Trying to convert absolute volume on my receiver to relative volume

[Dazed_and_confused]

I have a Sony STR-DN1050 receiver. The volume goes from 1-74. I would like to know if there is a way I can convert this absolute scale to a decibel based relative scale. For example, what number between 1 and 74 would be equivalent to 0 dB on a relative volume scaled receiver?

 

[macddmac]

Not sure on Sony- in setup menu on most receivers

 

[Dazed_and_confused]

I don't see anything in the setup menu. I decided to try an experiment. I played the band limited pink noise test tones from my Disney WOW disc and noted the SPL in dB from my left front speaker for each volume increment. Well, I only went as high as 65 on the 1-74 volume scale as I was afraid I might blow a speaker. This reveals that I hit 75 dB at 41 on my volume know and 85 dB at 59. I recorded these values about 5 feet from the speaker. With this information, is it possible for me to determine what absolute volume number on my receiver would correspond to 0 dB on a relative volume scaled receiver?

Also, would I be okay in finishing off my test? Can I safely record the dB values on my volume knob as I go from 66 all the way to 74? My speakers are rated to output 103.8 dB at RMS power. Given that I'm taking these measurements about 2 meters from the speaker, I can adjust my SPL values 6 dB higher for what SPL the speaker is actually outputting. So, if my speakers are rated to handle 103.8 dB RMS (106.8 dB peak), it seems as long as my SPL meter isn't going over 97-100 I should be safe from blowing my speaker when playing the pink noise test tone at maximum volume. Is this correct?

Hope I explained what I'm trying to do clearly.

 

[WaynePflughaupt]

With this information, is it possible for me to determine what absolute volume number on my receiver would correspond to 0 dB on a relative volume scaled receiver?

You can’t. You’re confusing two different dB scales. The in-room measurements are an acoustical noise measurement that is dBSPL (sound pressure level). The dB markings in a receiver are dBV, which is a voltage gain indication. If the receiver’s volume control (voltage output) tops out at a value of 0 dB, and the scaling below that is given as a negative value, such as “-25 dB,” it indicates the volume is set for 25 dB the below maximum voltage output.

Thus dBV has no bearing on dBSPL. At a given dBV setting on the receiver, you will get different dBSPL readings in the room using different speakers with different efficiency properties.

Regards,
Wayne A. Pflughaupt

 

[Dazed_and_confused]

Do receivers with a decibel volume scale top out at 0 dB? I thought 0 dB was maximum clean power on a receiver and that anything above 0 dB introduces distortion? Is this wrong?

 

[WaynePflughaupt]

Hard to say, as there is no universal standard. Some receivers’ settings go beyond 0dB to (+) indications.

Regards,
Wayne A. Pflughaupt