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Radio Shack 33-2050 SPL Meter


Radio Shack 33-2050 Sound Pressure Level (SPL) Meter

Radio Shack 33-2050 Sound Pressure Level (SPL) Meter

Photograph 1: Radio Shack 33-2050 Sound Pressure Level (SPL) Meter

The analogue Radio Shack 33-2050 Sound Pressure Level (SPL) meter is useful for measuring sound intensity, determining speaker sensitivity or developing quick frequency response plots for loudspeakers. Power analogue SPL meter is supplied by a single 9-volt battery, which make the meter very portable portable. At the bottom of the meter is a screw mount which cab be used to attached the SPL meter to a tripod.

To create quick audio frequency response plots, one can use the SPL meter in conjunction with an audio test CD (test tone CD) and read the sound pressure reading directly from the SPL meter. For more detailed audio frequency response plots, you can use the Radio Shack SPL meter with a wide variety of commercial and free software packages. With this meter the Frequency Response Plotter Software with built in corrections for the 33-2050 meter noted in the Resources section below works well.

Radio Shack 33-2050 Sound Pressure Level (SPL) Meter

Photograph 2: Radio Shack 33-2050 Sound Pressure Level (SPL) Meter

When Used in conjunction with a Dayton Audio Woofer Tester 3 (WT3), this simple meter comes in very handy for working on DIY Speakers.


Correction Table - Radio Shack 33-2050 Sound Pressure Level (SPL) Meter

For more accurate results while testing loudspeakers, it is best to do the measurements outdoors in a quiet and spacious area. The Radio Shack Analogue SPL meter is not very linear and will need to be corrected. Use the following correction table with the meter set to "C" weighting and "Slow" response.

Correction Table - Radio Shack 33-2050 Sound Pressure Level (SPL) Meter

Frequency
Correction
 
Frequency
Correction
10 Hz
+20 dB
 
500 Hz
-0.5 dB
12.5
+16.5
 
630
0
16
+11.5
 
800
0
20
+7.5
 
1.0k
0
26
+5
 
1.25k
0
31.5
+3
 
1.6k
-0.5
40
+2.5
 
2.0k
-1.5
50
+1.5
 
2.5k
-1.5
63
+1.5
 
3.15k
-1.5
80
+1.5
 
4.0k
-2
100
+2
 
5.0k
-2
125
+0.5
 
6.3k
-2
160
-0.5
 
8.0k
-2
200
-0.5
 
10k
-1
250
+0.5
 
12.5k
+0.5
315
-0.5
 
16k
0
400
0
 
20k
+1

Projects Measured with Radio Shack 33-2050 SPL Meter

Resources - Radio Shack 33-2050 SPL Meter