SonicStage 3.2: ATRAC3plus Frequency Analysis

[Ishiyoshi]

To complement the subjective listening tests done on the new bit rates of ATRAC3plus --> notably 320kbps (in this thread), I have conducted a frequency analysis for your technical curiosity.

*Thanks to greenmachine for the concise Adobe Audition guide.

Original file: Nina Simone's I Loves Porgy.

Green: original uncompressed file

Red: ATRAC3plus, 320kbps

Blue: ATRAC3plus, 256kbps

Yellow: ATRAC3plus, 192kbps

As greenmachine illustrated in his earlier frequency analysis, there are no significant difference between ATRAC3plus 320kbps and 256kbps. They are almost identical in terms of quality as shown in the graph above. However, one can easily discern ATRAC3plus, 192kbps from 320kbps and 256kbps. In addition, it is important to note that the frequency analysis is not the absolute answer to sound quality as there are other variables - notably artifacts

Discuss accordingly.

[sifun]

is there much of a quality difference between atrac 3 plus 256 and 192? frequency of atrac3pls 192 is quite off compared with the original, but how about we compare 192 mp3 and 192 atrac3plus?

[Ishiyoshi]

is there much of a quality difference between atrac 3 plus 256 and 192? frequency of atrac3pls 192 is quite off compared with the original, but how about we compare 192 mp3 and 192 atrac3plus?

←

Welcome to ALC!

Subjectively, ATRAC3plus 256kbps sounds fuller than ATRAC3plus 192kbps and it is technically better as you've already noticed - ATRAC3plus 192kbps have a much lower lowpass frequency than ATRAC3plus 256kbps. To elaborate, the instruments in the test track lacks clarity when compared to ATRAC3plus 256kbps and 320kbps. (For your information, the subjective listening test was done via PC with the MDR-SA3000 headphone)

However, it is important to note that the frequency analysis is not the absolute answer to sound quality as there are other variables - notably artifacts. A member from MDCF (greenmachine) conducted a similar test comparing ATRAC3plus 128kbps and ATRAC3 LP2. His result: "ATRAC3plus 128 kbps may have a lower lowpass frequency than LP2, but what you cannot see here is the awful artifacting of LP2."

In this case, ATRAC3plus 192kbps does not exhibit any discerning artifacts; however, there could be artifacts (after all, this is a lossy compression) but I just can't hear it. Greenmachine elaborates in the same post that this is because the lower lowpass frequency that ATRAC3+plus 192kbps has cannot be easily detected. It is almost impossible to discern the filter at 16kHz let alone 17kHz and 18kHz.

I would suggest you try converting the ATRAC3plus bit rates in question and judge the sound quality for yourself.

*I will try and post a frequency analysis of Mp3 192kbps and ATRAC3plus 192kbps shortly.

[Ishiyoshi]

As per requested: A frequency analysis between ATRAC3plus 192kbps and Mp3 192kbps CBR.

Original file: Nina Simone's I Loves Porgy.

Green: original uncompressed file

Red: ATRAC3plus, 192kbps

Blue: Mp3, 192kbps

Linear View

[sifun]

Wow very thorough! thanks for the analysis-

Yeah I shall try for myself when the official english release is about.

I'm worried about initialization and can't check in and back up my mp3s from my HD1-

[pata2001]

Note that with MP3, it's easy to re-configure your encoder (eg. lame) to do any lowpass of your preference. You can encode a 128kbps MP3 without any lowpass, or 320kbps with 16000Hz lowpass if you want to.

Ishiyoshi: It would be wonderful, and interesting, if you could do an analysis like this for the whole shebang of various Atrac bitrates.

[Ishiyoshi]

Ishiyoshi: It would be wonderful, and interesting, if you could do an analysis like this for the whole shebang of various Atrac bitrates.

←

I can do up to four bit rates per graph – will set up the remainder ATRAC3plus bit rates: 160kbps, 128kbps, 96kbps, 64kbps and 48kbps shortly.

[Ishiyoshi]

As per requested: A frequency analysis between ATRAC3plus 160kbps, 128kbps, 96kbps, 64kbps and 48kbps.

Original file: Nina Simone's I Loves Porgy.

Green: original uncompressed file

Red: ATRAC3plus, 160kbps

Blue: ATRAC3plus, 128kbps

Linear View

Original file: Nina Simone's I Loves Porgy.

