Music Banter - View Single Post - BR Challenge Round 1 : Can You Identify the Lowest to Highest Bitrates?

SATCHMO · 11-09-2009, 08:08 AM

I have to say that this test seems flawed in some ways. First of all the increments between bit-rates are, before any other factors are taken into consideration, too small. If the test were a blind comparison between two samples of say 196 and 320 it would be incredibly easier to tell the distinction, but 4 samples of varying bitrates using a player that allows the user only a minimal amount of control when conducting side by side comparisons to narrow down the bitrates( eg. you can compare sample 1 with sample 2 fairly easily, but not adequately compare sample 1 to sample 3 without a lot of maneuvering with the player).

Another thing that should be pointed out is the choice of music that was used for the sample. It's been my experience that the type of music that most clearly demonstrates shortcomings in bitrate performance are those recording that have both very quick transient attacks (aka crescendos). and dense recordings that place a lot of demands on dynamic headroom (mostly agressive heavy metal). I have many albums that are at 196kbps that I'm completely happy with because the peaks of the recordings dynamic range fall easily within the parameters of that particular bitrates level of compression. There are some albums that I have had to go back and retrieve a new copy of simply because the album demanded more dynamic headroom than what the lower bit rate provided.

A great example of this is Mastodon's Crack the Skye. I have had a copy of this album @ 196kbps for a while, and it has always kinda bothered me that at hard transient attacks the music seemed to get "squashed" simply because the bit rate was too small for such a dynamically demanding recording. I went and retrieved a copy of the album at 320kbps and before I deleted the old file I decided to put it to the test. I told my roommate to play the two different copies of the same song, to play them randomly and to not tell me which one she was playing first. THe difference was obvious. The 320 example sounded fuller, like it had room to breath because that extra headroom was available during transient attacks. There was a noticeable lack of distortion and overt sense of heavy compression at musical peaks, which is exactly what I experienced with the original smaller file. The soundstage sounded more 3-dimensional and lifelike , and the signal to noise ratio also seemed dramatically improved.

11-09-2009, 08:08 AM	#7 (permalink)
SATCHMO Al Dente Join Date: Mar 2005 Location: Texas Posts: 4,847	I have to say that this test seems flawed in some ways. First of all the increments between bit-rates are, before any other factors are taken into consideration, too small. If the test were a blind comparison between two samples of say 196 and 320 it would be incredibly easier to tell the distinction, but 4 samples of varying bitrates using a player that allows the user only a minimal amount of control when conducting side by side comparisons to narrow down the bitrates( eg. you can compare sample 1 with sample 2 fairly easily, but not adequately compare sample 1 to sample 3 without a lot of maneuvering with the player). Another thing that should be pointed out is the choice of music that was used for the sample. It's been my experience that the type of music that most clearly demonstrates shortcomings in bitrate performance are those recording that have both very quick transient attacks (aka crescendos). and dense recordings that place a lot of demands on dynamic headroom (mostly agressive heavy metal). I have many albums that are at 196kbps that I'm completely happy with because the peaks of the recordings dynamic range fall easily within the parameters of that particular bitrates level of compression. There are some albums that I have had to go back and retrieve a new copy of simply because the album demanded more dynamic headroom than what the lower bit rate provided. A great example of this is Mastodon's Crack the Skye. I have had a copy of this album @ 196kbps for a while, and it has always kinda bothered me that at hard transient attacks the music seemed to get "squashed" simply because the bit rate was too small for such a dynamically demanding recording. I went and retrieved a copy of the album at 320kbps and before I deleted the old file I decided to put it to the test. I told my roommate to play the two different copies of the same song, to play them randomly and to not tell me which one she was playing first. THe difference was obvious. The 320 example sounded fuller, like it had room to breath because that extra headroom was available during transient attacks. There was a noticeable lack of distortion and overt sense of heavy compression at musical peaks, which is exactly what I experienced with the original smaller file. The soundstage sounded more 3-dimensional and lifelike , and the signal to noise ratio also seemed dramatically improved.