I'm just wondering if anyone can suggest some really encoder-challenging samples I can use to test a few codecs on my system. Correct me if I'm wrong, but I'm trying to lower the settings I already use for my iPod (using Nero's free encoder v1.0.0.2) to conserve space. I figure a sample that pushes the limit of the encoder would be the best place to test, and then assume (*cringe* I know, I know) that everything else will work out alright.

My collection's pretty varied, but it's still probably pretty "mainstream." Anything anyone can suggest for songs and whatnot would be greatly appreciated (don't skimp now).

...And yes, I know it will differ from genre to genre. Forgive the ignorance, o fellow music-and-all-things-sound-related friends.

If your music is mainstream then you will probably be fine with 128kbps or 145kbps (I don't remember those two quality levels), I think they are -q 0.3 or -q 0.35. Some really hard samples would be classical music with a single harpsichord.

If you don't listen to classical music then don't worry about it. I also suggest looking at some heavy metal samples as those are often affected by decreased bitrates. Try encoding some songs from Slayer's Reign In Blood album: Angel Of Death or Raining Blood.

I wouldn't worry about trying to find those "killer samples." If you don't listen to classical or heavy metal then just try ABXing some of YOUR music at the bitrate YOU want, don't worry about other samples that may or may not fall in the genres of music you listen to. Some of these killer samples can easily be ABXed by some people even at 320kbps AAC. Don't pay too much attention to these samples.

Alright, thanks. I figured metal would probably be the most taxing on an encoder. I suppose classical music is difficult because it's really easy to hear the discrepancies.

I don't have any Slayer (I know, I know), but I've got some Dimmu Borgir and Fear Factory which might do the trick. I'll also check out some classical samples with my own two ears.

Cheers.

Check out the problem samples in the mp3 section, I would suggest fatboy (very difficult artificial robot voice), castanets (sharp attacks) and velvet (percussion).

I found it difficult to detect problems in metal music, because there is so much going on at the same time. The only thing sticking out would be the high frequency, hissing percussions.

I'll do that too. Thanks.

You're quite right about the high frequencies. They tend to be the sorts of things I notice the most, so it's probably crucial for me to find areas where they're affected most. Generally I don't have a problem separating instruments though, even in the chaotic world of metal.