Green: original uncompressed file

Red: ATRAC3plus, 96kbps

Blue: ATRAC3plus, 64kbps

Yellow: ATRAC3plus, 48kbps

Linear View

[pata2001]

Thanks a lot ishi. This is great, since Sony is never upfront with these kind of things (eg. frequency cutoffs).

As for those who are curious in cutoffs for Lame MP3 for the VBR presets, check this thread at hydrogenaudio: http://www.hydrogenaudio.org/forums/index....showtopic=18091

Note, you can always override those settings with Lame.

[sifun]

so now that we have a wider variety of bitrates,

Do you think atrac3plus sounds better than AAC?

[Leon]

Woah! Thanks for the charts Ishi

The 48 and 64 results appear similar to the AV Watch test results when A3+ debuted in early 2003 (for the NW-MS70D).

I read an opinion somewhere that the high-frequency "kinks" is something the iTunes MP3 encoder produces but many other MP3 codecs don't, and it might've contributed to some people perceiving iTunes MP3 to be lower quality.

I'll have to do more listening (and wipe out my HD5 first) before I form an opinion on the new A3+ bitrates.

sifun,

Traditionally ATRAC has always appeared brighter, more "edgy" to my ears than MP3 or AAC, no matter what bitrate or generation. My opinion is that ATRAC/3/plus have never focused on accurately reproducing the original, but instead on making attractive reconstructions. Given the sharp tendency of the ATRAC sound, the ability to reproduce the heft/body of the CD original is limited (until the 320 became available, at least). If I have to ABX the different codecs at high bitrate, I'm not sure I can tell MP3 or AAC apart from the original, but A3+ I just might be able to.

As for what each codec can perform at a given bitrate, I think AAC and A3+ are probably on par. There might be more to AAC but Apple hasn't paid much attention at all in that direction. A long time ago I saw a mention on hydrogenaudio that someday 128 AAC might be transparent... a boy can dream.

[atrain]

Traditionally ATRAC has always appeared brighter, more "edgy" to my ears than MP3 or AAC, no matter what bitrate or generation. My opinion is that ATRAC/3/plus have never focused on accurately reproducing the original, but instead on making attractive  reconstructions. Given the sharp tendency of the ATRAC sound, the ability to reproduce the heft/body of the CD original is limited (until the 320 became available, at least). If I have to ABX the different codecs at high bitrate, I'm not sure I can tell MP3 or AAC apart from the original, but A3+ I just might be able to.

←

fits in with bangraman's concern that the hd5 was only voted best sounding mp3 player due to sounding good rather than accurate.

http://phonephile.blogspot.com/2005/06/hd5s-got-secret.html

[bangraman]

Actually, no.

The HD5 is noticeably 'smoother' and also noticeably deficient in technical ability whichever codec you use, and this is prety apparent when compared alongside the Karma, iPod and JB3. In terms of the geek figures, it also measures relatively speaking a lot worse than the aforementioned players. The difference is much harder to detect by ear between the iRiver/iAudio and the HD5 especially with the iRiver, but at the psychological level the HD5 was once again 'nicer' yet 'not as good'.

And going back to the geek figures, all in all I was very surprised that the Sony came out bottom in all measurements in headphone and line out modes.

Oh yes, hello

Edited July 28, 2005 by bangraman

[atrain]

honestly, once again you went over my head. i'll reread your original post again & work out where i'm missing the point.

bangraman, have you spent anytime lstening to ATRAc3+ at 320kbs?

[auvi_joe]

Luke.......

Learn to trust your ears......

You don't need others to tell you what should sound good to you......

or something along those lines is what I heard in some blockbuster movies

[Leon]

Those of you who speak Japanese are probably aware of this going around the web: that the new Sony players play "faster", they will finish a 4-5 minute song 2-3 seconds before other players or ones on your computer.

atrain,

I think the key to understanding those statements is an assumption that there are morally right and wrong ways to engineer portable audio, and that pleasant does not mean things are done the "right" way

[atrain]

the diference between good & acurate never struck me as a moral one L.

[Leon]

I know what you mean

Just a thought... If I were to switch to A3+ for all my listening needs, I'm not sure what bitrate I'd default to. If you look at the battery life figures on paper, there's no huge difference between 64 and 256kbps - the gap is smaller than I'd expected for both Hi-MD and HDD. If that is true, then it probably makes sense to use all 256 or 320.

