Criticisms for iPod's sound and what are the Physics reasons why?

[kasrhp]

I found everything out about differences in SQ between players when I upgraded to some pretty good headphones. I noticed how different, weak, inaccurate, and lifeless my ipod video 30gb sounded compared to the music from my laptop. The laptop using normal media players, with or without an equalizer set sounded good, full, and rich.

I then started comparing the bitrates of the songs, and before you know it, came to the conclusion that my ipod, no matter what was on it(lossless to 128) sounded bad, real bad. Then, I found this site. I started to ask a bunch of questions, and start doing my research.

Found out that my Sansa clip was a great sounding device(it wasnt my ears playing tricks on me). I was amazed a $50 player sounded better than my $250 ipod. Then, I received a Cowon O2 for Christmas(from the wifey) and fellin love with the rich detailed SQ. Now, im not an audiophile, but I think I am on my way. I cant even listen to a poorly recorded track anymore. It bums me out.

So, thats how I figured this all out. Kinda random, but ya gotta love it.

[CrowdAds]

[musichound]

I think the lot of you are missing the most important spec: The THD of the amplifier (Total Harmonic Distortion) If the THD is high, regardless of phase shift, roll off, etc, it would sound bad, period. The lower the THD, the cleaner the SQ.

[sumx4182]

Originally Posted by saratoga

It sounds to me like you're probably confusing the clip with some other player, but post the results if you've got them handy. I'd be interested in seeing them.

I wasn't necessarily speaking about the Clip, but players in general.

[Enigmatic]

Originally Posted by musichound

I think the lot of you are missing the most important spec: The THD of the amplifier (Total Harmonic Distortion) If the THD is high, regardless of phase shift, roll off, etc, it would sound bad, period. The lower the THD, the cleaner the SQ.

Total harmonic distortion is often overrated. Please see, for example, http://www.soundandvisionmag.com/ass...rInterface.pdf, PDF page 2:

With most music you can’t hear ordinary harmonic distortion unless it’s well over 1 percent.

[dfkt]

Originally Posted by musichound

I think the lot of you are missing the most important spec: The THD of the amplifier (Total Harmonic Distortion) If the THD is high, regardless of phase shift, roll off, etc, it would sound bad, period. The lower the THD, the cleaner the SQ.

Well, if it's the "right" kind of THD, meaning tube-style harmonic content distortion of the overtones, it might actually sound pleasing to human ears... I'm kidding, of course - you can't expect portable players to do that on purpose.

[saratoga]

Originally Posted by musichound

I think the lot of you are missing the most important spec: The THD of the amplifier (Total Harmonic Distortion) If the THD is high, regardless of phase shift, roll off, etc, it would sound bad, period. The lower the THD, the cleaner the SQ.

This is nonsense. The most important spec is the one that dominates. THD is so low on most portables its well below the noise floor, and thus its often irrelevant.

[saratoga]

Originally Posted by sumx4182

I wasn't necessarily speaking about the Clip, but players in general.

So you posted to tell me that there are players with bad sound? Thanks? I guess

[sumx4182]

Originally Posted by saratoga

So you posted to tell me that there are players with bad sound? Thanks? I guess

You need to calm down a bit. The OP was referring to physical reasons why some players sound worse than others. I was speaking in generalities as to why one player will sound worse than another. Physical reasons why mids are too high, or bass is absent. So in fact, it was the rest of us attemping to answer the original question.

It does so happen that the Clip is one of the few players with very little roll off above 20Hz. Look at the graphs DFKT posted and you'll see that the Clip does roll off very little but other players that sound "good" to people's ears do have significant roll off above 20, even above 30 or 40Hz all the way to 175Hz. That will certainly have an effect on the bottom end of the sound.

[saratoga]

Originally Posted by sumx4182

You need to calm down a bit.

I am calm. Why would you think I'm angry? Mostly I'm just confused why you quoted me at all if you weren't talking to me!

Originally Posted by sumx4182

The OP was referring to physical reasons why some players sound worse than others. I was speaking in generalities as to why one player will sound worse than another. Physical reasons why mids are too high, or bass is absent. So in fact, it was the rest of us attemping to answer the original question.

I think I already answered the OP pretty well. At this point I'm mostly just explaining to you the reasons why roll off happens so that you don't mislead the OP.

This is why I quoted you and not the OP! (Though hes welcome to read along and pitch in if he likes)

Originally Posted by sumx4182

It does so happen that the Clip is one of the few players with very little roll off above 20Hz.

The Clip has no roll off, look at the graphs posted.

Originally Posted by sumx4182

Look at the graphs DFKT posted and you'll see that the Clip does roll off very little but other players that sound "good" to people's ears do have significant roll off above 20, even above 30 or 40Hz all the way to 175Hz.

