128 or 192 kbps for cds?

[cpgoose]

Hi,

When you get an mp3, should you get 128 kbps or 192 kbps?
If you get a 192, you shouldn't convert it to 128, right?...won't that
mess up the quality?

Thanks!

[Conquest10]

128 is cd quality.

[tgpo]

128 is cd quality.

No mp3 is cd quality.

You won't be able to hear a difference between 128 and 192 if both are properly encoded.

[sterno]

Encoding tracks from CD with lame I find that I can hear a difference between 128k and 160k, but I hear very little difference between 160k and 192k. That said, the quality of your MP3 decoder, sound hardware, and speakers probably has more effect on the quality than 128k vs. 192k.

[vcd4me]

sterno is right

The equipment is the key.
Also it can be up to the listeners' ears.

BTW Personally I think you should go with 320K but no less than 160.

Conquest10,
320 is the closest to cd quality, 128 is near cd quality

cpgoose,
Yes the quality of course will get worse, but what you didn't tell us what you were doing with these mp3. If you have an mp3 player and are going to put these mp3s on a cd in mp3 format then the lower the bitrate the more tracks you can fit on a cd.

Hope this helps
VCD4ME

[vitualis]

I can definitely tell the difference between the original CD and MP3 at 128 kbit/s CBR even encoded with the best encoders (i.e., LAME or Fraunhofer at this bitrate).

Something of the order of 256 kbit/s is probably transparent to almost everyone on all equipment (unless the MPEG decoder is broken) and YOU will probably not hear the difference from 192 kbit/s upwards.

IMHO, LAME on the --r3mix setting is pretty damn good.

Regards.

[sterno]

One thing I've found with quality is that winamp's output is not as good as some other players, especially in older versions (I haven't tried winamp 3). It has a tendency to clip high tones, like you find in orchestral or vocal material. Most encoders also tend to clip high tones, so you get a hit twice in the same range. How noticable it is (if at all) will depend on the material.

[EddyH]

128k is definately not CD quality. Not at all. Unless you've got one of those 'oops' discs that appear to have been mastered from mp3 or a really old minidisc recorder with an early ATRAC version (Ministry of Sound, i'm looking at you...).

All the same, that's the quality I use for making my mp3s from my own albums, to put on CDR for the DVD player. Why? Because it's 'good enough', especially for listening at moderate volumes without headphones. I tell the encoder to cut everything above 16khz and the headroom be damned.... if I want better quality, well, it's only a short trip up the stairs to get the original PCM material
It can even do ok for mp2, though 160 or 192 is far better with the older format.

It doesn't take up reams of space on the CD (a fairly predictable 12 hours per disc) or for downloading, but doesn't sound like total ass. People who encode at 112 or 96k get on my nerves But so do those who insist that you can never go below 192k. I tried out Lame, put it on decent quality VBR, and saw many of my recordings double in size, though I could no longer tell them apart from the original CD even with much straining. I think I'll leave re-encoding everything to that quality for another day, such as when I have a 200gb hard disk and a DVD burner. Getting 6 hours on a big ol' CD isn't worth it right now when I can get 2.5 of comparable quality on a much smaller minidisc. But 30+, much more agreeable

(I got 60+ gigs as it is!!)

[EddyH]

Sterno the high tones being clipped is probably an intentional feature of encoders eg like Musicmatch jukebox that will lowpass low rate mp3 output at around 16khz, to make sure that the most important segment of the audio spectrum can be encoded well, without having to sacrifice bits to a range many people won't even hear. Many inputs, such as FM or digital radio, and TV, don't go much above 15khz anyway so you shouldn't notice too much.

Orchestral recordings going above 16khz? I don't see that a lot They tend to be the least demanding of all, particularly as the average reference encoder appears to be written by a load of classical music freaks.

(for comparison, general spectral ranges.. let's pretend all of them go down to 20hz ok.
CD = 22khz, generally filtered to 20khz in the studio.
Lame's best quality setup = "19.5khz" max which seems to work out in real life to 18.8.
Modern minidisc short-play similar, 15 to 20khz variable with a usual max of around 19. MDLP 2x mode = 17.6khz, which is good for 132kbits, 4x mode = 12.4khz, which is horrible for all but basic recordings... still excellent for 66kbit though.
Old TV broadcasts around 12khz, up to 15.7 if you were lucky. Digital audio streams on TV (eg nicam, DD) about 15 or 16.
FM radio used to be 19khz if technical things haven't lied to me, but now it's a rather flat sounding 15khz, possibly to stop comparisons with digital / XM showing up the new system's severe lack of treble, from also using a 15khz max.
Audio cassettes are variable, but a decent general purpose one such as TDK FE should manage 16khz plus a little; rubbish ones, including some that masquerade as being high quality (CD-its..) may only get 11-12khz; proper high quality ones may hit 20khz at times.
DVD generally subject to the same filtering as CD despite it's increased sample rate, and may even have dispicably low maximum frequencies.... however occasionally a nice one comes along like the flaming lips' latest dvd single which has a spectrum that's visible on the graph all the way out beyond 23khz!
TMPGEnc and other such low-treble mp2 encoders get into trouble past 14khz and have quite a bit of horrible squelch up to 16k, rarely getting beyond it even with high rates. GNU mp2 encoder goes up to as much as 20.5khz for 224k+, making it fantastic for re-doing music videos using the source album CDs, or 18.8khz for the majority of other modes; again, like mp3, anything below 160 or 192k is really better off with a 16khz or less (14.4 for 112..) low pass filter.)

So you see, it's all really just in your head

Winamp, as far as anyone who has done tests can tell, has hands-down the best decompression and playing, the best sounding and most accurate. Nullsoft went through a patch in the early-mid 2.x versions where they switched to a different and experimental decoder and it all went pear-shaped so the old one was reinstated. I use it for decoding compressed material when needed and where possible as it's quick and appears to give the best results. If you're finding the treble is being dulled by winamp when it's not being dulled by other players with the same source file, maybe the EQ filter has been turned on and has the treble cut template loaded. Some of the preset curves are a bit cooky to say the least, such as the Classical template which appears to be a concerted effort to knock out any frequency above 12khz.

If the source was clipped say at 16khz, and winamp does it again with the EQ or decoder, that's not going to count as a hit twice in the same range. Unlike the average 'soft' analogue low pass filter, encoders tend to display a 'hard' low pass where everything under the filter frequency = 100%, anything over = 0%. When I filter 'by hand' I may have a slide over 800hz-1khz from 100 to 0, but software tools are not so ear-friendly. But this does make it being hit in the same place impossible as there's nothing left to hit.