[atrain]

i'm currently at 75% atrac3+ 256 , 20% various high rate mp3s & the rest in 192 atrac3+ which is fine although is as obviously different to 256 as 256 is to 320 - the bitrates seem far more different than mp3s at similar gapped bitrates to me

****

i've decided to use spellcheck for awhile, my spelling is average at best. lucky i'm still paying attention or all this talk of nitrates might prove both confusing yet benificial to any suffering angina

[Leon]

Oh there's nothing wrong with your spelling yours truly here is one shining example that spotless spelling does nothing to advance oneself

That's a very interesting point... I'll probably wipe out my HD5 soon (for SS3.2) and I might go for 192 instead of 256 to free up some space for file storage.

[sifun]

Seems like there are some artifacts when converting mp3s to atrac3 plus? I tried converting a 256 mp3 to 192 a3+ and the sound quality was not good at all...

Anyone else get the same?

[Ishiyoshi]

Seems like there are some artifacts when converting mp3s to atrac3 plus? I tried converting a 256 mp3 to 192 a3+ and the sound quality was not good at all...

Anyone else get the same?

←

It is likely you will experience artifacts when converting from another lossy compression. Instead, you should convert from original uncompressed source.

[Christopher]

Try 256kbps mp3 to 256kbps ATRAC3plus and see if there is a difference - you should always try and keep mp3/ATRAC bitrates in comparable bitrate quality.

[sdass]

Maybe off topic here, if so, sorry. What do people think of A3+ at lower bit rates eg 64kbps? I have an NW-E407 and thus only 1GB to play with so I'm using 64kbps in order to squeeze more albums on, sound quality is fine but not great, am I being foolish here?

[Ishiyoshi]

Maybe off topic here, if so, sorry. What do people think of A3+ at lower bit rates eg 64kbps? I have an NW-E407 and thus only 1GB to play with so I'm using 64kbps in order to squeeze more albums on, sound quality is fine but not great, am I being foolish here?

←

Not at all - as long as it rocks your boat, it's not foolish. However, a majority of users may find the ideal bit rate being at either ATRAC3plus 192kbps or 256kbps.

[Garmstro]

I have indeed and I can't discern any significant difference between the two bit rates. If you are interested, I have done a frequency analysis for the new bit rates: click here.

←

Thanks, very interesting. When looking at the two graphs - in each graph there appear to be two sets of signals - is that correct? If so, what do the two sets represent?

Also, how do you explain in layman's terms the divergence at the high frequencies between say 192 and 256kbps. How would that present in terms of sound?

[Ishiyoshi]

Thanks, very interesting. When looking at the two graphs - in each graph there appear to be two sets of signals - is that correct? If so, what do the two sets represent?

←

The two graphs have essentially the same information - the first: a linear graph and the second: a logarithmic graph. If you review the linear graph, you can see four set of audio signal or audio file so to speak. One being the original uncompressed file and the other three being ATRAC3plus file – 320kbps, 256kbps and 192kbps. *see the graph’s legend and scroll down the first page of this thread for more analytical comparison between other ATRAC3plus bit rates

Also, how do you explain in layman's terms the divergence at the high frequencies between say 192 and 256kbps. How would that present in terms of sound?

←

Divergence at the higher frequencies between the bit rates shown in the graph represents how efficient the compression method replicates the original recording. As you can see, a lowpass filter at 18 kHz was used for the ATRAC3plus 192kbps and the ATRAC3plus 256kbps along with ATRAC3plus 320kbps is almost indistinguishable from the original. It is important to note that it is almost impossible to discern the filter at 16 kHz let alone 17 kHz and 18 kHz.

[Garmstro]

The two graphs have essentially the same information - the first: a linear graph and the second: a logarithmic graph. If you review the linear graph, you can see four set of audio signal or audio file so to speak. One being the original uncompressed file and the other three being ATRAC3plus file – 320kbps, 256kbps and 192kbps. *see the graph’s legend and scroll down the first page of this thread for more analytical comparison between other ATRAC3plus bit rates

Divergence at the higher frequencies between the bit rates shown in the graph represents how efficient the compression method replicates the original recording. As you can see, a lowpass filter at 18 kHz was used for the ATRAC3plus 192kbps and the ATRAC3plus 256kbps along with ATRAC3plus 320kbps is almost indistinguishable from the original. It is important to note that it is almost impossible to discern the filter at 16 kHz let alone 17 kHz and 18 kHz.

←

Thanks Ishiyoshi,

If we look at the linear graph, there appears to be two sets of four graphs (i.e., between 2,000 and 17,000 Hz there are two distinct lines, presumably where all 4 graphs coincide - and for lower and higher frequencies outside of this range the graphs diverge). What do the two sets of four graphs represent?

