different CD sources vs. computer mp3?!

[tpg]

I've been pondering and puzzling this and would like other opinions. It really bothers me... I've tried several different setups:

I ran my Sony CDP-CE375 CD player with optical connection to my receiver. Receiver is running in Direct mode (ie no sub, just full-range mains). The sound is thin and dry, lacking bass and emotion.

Next, I tried running the same CD through my PS2 connected to my receiver via optical connection, receiver running in Direct. The sound was actually better... but not exactly what I'd call full. It was more full, but not exactly there. The highs were a lot better, though. VERY clear.

I failed to try the CD in my computer running to my receiver... But I did try mp3's that were ripped off the CD in 320kbps. The computer is connected via digital coax to my receiver running in Direct mode, again. The sound is very full. Bass is solid, but not overdone. I've never heard my RF-3's sound this full. They always sound kind of thin regardless. The highs do suffer a tad with the mp3, though.

A summary:

Best bass/most full sound: computer playing mp3

Best highs: PS2

Worst overall: the dedicated CD player

I am not bashing the CDP here... just wondering what I might do to fix this problem. I cannot understand why it wouldn't sound quite right. I guess dynamic range comes into play somewhere?

Any thoughts or suggestions are appreciated... I've been very confused over this.

[DrWho]

What you're probably experiencing is the limited bandwidth, limited dynamic range, and compression inheritant in MP3's. The first thing to go on an mp3 is the extreme high frequency response. However, this can be a good thing as the highs on almost every recording just plain suck (my opinion anyway). Correspondingly, a reduction in the highs results in the overall sound being fuller (to an extent).

Have you tried running the analog outs from your various players into your reciever? I have tried the optical cable on the PS2 as well and I feel that it's analog outs have always sounded better.

Anyways, I think that after a while that the wow factor of the MP3 will wear off and you won't find it so pleasing anymore. However, if it's something that you observe long term, then maybe there's something wrong with your CD player.

[KungFuNat]

there are a coupple possibilities i see.

the most simple solution that i can see is try using the digital coax cable with your cd player and see if that makes a difference. digital should be the same regardless of optical or coax, but perhaps the actual connections or digital pathways in your reciever could be different depending on which connection is used. perhaps your optical cable is damaged or not up to snuff.

i also think that its the sound of the MP3s themselves that you enjoy. you must realize that mp3 is a lossy codec that colors the sound of the original digital audio. it will limit frequency responce and sometimes gives the audio a pleasing "compressed" sound. basically if you like it, then its all good. just realize that this is not an accurate reproduction.

there is also the fact that sound comming through a computer, even digital out, is up-converted to 48khz before exiting the computer. normally thats not a problem, but the algorythm that is used in windows was designed for efficiency not quality, and will also negatively color your digital output. the only way to bypass the windows "kmixer" is using a sound card that supports ASIO output over the spdif(digital) connector. this is usually reserved for more professional sound cards, although it can be achieved with many different cards. bypassing the kmixer will send a true bit-perfect 44.1khz signal out to your reciever, but this may again lead to the dull sound you are describing.

so basically i would try a cd-player with a digital coax output, if your cd-player doesnt support this perhaps you know someone who would let you borrow thiers, or perhaps try picking up a better quality optical cable and see if there is a difference. if you find no difference, then my only suggestion for you is to perhaps purchase an external DAC and run an analog signal from the DAC to your reciever.

[powdermnky007]

The DAC in your reciever might suck. What kind of reciever is it?

Try using that analog outputs of your cd player.

It seems I read somewhere that coax digital is supposed to sound a little better than optical. I know that is flame bait, I've never tried it. But just read it somewhere for those two cents.

[maxg]

Whether the DAC is poor or not does not seem to be the issue as from what I can see all 3 connetions use that DAC.

The computer connects to the DAC via coax whilst the PS2 and the CD player connect via optical - correct?

If I got that right then it just might be that your coax installation is merely more successful than your optical (Bad cable? Bad port on one or other of the units?).

I would try connecting either the CD player or the PS/2 via coax initially to see if it makes a difference. I dont know if either is possible (i.e. whether either the CD player or the PS2 have coax ports to use.)

I would also certainly try using a pair of RCA's for an analogue connection from any or all of your sources.

If the RCA connection sounds better than the digitial alternatives, then, it is probable that the DAC in the player is better than the DAC in the receiver.

Just as a side note - I have heard more than one person tell me that the PS2 is actually quite a good CD player. Not only that there is a tweak that makes it even better involving cutting a connection on the DSP somewhere. Dont try it unless you know exactly what to do - I am clueless and it sounds like a recipe for writing off a PS2 but if you find someone who has done it....

[Marvel]

NatGun,

I believe that only a Soundblaster chipset will upsample to 48k before sending it out. Most sound cards do not. Actually, I found that many consumer soundcards do upsample to 48khz. Some in hardware (SB cards) and some in software. The kmixer only resamples if there are streams with different sample rates hitting it.

Marvel

[cyclonecj]

Some computer sound cards also have a bass & treble control. Is it possible that you have them enhanced, instead of set to flat?

[tpg]

I'll try the analog outs first chance I get. I plan to upgrade receivers fairly soon, anyway, so maybe that'll fix the issue while still allowing me digital connections for all. I am running an Onkyo right now.

For my computer sound, I have a SoundBlaster Audigy MP3+ which I am using to upsample into 96kHz to my receiver. Apparently it works- my recevier recognizes the 96kHz and displays it anytime you try to leave stereo mode.

Also, absolutely NO chance that any EQ is changed on anything. I absolutely hate EQ's and have always had bad experiences with them- either poor sound quality or long-term damage to speakers from them. My dad is a heavy EQ user because he fried his high-frequency hearing. I cannot stand the sound, nor the hiss the speakers make when cranked like that.

I'll do some testing...

[KungFuNat]

marvel,

the only soundcards that do not upsample natively without the ASIO plugin or kernel streaming are RME pro-recording cards. i think the base model goes for something like $600 new. ALL other sound cards will resample up to 48khz using kmixer, unless the aforementioned ASIO or kernel streaming is used. some cards will allow a 44.1khz stream output, but this is resampled by kmixer and then downsampled by the card itself before output. the problem is microsoft itself in this case. in order for a sound card driver to conform to the WDM driver model, it MUST utilize kmixer to upsample. the soundblaster cards have no upsampling hardware on them, the output DAC simply only outputs 48khz. even if you use kernel streaming, the card reverts back to kmixer because it cannot accept anything but 48khz.

there are many options in order to achieve ASIO output that preserves a bit-perfect audio stream, but it takes special software and configuration to do so.