Yes as I said above, most people are quite bad at determining what sounds best to them. Even large differences in bass response can easily go unnoticed to many people unless they know to look for them.

Its sort of the paradox of learning about audio. The more you know the less happy you become

[Enigmatic]

Originally Posted by sumx4182

Look at the graphs DFKT posted and you'll see that the Clip does roll off very little but other players that sound "good" to people's ears do have significant roll off above 20, even above 30 or 40Hz all the way to 175Hz.

MP3 players often sound good to people’s ears, because typical music often has very little happening below about 50 Hz.

[sumx4182]

you'll notice though that those graphs have some roll off approaching 200Hz...it may not be at half power, but still...

[saratoga]

Originally Posted by sumx4182

you'll notice though that those graphs have some roll off approaching 200Hz...it may not be at half power, but still...

I think you're looking at the wrong graph.

http://rmaa.elektrokrishna.com/Compa...20Vibez/fr.png

The clip is the one in white.

[Blahaha]

All I know is my S9 has a Flux Capacitor...1.21 jigawatts baby!

[sumx4182]

I was referencing Enigmatics post, not yours! I know how to read a graph. Yes. The clip has very little roll off. A bit, but not anything noticeable. I was talking about the D2, which many say is an awesome sounding player yet the graph has considerably steep roll off that starts around 200Hz. The Vibez actually starts to drop above 500Hz. but has a much less steep drop until it passes the D2 and the bulk of it's rolloff is down at around 100Hz. To me, those are numbers can be indicitive of whether or not a player has faithful sound reproduction. A bass guitars low E is roughly 41Hz. A 5 and 6 string bass has a B note around 31Hz. And the beauty of music is that even if a string doesnt vibrate at that low of a frequency, the way the notes mix, add, and cancel will cause signals at different frequencies than just the true notes frequency. If you limit the highs and the lows, you're not going to get the fullness of the music. You can see that when you encode at a low bitrate (the extreme highs and the lows are usually the first frequencies cut off to save space) and it's no different if a player suffers from roll off in the lower range.

[saratoga]

Originally Posted by sumx4182

I was referencing Enigmatics post, not yours! I know how to read a graph. Yes. The clip has very little roll off. A bit, but not anything noticeable.

Thats not a roll off, its just the response of the ADC recording it.

Originally Posted by sumx4182

I was talking about the D2, which many say is an awesome sounding player

Its really not. Most threads around here seem to consider it pretty average. What people like is the EQ, which is very powerful.

Originally Posted by sumx4182

To me, those are numbers can be indicitive of whether or not a player has faithful sound reproduction. A bass guitars low E is roughly 41Hz. A 5 and 6 string bass has a B note around 31Hz. And the beauty of music is that even if a string doesnt vibrate at that low of a frequency, the way the notes mix, add, and cancel will cause signals at different frequencies than just the true notes frequency. If you limit the highs and the lows, you're not going to get the fullness of the music.

For what its worth, you usually need 1-2dB of difference before its audible and most headphones really aren't going to go down much past 50Hz anyway, so most of those players would have a similar bass sound to them I think except maybe to a very experienced listener.

Originally Posted by sumx4182

You can see that when you encode at a low bitrate (the extreme highs and the lows are usually the first frequencies cut off to save space) and it's no different if a player suffers from roll off in the lower range.

Highs are cut when you use low bitrate, usually not the lows since that wouldn't save any space.

[sumx4182]

So you're saying you won't hear a low E bass string played open through headphones?

[dfkt]

You might not hear the 41Hz fundamental at its full volume, only the overtones.

[sumx4182]

at it's full volume, I'll give you that! haha

[liluoke]

i gotta read all of this after my midterm, hahah

[gcogger]

Originally Posted by liluoke

What are the physics reasons for something like a ipod having "inferior sound"?

A song has numerous sounds, which are frequencies. When a DAP like the ipod, samsung P3, or whatever play a song, what exactly is going on that makes one play sound "superior" to another?

Commonly cited reasons are inferior bass (what does this really mean in physics terms anyways? a high amplitude low frequency sound? why can't every player produce this?), "better midrange" (again, what does this REALLY mean?), and flatness of spectrum (does this mean all frequencies of the sounds are at the same amplitude?)

I tried looking in the geek section, but I find no discussions on what are the phenomena that occur making one player superior to the other and the scientific reasons why, so I thought of starting this thread.

Whoever would like to contribute, please do so! You may assume that I have an understanding of basic wave properties.

If some guys on a forum could tell you precisely what makes for good sound quality, I think the entire hifi industry would be out of business It's not a simple thing to tie down...