When you write "It is important to note that it is almost impossible to discern the filter at 16 kHz let alone 17 kHz and 18 kHz.", what do you mean? (I'm sorry I'm a complete beginner when it comes to this.) Do you mean the graphs shown are reflective of an 18khz filter, and would be different if a 16khz filter was used? How do the filters relate to human hearing?

Finally, where 192kbps diverges from the original in the low and high frequencies, does that mean bass and treble will be "fuzzy" sounding, or just different?

Thanks for all your help, Grant

[Ishiyoshi]

If we look at the linear graph, there appears to be two sets of four graphs (i.e., between 2,000 and 17,000 Hz there are two distinct lines, presumably where all 4 graphs coincide - and for lower and higher frequencies outside of this range the graphs diverge). What do the two sets of four graphs represent?

←

It’s the left and right channel.

Thanks Ishiyoshi,

When you write "It is important to note that it is almost impossible to discern the filter at 16 kHz let alone 17 kHz and 18 kHz.” what do you mean? (I'm sorry I'm a complete beginner when it comes to this.) Do you mean the graphs shown are reflective of an 18khz filter, and would be different if a 16khz filter was used? How do the filters relate to human hearing?

←

Just simply mean that our ears usually can’t hear frequency at that level mentioned above – unless you’ve bat or bionic ears. As for Low/High pass filters, I will use quotes from wikipedia to answer your query:

--> "The concept of a low-pass filter exists in many different forms, including electronic circuits (like a hiss filter used in audio), digital algorithms for smoothing sets of data, acoustic barriers, blurring of images, and so on. Low-pass filters play the same role in signal processing that moving averages do in some other fields, such as finance; both tools provide a smoother form of a signal which removes the short-term oscillations, leaving only the long-term trend."

--> "A high-pass filter passes 'high' frequencies fairly well, but attenuates 'low' frequencies. Therefore it is also called a low-cut filter or bass-cut filter. The term rumble filter is sometimes used. A high-pass filter is the opposite of a low-pass filter. See also bandpass filter. Hence it is useful as a filter to block any unwanted low frequency components of a complex signal whilst passing the higher frequencies. Of course, the meanings of 'low' and 'high' frequencies are relative, actually desired values would influence choice of component values in an implementation."

Finally, where 192kbps diverges from the original in the low and high frequencies, does that mean bass and treble will be "fuzzy" sounding, or just different?

←

It depends upon the type of headphone/earphone one employs. Basically, you will hear artifacts at this point – provided if you can pick it up. As I mentioned in my initial post, this is a subjective test, so it all depends.

[Garmstro]

It’s the left and right channel.

Just simply mean that our ears usually can’t hear frequency at that level mentioned above – unless you’ve bat or bionic ears. As for Low/High pass filters, I will use quotes from wikipedia to answer your query:

--> "The concept of a low-pass filter exists in many different forms, including electronic circuits (like a hiss filter used in audio), digital algorithms for smoothing sets of data, acoustic barriers, blurring of images, and so on. Low-pass filters play the same role in signal processing that moving averages do in some other fields, such as finance; both tools provide a smoother form of a signal which removes the short-term oscillations, leaving only the long-term trend."

--> "A high-pass filter passes 'high' frequencies fairly well, but attenuates 'low' frequencies. Therefore it is also called a low-cut filter or bass-cut filter. The term rumble filter is sometimes used. A high-pass filter is the opposite of a low-pass filter. See also bandpass filter. Hence it is useful as a filter to block any unwanted low frequency components of a complex signal whilst passing the higher frequencies. Of course, the meanings of 'low' and 'high' frequencies are relative, actually desired values would influence choice of component values in an implementation."

It depends upon the type of headphone/earphone one employs. Basically, you will hear artifacts at this point – provided if you can pick it up. As I mentioned in my initial post, this is a subjective test, so it all depends.

←

That's wonderful - thank you very much Ishiyoshi

[M4t]

Advice Please :

All of my music is LAME enc 192kbps VBR

I wish to keep that quality, what would you reccomend as settings for Atrac3+?

[Ishiyoshi]

Advice Please :

All of my music is LAME enc 192kbps VBR

I wish to keep that quality, what would you reccomend as settings for Atrac3+?

←

Welcome to ALC!

