Monitor SPL vs. Full-Range SPL

I'll add only this, as freq's go down, you won't hear them as louder...probably, you won't hear them at all.

Deep bass is felt more than heard.

Dave

The point is, if a speaker has increased bass output because of increased FR range overall SPL will be higher. Consider this, if speakers are set to 80 db playing a 1kHz test tone, SPL will not be the same when playing white noise since the full range speaker plays deeper in the bass (audible or not, it will still measure on an SPL meter).
I am thinking bright speakers will be played quieter since subjectively they sound louder since bass notes are not heard but more felt.

The main problem with high SPL level is that it requires costly drivers that do not compress or exceed Xmax easily....this is expecially true in the bass and cost goes up almost exponentially as one desires high SPL at low distortion in the bass. However, this is rarely a criteria for consumer audio where levels are usually modest and do not have to playback music at realistic levels to artists/musicians or survive accidents such as a dropped microphone or as mistake in a patch panel.

Hi CDC, You are correct and what you are driving at is very important. If you are listening to your system at a reference signal of 83db at 1000hz and your system goes to 50hz the overall SPL of white noise (or music) will be less than if your system is capable of 20hz. 80db is most definatly not 80db for every speaker, for a white noise response. 1000hz is 1000hz for every speaker, but depending on the speakers freq response and the rooms ability to reproduce the rest of the freq spectrum, that is the rest of the story.

Who says you can't hear 20hz?

This is why I reccomend a specific listening level, that being 83db at 1000hz and tryng to get as flat and as low a freq response as possible as your system is capable of at this level.
Bob

Thanks Acoustat6 for getting what I was trying to say. Here's another novel thought.
I am thinking people have a "reference" volume level which is set at the ear's most sensitive frequency. This is ~3,000 hz I think and is the x-over point for many speakers. If someone listens at 90 dB, it would be 90dB at that frequency.
I know my B&W's have a 8+ dB spike at 3-5,000hz and that spike limited how loud I would listen. See, 80dB overall actually gave me 90dB at 3-5,000hz and that was too loud to my ears. So I usually listened at 70dB to keep that spike at tolerable levels.