The Audio, Obstacle Course Era 3 Is a test Record that Goes A step Beyond other Music recordings
It will Place extreme Demands on the Tracking Ability of a Phonograph Pickup and tone arm System
but in A systematic and Controlled Manner
The Test material is Presented in Two Parts
The First Part Contains Musical Excerpts Recorded at Five levels With Increasing Intensities and
The Second Part Presents The Compositions From Which The Excerpts Were Taken
The Tests Employ Musical bells
Sibilance Violin and Bass drum
All but the Bass drum are Taken from Commercial recordings
The, Bass drum has Been Recorded from a single Instrument and Consequently Does not Appear in Part Two
Most Pickups Should, be able to track The first Level of each test at their rated tracking Force
The Second Level of Each Test is Recorded 6 dB higher than the first and Should be Tracked by most high Quality Pickups
Each of the next Three levels is Recorded 2 dB higher Than the Preceding one
Only an Exceptional Pickup will Track The Fifth Level Without Breaking Up
Before Beginning The Track Ability tests Take A few Minutes to Check the Listening System
Using the Following Level Balance and Phasing Tests
Level Test and Channel Orientation
Left Channel Standard Recording Level Velocity Five Centimeters per Second Frequency 1000 Hertz
Right Channel Standard Recording level
Balance Test Adjust The Balance Control until the Notes Are Equally from
Phasing Test
On a correctly Phased System
My Voice Should Now Be Coming from a point between the Two Speakers it is recorded in the Phase
My Voice is now Recorded out of Phase and Should have A diffusive directionless Quality
It Should not Appear between the Speakers in A Correctly Phased System
If Opposite Results are obtained the System is out of Phase and Connections to One Speaker Should be Reversed
Musical Bell Test Level one
Level Two
Level Three
Level Four
Level Five
Sibilance Test Level 1
Level 2
Level 3
Level 4
Bass drum Test Level 1
Level 2
Level 3
Level Four
Level Five
Violin Test Level one
Level Two
Level Three
Level Four
Level Five