PASCO Specialty & Mfg. OPENER SPEAKER WA9900 Benutzerhandbuch

®

The Open Speaker is designed for the study of sound wave properties 
including frequency, amplitude, pitch, wavelength, and resonance.  
The rugged aluminum bracket holds the speaker perpendicular to the 
table and provides two standard banana plugs for power input.  The 
speaker is a 5 ¼” woofer with a polypropylene cone and high 
efficiency 10 oz. magnet. 

The Open Speaker is designed without a speaker cabinet to reduce the 
resonance of the air surrounding the rear of the speaker.  This helps 
students to more easily hear the resonance created in a closed or open 
tube of air.

Equipment Required: Open Speaker (WA-9900), Economy 
Resonance Tube (WA-9495), Function Generator (PI-9587C), Banana 
Plugs [SE-9750 (red set of 5), SE-9751 (black set of 5)] 

1.  Connect the Open Speaker to a function generator using standard 

banana plugs.

2.  Ask students to listen to the sound as you change the amplitude and 

to write down the property of the sound that is changing.  Help 
students to mentally connect the amplitude of a sound wave to the 
volume.

3.  Repeat step 2, but instead of changing the amplitude, change the 

frequency of the sound.  Ask students for the “music” term for 
frequency (pitch).

1.  Connect the Open Speaker to a function generator using standard 

banana plugs. 

2.  Place the Economy Resonance Tube (WA-9495) directly in front of 

the Open Speaker (See Figure 1 on the next page).