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TooLowToZero
Mar 11, 2013, 07:55 AM
Hi, I am sure this question must have been answered before, so please forgive me.

I have a new Nano 7 gen and have put selected playlists on it, as much as will fit on.
I have a pair of skullCandy headphones of medium quality,

If I reduce the bit rate down to 128 from iTunes 256, will there be a noticeable difference? I have tried 128 and cannot make my mind up if there is any difference!

I listen on the train with noise around me and was curious what you think and am I missing out on sound quality. Thanks



dXTC
Mar 11, 2013, 09:11 AM
The difference is a bit more noticeable in a quiet environment, and the compression in the 128-kbit versions tends to affect high-frequency sounds like hi-hats.

However, you may have answered your own question. If you can't really tell the difference in your usual listening environment, then sync at a lower bitrate.

If you believe you'll be in a quieter listening environment in the future and want a little bit better quality, but still like the extra space, then "take the middle of the road" and sync at the 192 bitrate. It's a nice compromise between the two; well over 95% of listeners have problems hearing the difference between 192 and 256 kbits.

TooLowToZero
Mar 11, 2013, 09:29 AM
Thanks for that. I needed a second opinion, as I find it difficult to tell the difference. Going to use 192, just wish I hade more room on my iPod to fit all my music. Thanks

Menel
Mar 11, 2013, 12:11 PM
It's subjective, every user is different.

For earbuds, 128kbps is going to be fine. That's what I do for my old nano that I use for running with buds.

For my iPhone that I use in car or dock in my big receiver. 256kbps, or it highs/lows get distorted especially with volume.

gnasher729
Mar 11, 2013, 12:11 PM
Thanks for that. I needed a second opinion, as I find it difficult to tell the difference. Going to use 192, just wish I hade more room on my iPod to fit all my music. Thanks

With 128 KBit/second, I find it hard to consciously hear a difference, but a lot of music is less interesting or boring.

DisMyMac
Mar 11, 2013, 12:19 PM
Questions from 2003....

TooLowToZero
Mar 11, 2013, 12:39 PM
A lot of my music is old stuff from the 60's & 70's, so I guess 128 is ok. Everyone has there own opinion and you get a biased opinion on the forum.

gnasher729
Mar 11, 2013, 01:43 PM
A lot of my music is old stuff from the 60's & 70's, so I guess 128 is ok. Everyone has there own opinion and you get a biased opinion on the forum.

Wrong. If you have music that is recorded with lots of noise, a lot of these 128 KBit are used/wasted to reproduce the noise, so you've got fewer bits left to reproduce the music. In other words, you may have more loss of quality than with a high quality recording.

dXTC
Mar 11, 2013, 01:46 PM
With 128 KBit/second, I find it hard to consciously hear a difference, but a lot of music is less interesting or boring.

That's because much of the audio processing that creates the illusion of "space" or "ambience" in a well-engineered recording is in the extremely high frequencies. Both AAC and MP3 tend to discard these frequencies in order to represent the overall sound in the more audible frequency spectrum using less data. This results in what is often described as "flat" or "lifeless" sound.

Example: The tracks on the CD release of Madonna's Immaculate Collection (volume 1) were re-engineered in QSound to give a "virtual surround" effect when played through regular stereo speakers. The effect is almost completely lost when run through lossy compression at rates lower than 256.

Antgb84
Mar 11, 2013, 02:06 PM
I use FLAC format with a set of quality earphones. 128kbit you can definitely hear digital artifacts. I wouldn't go any lower than 256.

DisMyMac
Mar 11, 2013, 02:08 PM
That's because much of the audio processing that creates the illusion of "space" or "ambience" in a well-engineered recording is in the extremely high frequencies. Both AAC and MP3 tend to discard these frequencies in order to represent the overall sound in the more audible frequency spectrum using less data. This results in what is often described as "flat" or "lifeless" sound.

Are there tricks or equalizer settings that can compensate? iMovie can adjust things according to room size- small, medium, cathedral...

dXTC
Mar 11, 2013, 02:17 PM
Are there tricks or equalizer settings that can compensate? iMovie can adjust things according to room size- small, medium, cathedral...

Unfortunately, such EQ settings will usually only amplify the artifacts left behind. That's the problem with lossy compression for many audiophiles-- the original recording's "soundstage" is forever altered.

It's like taking a relatively high-resolution picture, 1920 x 1080 HD for example, resizing it down to 720x480, then re-expanding it to HD. The blockiness tends to be rather apparent on the re-expanded picture, and any anti-aliasing filters won't help that much.

TooLowToZero
Mar 11, 2013, 03:14 PM
I have synced the same track at 128 & 256 bit rate to my ipod Nano. Played it over and over via my earbuds and concluded that the 128 recording is very similar, but sounds duller, or that's how it sounds to me.

During the London games last year, BBC Radio 2 reduced its output from 128 to 96 on digital radio and what a difference it made. It was like being played in the bathroom and distorted. I guess this is the same principal. I record a podcast each week and that is 128 off the radio in mp3, you can def tell the difference from music at 256 then.

Going to use 256 and reduce the amount of tracks I put on my Nano.

phrehdd
Mar 12, 2013, 03:39 AM
Something to think about -

If you have a CD and you convert a song to 256 and 128 - can you hear a difference? More to the point both 256 and 128 are compressions with loss.

