I was using this codec for a while along with lossless formats (flac, ape, shorten) and I think it gives extremely good sound quality (compared with other lossy codecs). I always use the ”above braindead” (= quality10) preset because it was possible for me to hear slight differences in sound between other settings such as quality 6 and 8 (?!). When I compared the frequency spectrum of the encoded file (q10) with the original (or a lossless encoded one) it appeared that the high frequencies (above 20 kHz) were gone but the rest of the spectrum looked almost like the original. Also the sound quality of this compression compared for example with mp3 is much better (the frequency spectrum of mp3 is a totally disaster). Further, when comparing the ogg frequency spectrum with mac encoded file, both of them look almost the same but the higher frequencies in the ogg file (highest preset) are too much attenuated. For me the ogg always sounds to “harsh”.

I was wondering if there is any difference in sound quality between winamp plug-in 0.97f and the 2.0.70 version for Media Jukebox. I was using both of them and I think that winamp plugin gives a slightly better sound than MJ plugin. I do not know if it depends on the built-in equalizer (in winamp plugin) but the sound, especially the high frequencies seem to be a little bit clearer. Also the mid frequencies (such as voices) sound more like the files encoded with for example ape or flac (or the original). I wonder if any of you have similar experience.

Greetings,
dysprosium66

If you read around these forums a bit, you'll discover that simply comparing frequencies between audio clips is a poor way of judging lossy codecs. Here's a thread that combines a colorful multimedia presentation by Garf with some posts explaining why graphs really don't work.

So what does work, you may ask? Double-blind testing (DBT). If you compare the original and the lossy, without knowing which is which, you can get an unbiased analysis of whether you really can hear a difference. Never underestimate your subconscious bias!

You can get a DBT program from http://www.pcabx.com/ or from http://www.ff123.net/ (check out his ABC/HR program), and there are some more that I can't think of right now.

At HA, if you want to talk about problems you hear in audio, you HAVE to do DBT and post your results.

The frequency spectrum doesn't tell you anything about the quality of the audio file, watching it is worthless. I really doubt you can hear any difference at --quality 8, can you prove this?

I have to point out that I do always double-blind testing on encoded files. I randomly play the files and make notes about the sound (thus without “looking” at this files or spectra).
Further, one thing that is certain about frequency spectrum is, that if you are missing something of it, it will be not possible to recreate it during the playback or decoding (so if you will archive your music I will say use a lossless codec). (if you will hear the difference is an another question)

It is easy for me to me to point out the origin of compression. Sound characteristics of mp3, mpc and ogg really differ. The compression between q8 and q10 within mpc is difficult but possible on some material, especially on exellent recorded jazz and classic recordings (example: CD P.Barber “modern cool” ,various works of P.Wispelwey and so on).

If you're using an EQ, that could be the difference.

As far as I know, the output from the latest Winamp plugins and Frank Klemm's MPC decoder (which the MJ MPC plugin is based on) are identical. If you have noise shaping enabled in the MJ plugin, disable it and see if it changes anything.

Can you perhaps post a short (30 seconds or less) sample from a recording that you can ABX? If MPC fails at quality levels this high, perhaps more tuning is in order.

If you care to make this clip available, can you also provide your encoder/decoder settings and a description of the problem(s) you hear?

Thanks for your replay.
With disabled noise shaping both plugins "sounds" exactly the same for me.

I will try to do my best but at this moment I'm busy working on my new computer (probably with AOpen's tube motherboard) so it have to wait a while.






PS. I'd listened to my music (all kinds) thru MJ, terratec EWX 24/96, marantz 80 mkII (25W class A) amplifier and monitor audio Monitor 1 heritage