Default standard for speaker "sensitivity" measurement listings? Anechoic? In-room? Other?

It is my expectation that all measurements are anechoic unless otherwise stated.

For consumers A) They usually exaggerate and B) They are only useful as general, relative guidelines.

It's my understanding fewer are anechoic than in-room measurements. And, when revisions are made in subsequent versions of a speaker, one needs to ask if they truly went back and retested both anechoic and in-room measurements again.  

Sensitivity listed on a line item ad seems to be more of a general guideline at a selected frequency range noted on basic tech spec sheets. Seems to vary from one manufacturer to the next on what frequency they are sharing with you. Gotta look at the actual graphs across the entire frequency range to get a better handle on what's actually taking place with a speaker; where the dips and peaks are. 

I would say only 1% of speaker makers have access to an anechoic chamber. And extremely few of those have access to a chamber large enough to work below 100Hz. Even the few that do have chambers use them mostly for research and product development testing.

Most numbers from experienced manufacturers are calculated in half space, speaker on its back pointed up at the sky, no boundaries close by. That’s not easy to do either, as some just use a parking lot or roof top. Avoiding boundaries nearby is critical to avoid any gain being added by reflections of sound off boundaries.

This is the reason many manufacturers don’t bother, its not a level paying field as many products have deceptive measurements. Some more consumer oriented just put a spec down that sells speakers.

Brad

Jim Salk told me his measurements were anechoic because in room measurements are meaningless. I do not know how he does those measurements. Not sure how he would access such a facility. If he calculated in "half space" as lonemountain indicated, I would expect he would have used that phrase. Puzzling.

When I look at the measurements on the Salk site, none of them show anything below 200 hz. He may well be using a measurement method something like lonemountain describes. That is to take nothing away from his speakers, because I have found them to sound very good every time I have heard them.