When you take a 256 file it is already compressed and there is already loss and then convert it to 128 you get even more loss than say creating a 128 from a CD.

CD to Lossless - best
CD to 256 - excellent
CD to 128/192 - good
256 to 128 - mediocre and sometimes bad

As others have mentioned if you can't tell the difference then you have your answer. As for some of us - I can tell the difference right away on the same ear phones/plugs if the ear phones/plugs are medium quality or better.

Ffosse
Mar 12, 2013, 05:17 AM
Invest in a decent set of cans - all Skullcandy products are crap..

Then talk about file bit rate.

Gym Hellwig
Mar 12, 2013, 05:41 AM
You're going to ruin your hearing listening to music on a train without noise cancelling earphones.

aarond12
Mar 13, 2013, 10:28 AM
This topic has been beaten into the ground elsewhere... but apparently I need to remind people this:

128kbps MP3 is NOT the same as 128kbps AAC

I find 128kbps MP3 files unacceptably noisy while 128kbps AAC files are okay but not great.

gnasher729
Mar 13, 2013, 12:08 PM
As others have mentioned if you can't tell the difference then you have your answer. As for some of us - I can tell the difference right away on the same ear phones/plugs if the ear phones/plugs are medium quality or better.

Just remember: You may not be able to _tell_ the difference but still enjoy the higher quality music more than the lower quality. Without being able to say why.

Zwhaler
Mar 13, 2013, 01:15 PM
128kbps is a noticeable difference from 256. If you listen on crappy speakers you won't notice as much but anything in the car or half decent speakers/headphones you will notice!

phoenixsan
Mar 13, 2013, 01:53 PM
256 bit is the sweet spot between file size/quality. Having said the latter, it is my experience that higher bit rates can be appreciatted having a quiet environment, good hear and quality audio equipment.

:):apple:

SnowLeopard2008
Mar 13, 2013, 02:18 PM
Technically, 256kbps will provide you with better quality than 128kbps. Whether or not you care, hear the difference or otherwise matter to you in any way is totally up to you.

iEvolution
Mar 16, 2013, 05:15 AM
I convert to 128kbps AAC on my iPod Shuffle & Nano and find that the difference is not that big...unless I use my higher end head phones. In your case since you consider your phones to be "medium grade" then I think you'd be good to convert to 128kbps.

As one poster said, 128kbps AAC is not the same as 128kbps MP3 as the 128kbps AAC is superior to the mp3 format. Its not until you get up to 192kbps where the differences start to get smaller.

TooLowToZero
Mar 16, 2013, 06:37 AM
Thanks, I have loaded my Nano with 128 AAC tracks. I am not able to tell the difference between 128 & 256, with my headphones. When listening on the train and bus, or playing via my mini speaker, I must admit no difference for me. I have a little better earbuds than Apples own. Only ever tried Apples own the once and it was very poor sound. At least with the Nano I can fit all my 4,000 tracks on it. I would love something like the Classic iPod to hold all music at full bit rate, along with my podcasts. May consider iPod touch 64gb unit one day, but I have the iPhone 5, so a bit of a waste. Thanks for all your responses above.

Mr. Retrofire
Mar 16, 2013, 09:42 AM
I increase the sample rate in the iTunes encoder to 48.000 Hz and use 320 kBit/s as the encoding bit rate (see attachment). Joint Stereo (http://wiki.hydrogenaudio.org/index.php?title=Joint_stereo#Additional_information) is a lossless, channel difference encoding algorithm. If this algorithm finds similarities in the two channels, the algorithm stores only one copy of the signal. That means the encoder can store more information in this 320 kBit/s data stream, without a loss of quality. And before someone says 48.000 Hz is not necessary: Many audio decoders support 48.000 Hz, and in my experiments i can hear the difference between 44.100 Hz and 48.000 Hz (3900 more sample points per second).

dXTC
Mar 20, 2013, 10:09 AM
...
Joint Stereo (http://wiki.hydrogenaudio.org/index.php?title=Joint_stereo#Additional_information) is a lossless, channel difference encoding algorithm. If this algorithm finds similarities in the two channels, the algorithm stores only one copy of the signal. That means the encoder can store more information in this 320 kBit/s data stream, without a loss of quality.
...

(Bolding and snipping the above quote is my own; the text, however, is verbatim.)

I respectfully disagree that storing only one copy (one half of the stereo spectrum) is "lossless". Efficient? Yes. Lossless? Not entirely.

The article to which you link makes no mention of Joint Stereo being a lossless algorithm. Instead, it states that Joint Stereo may use several types of encoding schemes in the same file, in an attempt to achieve the best balance between compression ratio and quality at a given bitrate.

For a considerable amount of music that is recorded with all instruments panned center (i.e. placed close to the center of the stereo field), the most efficient way to compress this would indeed be to store one copy, with a lower-bit-depth side track denoting the minor differences between left and right signal. This, however, would turn out to be very inefficient on passages with different elements panned hard left and right (i.e. only come out either the left or right speaker); Mama Cass's "Dream A Little Dream Of Me", James Brown's "I Feel Good" and Howard Jones's "New Song" are examples of this.