#506 Lame 3.100 VBR V0 psychoacoustic problem - Foobar ABX test included

[Jari Aalto]

DESCRIPTION

The lame 3.100 -V0 causes artifact in electric music for the kick drum. The characteristic of the artefact is added "chat", like in a hi-hat. The best place to detect this is to listen are 0s-3s repeatedly and concentrating on the kick drum.

ENVIRONMENT

Debian tessting 64bit. Lame package 3.100-2+b1
https://packages.debian.org/testing/lame

OPTIONS USED

Certain, under ABX, that the artifact is there:

lame -V0
lame -V0 -Y

Uncertain, if the artifact is the under listening test:

lame --preset insane

ADDITIONAL INFO

This case was reported 2019-12-22 in post "DIY:
Blindtest MP3 V0 / 320 vs FLAC (including audible results)"

• Setup: LAME 3.100 MP3 V0 (and CBR 320) vs FLAC
• ABX Foobar test result; https://pastebin.com/wCaHdket
• Files: https://mega.nz/#!JeBFHCAB!yCCHmiKPs7ITOecVuud09e7nK31RCLuueGPw2vyGryg
• Thread: http://www.hifi-forum.de/viewthread-54-19808.html?fbclid=IwAR2tF_Ko1tMIYsr-RhDZ-x_Slv89qDf-2rYcjr3ETXlLb4lBtbizRHkDK0I

PERSONAL TEST

I verified the result under Foobar ABX. Could indentify the artifct 100% (10/10) quite fast.

foo_abx 2.0.1 report
foobar2000 v1.3.20
2020-02-09 11:36:17

File A: CodecTest 16bit.wav
SHA1: 86786351d337f5065444a841bf07f1b2319869c1
Gain adjustment: -3.67 dB
File B: CodecTest VBR 0.mp3
SHA1: f9b4f13b50c379509242865097305f20af9fb4de
Gain adjustment: -3.67 dB

Output:
DS : Primary Sound Driver
Crossfading: NO

11:36:17 : Test started.
11:36:37 : 01/01
11:36:50 : 02/02
11:37:07 : 03/03
11:37:24 : 04/04
11:37:35 : 05/05
11:37:47 : 06/06
11:37:59 : 07/07
11:38:15 : 08/08
11:38:33 : 09/09
11:38:49 : 10/10
11:38:49 : Test finished.

---

Total: 10/10
Probability that you were guessing: 0.1%

-- signature --
a32c26e90a844144b3b6bc539216df2b091d60ac

[Jari Aalto]

Upgraded Debian packages and did the test with slightly never LAME

$ apt-cache policy lame
lame:
Installed: 3.100-3
Candidate: 3.100-3
Version table:
3.100-3 500
500 http://deb.debian.org/debian testing/main amd64 Packages
100 /var/lib/dpkg/status

Result: test under ABX Foobar yield same as with the previous 3.100-2+b1. The artifact is detectable.