Lossless vs 320kbps vs 256kbps, Moderation: no actual ABX results to see here. Options

[agatha1]

Hello everyone and thanks for making this forum what it is, I think the best audio forum in the world.

This is my first post here and I'm a little bit concerned about my ABX blind test results. I currently have over 6 TB of music, mostly FLAC and mp3 at 320kbps, but I also have some rips at 192 or below.

Now I want to standardize my whole collection and see if I can save a lot of Hard disk space or if I need to get better rips for part of my collection, etc. So, after some very interesting reading here, I decided to perform my own set of ABX blind tests, downloading foobar2000 and the ABX plugin.

Of course for some simple songs I can't tell any difference even between FLAC and 128 kbps, but I want a standard for my whole collection, including a lot of classical and progressive rock, so I need to find a bitrate that ensures me that I will ALWAYS have the best quality I can hear.

I tried the test first with Camarillo Brillo (by Frank Zappa), which I think it's a very good song for this test, because at the very beginning, after only 4 seconds, there is a kind of rattlesnake (sorry, I don't know the name of the instrument), which sounds definitely different at every bitrate. I encourage everybody to use this song for testing, as it makes it very quick.

Now, my results:
FLAC vs 256: I can always tell the difference, 10 out ot 10 times.
but here's the strange thing:
FLAC vs 320: Not clear
320 vs 256: Not clear.

¿Does this make any sense to you?
And if so, ¿Which is the bitrate I should stick to for my whole collection?

Thank you in advance for any help.

Regards from Spain,
Agatha.

[db1989]

1. Moved to Listening Tests
2. Post test logs, please
3. Using one song, and especially one with a specific type of artefact, is not an accurate way to predict the performance of a particular format/setting on your entire library. Test various tracks, genres, etc.

[agatha1]

Hi db1989,

1.- Thank you for moving my post to the correct sub-forum, and sorry for my mistake.
2.- ¿How can I do that? OK, I'll read more and try to find out myself, but thank you if you can help me here.
3.- I guess you're right, but also it makes sense to me that if the 'rattlesnake' in Camarillo Brillo sounds sooo different at 256 from its original FLAC, that means that 256 is no good to me ¿Am I wrong?

I don't have very good hearing, and I know that 192 kbps is more than enough for probably more than 80% of my entire collection, but if I ever decide to lower my whole collection bitrates, first I want to be sure that I won't be missing *anything* that I can actually hear, so I guess 320 is my minimum (?)

Also, the main difference in hard disk saving goes when downgrading from FLAC to mp3, so I think I will not test 256 or lower any more. Instead, I will confront FLAC vs 320 with other songs, to see If I can *ever* tell any difference, since I could not find any with my Camarillo Brillo test.

Thanks again and keep up with the good work!