Audacity is an extremely good program for it's price... it shouldn't be wrong, what files are you referring to? it would say it is clipping if the samples are hitting 0db because it doesn't have anyway of knowing if there was any actual clipping or not... when recording you shouldn't have any 0dB samples, if in your recording the maximum sample value is, let's say -3dB, then you can add a gain of +3dB without clipping and make your CD...and it will sound fine... what is usually done is to put some headroom of -0.2 to -0.5dB on the brickwall limiter/compressor, just to be safe, but this doesn't prevent those intersample peaks I was talking about... you will need a software that can actually detect them, Audacity doesn't do this by itself... (as far as I know)

 

[jdriver]

Inter-sample clipping is a HUGE problem.
 
Apple gives away software that lets you demonstrate this for yourself. It's called AU Lab and includes an AU AAC RoundTrip plugin you can use with any DAW that can use AU plugins and it is all free.
 
https://www.apple.com/itunes/mastered-for-itunes/
 
This is a fantastic tool and I urge anyone with an interest in this topic to download it and investigate for themselves.
 
Here's a video of the tool in action. The recording engineer for this particular recording was pretty shocked that I, as a consumer, would send him a scathing email regarding his handling of one of my favorite artists.
 
https://www.youtube.com/watch?v=6tb24lt09vU

 

[stv014]

 
it would say it is clipping if the samples are hitting 0db because it doesn't have anyway of knowing if there was any actual clipping or not...

 
It is likely to be clipping if runs of multiple samples are at 0 dBFS, and I think Audacity has an option for detecting this. Also, if a histogram of the sample values peaks at 0 dBFS, then it suggests clipping as well (as it can be seen on the 2008 version of this track). Without any dynamic compression or clipping the histogram would look approximately like a bell curve.
 
By the way, even when it is technically not "clipping", extreme brickwall compression can still produce audible intermodulation distortion.
 

you will need a software that can actually detect them, Audacity doesn't do this by itself... (as far as I know)

 
It is possible to detect inter-sample peaks by upsampling the track to a high sample rate (like 192 kHz), and then analyzing it. Obviously, clipping from the conversion itself should be avoided, either by using floating point samples and software that does not clip them, or by attenuating the track first.

 

[castleofargh]

I remember reading something about some record people pushing the bass well passed clipping to go to 11 in the loudness war. and that came from some tests showing that our brain was able to mentally add the expected but missing part of a slow sine wave. it worked really for low freqs and of course up to a point. but under those conditions, people wouldn't hear a clipping, just the sound as if the bass was really louder.
 
but that has nothing to do with intersample clipping. ^_^