SMWTMS Autosound

SMWTMS Test Form Becomes AES Standard  -by David Carlstrom 

The first SMWTMS Autosound Contest was in July 1984. Since the club had established the ABX method of consistent and reliable listening tests, we all wanted to compare car audio systems with as much precision. The difficulty is that a car audio system is not only a speaker and an amplifier to compare, but an acoustic environment as well. There being no practical way to instantly switch listeners from one car to another, David Clark stabbed at a solution that helps to focus the listner on separate aspects of sound quality. For the second SMWTMS Autosound Contest in 1985, David designed a form that lists the important aspects and asks for a rating of each on a scale of one to five. Over the following years, David has refined this form and the scores it generates to the point that it has been published as an Audio Engineering Society Standard, AES 20. 

SMWTMS Subjective Evaluation Form

(in the style of AES 20)

1.1. Coloration 
1.2. Octave to Octave Balance 
1.3. Balance, Bass to Treble 
1.4. High Frequency Extension 

|____________|

0                    100

2.1. Constrained or Open 
2.2. Lateral Stage Evenness 
2.3. Front/Back Stage Location 
2.4. Up/Down Stage Location 
2.5. Lateral Localization 
2.6. Depth Localization 
2.7. Image Stability 
2.8. Reproduction of Ambience 
2.9. Phaseyness or Excess Local Acoustics 

|____________|

0                    100

3.1. Veiled, Foggy, Fuzzy 
3.2. Ensemble Inner Voices 
3.3. Black Space Between Instruments 
3.4. Overclarity 

|____________|

0                    100

4.1. Transient Impact, Punch 
4.2. Loud Soft Capebilities 
4.3. Compression 
4.4. Strain and Annoyance Free Loudness 
4.5. Low Frequency Blurring 
4.6. Dynamic Modulation, Pumping 

|____________|

0                    100

5.1. Road and Aerodynamic 
5.2. Engine and Drivetrain 
5.3. Interference, Whistles, Clicks 
5.4. Rattles, Buzzes 
5.5. Flutter, Skipping, Fade, Hiss 

|____________|

0                    100