How to convert dBu to dB
- 1). Determine what unit the decibel you are converting is referenced to. As we described above, if there is no unit attached to the decibel, it can be assumed to reference to one volt.
- 2). Convert dBu to volts. Divide the value of dBu into 20. Elevate 10 to the power of your previous result and multiply by 0.775. For instance, if you are converting 10 dBu, you would divide 10 by 20, which is 0.5, and elevate 10 to the power of 0.5, which is 3.16. You would then multiply 3.16 by 0.775, which is 2.44.
- 3). Convert volts to decibels referenced to one volt. Multiply 20 by the logarithm base 10 of the result from Step 1. Following our example, you would multiply 20 by the logarithm base 10 of 3.16, which is 20 times 0.39, or 7.78 dBV.
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