mp3 versus cd files

In my own personal experience, no difference on any MP3 at over 192kbps and 128kbps is more than acceptable. I have no formal music training and am tone deaf, though. Most of the musicians/audiophiles I know can't stand anything less than 256kbps. If you're just an average joe listener with a cheap (sub $500) stereo/headphones listening to average music (rock, dance, hip-hop, etc) MP3s will probably be completely acceptable to you.

In casual listening, I can't tell a difference between 192 and CD. I can definitely hear the difference between 128kbps and 192. 160 would be the bare minimum I would accept. V0 VBR (Variable bit rate) is my bitrate of choice (RIP oink). At 320, would be hard pressed to consistently identify a difference with CD, even in critical listening. At 192 I can guesstimate on a fairly consistent basis.

Either via Headphones (Grado SR80 or AKG K81DJ) through a headphone amp hooked up to the computer (Chaintech AV710 with Kernel Streaming via Wolfson DAC), or on a vintage speaker system (JBL studio monitors, Luxman seperates) through an iPod for MP3 and Denon CD player.

I also use VBR (I rip using AudioGrabber and LAME ... both freeware). I am not tone deaf; I have had some voice training at Temple University and I cannot tell the difference after 192kHz.

NB I have tinnitus from shooting without hearing protection, mowing lawns as a teenager and in general listening to my (cassette!) Walkman too loud when I was younger. So take that for what it's worth.

NB2 I don't have particularly high-end equipment. I use a Sansa e280 at the gym and a Creative Labs MuVo V100 for travel/home use.

Im not sure but i think 320 is overkill.

Ive been told that the cd qualitys equivalent is 192, so all that ripping at 320 does is make bigger files with no equivalent increase in quality. But that was a few years ago and not exactly an expert opinion.

I had my entire CD collection encoded in MP3 at 192kbps and cannot hear any difference at all when playing through my apartment stereo systems (granted the systems themselves are pretty cheapo JVC and Sonos stereos, so that may account for something...)

A sound engineer friend says 256 and over shoudln't make a difference unless you're very picky and have quite the high-end setup. Vinyls on the other hand have quite a noticeable *omf* missing from CDs.

LAME with the V2 setting (192kbps-ish files), and AAC files in the same bitrate range, are considered transparent in most cases according to blind listening tests performed by people over at hydrogenaudio. "Audiophiles" might say they can hear a difference but this is usually just BS. They say they can hear a difference between ultra expensive speaker cables as well, but there's currently a $1,000,000 reward for grabs to anyone who can prove it with a blind listening test.

There's an assumption here that pushing MP3 bitrates past 192 results in a proportional increase in audio quality all the way to 320 kbps. That's not necessarily true. Compressions tend to be less effective at the extreme ends of the spectrum. In the case of MP3, higher bitrates result in increased sampling over much of the frequency spectrum, but you will always have high frequencies chopped off in a particular way (I believe ~15.5kHz is the cutoff) regardless of bitrate because they are assumed to be outside of normal human hearing. If you're interested in pushing audio quality much past LAME's alt preset standard (variable bit rate generally between 192k and 256k), you should be using a lossless compression like FLAC, or just WAV. Storage is cheap.

I would say that my hearing is pretty good, I'm a hobbyist musician with some training, and I have no doubt that I can hear audible distinctions between high-quality MP3s and CDs. You do not need a $20,000 system, just something with reasonable amplification and a decent sized room. You may be able to hear a difference in spatial localization (which is compressed in MP3), smearing in percussive sounds (due to the undersampling), or changes in the nature of a sound due to frequency cutoff (like harmonics on a piano).

However, most of the time you will only notice the difference if you've got a poorly encoded file or you're doing seriously critical listening. Pop, rock, hip-hop--don't worry about it. Instrumentals, jazz, and stuff you're obsessive about--go lossless.

As an aside, CD bitrate is 1,411.2 kbps.

The lowpass for LAME's V2 setting is 19khz, so you probably have to have bat ears to hear any quality issues caused by this. You're right that higher bitrates don't mean higher quality though, because transparency is usually reached at bitrates well below even the 200kbps range. Well, for most music, it's pretty much impossible to hear a difference no matter how good the equipment is. But there's still some very rare problem sounds that won't ever be totally transparent due to limitations of the mp3 format, like castanets, which cause pre-echo even on high bitrates. The AAC format has gone a long way of removing such limitations though.

I can hear a very minor difference up to about 240, and its so minor I can't even place my finger on what the difference is, and it only appears with my really high end full range speakers. Absolutely no difference at about 192 through headphones, which is where i predominantly use my MP3 files.

If it's music that you're not interesting in hearing exact sonic reproduction in = 192k or 256 if you're picky If you want it to sound exactly like the CD = FLAC