Since you have encoded your music in LAME 192kbps VBR, I would suggest that you keep the current settings unless you truly need gapless or your device does not support it. Personally, I prefer gapless playback at ATRAC3plus 256kbps; and obviously, use the original source if you ever need to encode to ATRAC3plus.

[NoOneHome]

Hi. It's good to find a decent forum on the new Atrac3plus bitrates

Hopefully you can help with some questions I have. I've got an MZ-RH10 at present (mostly 64k Atrac3plus music) but I'm looking to get an NW-A1000 or NW-3000. Having played with both in a shop, I prefer the 1000 (the 3000 seems quite large and heavy compared to the 1000 and NW-HDx players, and the 1000 screen appears sharper due to smaller pixels).

I know I could get roughly the same number of tracks I'm looking for on the NW-A1000 using A3+ 64k as I could on the NW-A3000 using MP3 192k, meaning the 1000 would offer the nicest unit (IMHO) and best size, but the 3000 would offer much better sound quality and a more flexible music file collection.

To make the 1000 more appealing, I was considering using one of the new A3+ bitrates for a good size/quality compromise. The question is what MP3 bitrates are the new A3+ 96k, 128k, 160k & 192k bitrates equivelent to, given that 64k A3+ is equivelent to 128k mp3, and which are worth considering?

Thanks

[simon.giesen]

Actually, no.

The HD5 is noticeably 'smoother' and also noticeably deficient in technical ability whichever codec you use, and this is prety apparent when compared alongside the Karma, iPod and JB3. In terms of the geek figures, it also measures relatively speaking a lot worse than the aforementioned players. The difference is much harder to detect by ear between the iRiver/iAudio and the HD5 especially with the iRiver, but at the psychological level the HD5 was once again 'nicer' yet 'not as good'.

And going back to the geek figures, all in all I was very surprised that the Sony came out bottom in all measurements in headphone and line out modes.

Oh yes, hello

Well, I do own a HD5 and I can confirm that this Walkman ist sounding "spectecular". Fuller, richer, nicer and stronger than all other players. If you could label this performance "accurate" depends on you.

What I noticed:

Using lower ATRAC bit rates blows the sound. Even using 256Kbit makes me feel this: slightly more bass "woom" and stronger than on the source material - even having all the EQs off. Recently I ripped my favourite CDs again by using ATRAC3Plus 352Kbit - wow: Now it sounds SPECTECULAR AND ACCURATE. Very transparent, somehow soft and tenderly, especially the higher tones but yet strong and deepest black in the bass. Try it... You won't achive this using any other codec or player. BUT: Please try it with high-quality phones.

Headphones I have used:

- Sony MDR V700 DJ

- Grado Reference Series RS-1

[CEBEP]

hello,

could anyone advise what is the memory consumption ratio im percentage compared to the same song ripped to mp3 and atrac3+ for192kbt and 256kbt. I heard that atrac3+ consumes twice as less space as the mp3 with same bitrate. if so, would it mean that the song encoded in atrac3+ format 256kb be similar in memory volume to the same one encoded in mp3 192kb? thanks

[Arkan]

I have a question. If I have song that plays in mp3-format 192kbps, should I then convert that to 192kbps in Atrac3+ or should I convert it to higher (I mean like 320kbps)???

Thank You for your answer!

[Guest Stuge]

I have a question. If I have song that plays in mp3-format 192kbps, should I then convert that to 192kbps in Atrac3+ or should I convert it to higher (I mean like 320kbps)???

Thank You for your answer!

Hey,Converting your mp3 to higer bitrate will not result in better sound quality..It`s better to Convert you mp3 file to Atrac3 plus 192kpbs.

But may i know why you want to convert your mp3 file .If you need gapless playback then convert to Atrac otherwise not .

[NoOneHome]

A few pointers that may help:

- If your player supports mp3s directly, don't transcode them (converting from one lossy format, eg. mp3, to another lossy format, eg. atrac3plus, should be avoided if possible as it can effect the quality and occasionally introduce sound glitches).

- Atrac3plus is far superior (no comparison) to mp3 at lower bitrates (<=160k), once you get to higher biterates (=>256k) it's much more difficult to tell the difference. If like me you have a fair number gapless CDs (no silences between tracks), then atrac3/atrac3plus should always be your first choice.

- I would always choose actrac3plus 128k (16x sampling) over the older atrac3 132k (4x sampling) for quality although some people prefer or are limited to the older atrac3 132k format.

- There's not much difference is size between formats at the same bitrate.

Hope this helps