Recently, a lossless music streaming provider offered a quick online test to let you check if you and your equipment were ready to hear losslessly compressed music. There was just one problem.
The test didn't answer the question.1 2
To help you work out if you really can tell the difference between lossless and lossy3 music compression...
The Tidal test had you try to identify which of two versions of a track was lossless for each of five tracks.
This test will instead test whether you can tell the difference between the lossless and lossy version, without choosing which is which. It does this using an ABX test.
You will be presented with two reference samples (A and B), and a target sample (X). You have to decide whether sample X matches sample A or sample B. You will be administered multiple trials for each of the five tracks used in the original Tidal test.
The accuracy of the test will increase markedly as the number of trials increases. Although 5 trials is sufficient to estimate whether you can tell the difference between lossy and lossless, to work out which tracks you can tell the difference on will require 20 trials per sample4.
In this test, you will be presented with three samples: A, B and X. A and B are consistent, one lossless and one lossy. Each trial, X is randomly set to either A or B. You have to work out which one it is.
Start one of the samples by pressing the relevant button: A to start sample A playing, B to start B, and so on. Once the track is playing, you can switch between the samples by pressing A, B, or X.
You can seek through the tracks using the -5s, << (rewind), and +5s buttons, and stop playback using the stop button.
Once you think you know whether sample X is matches sample A or B, enter your choice by pressing X is A or X is B.
Then enter your choice by pressing the Next button.
Your progress through trials and tracks is shown at the bottom.
All buttons also have hotkeys. For QWERTY and DVORAK users, you should orient your hand left hand with your little finger on the A key, and your right hand with your index finger on the 8 key
Play or switch to sample A | A |
Play or switch to sample X | X, S, or O |
Play or switch to sample B | B, D, or E |
Choose that X is A | Z or ; |
Choose that X is B | C or J |
Seek back 5 seconds | 8 |
Rewind | 9 |
Seek forward 5 seconds | 0 |
Stop playback | - or [ |
Enter your response | Enter |