dB/W/M conversion - M vs 0.5 M ??

[MadMutt]

After many hours of hunting, I found some very basic specs on a set of drivers I'm intersted in.

BUT, they are quoting the sensitivity as 97 dB/W/0.5 M

So, is it possible to convert this to the more common dB/W/M ??

Even if someone can give me a vague idea of what they could come out as I'd be gratefull.

Doubt it matters but just in case;
The speakers are actually a set of car audio seperates.
Peerless P822000


Thanks......

[Nanook]

intensity varies as 1/R², where R is the distance in meters (or feet) from the source.

So:

1/.5²=1/.25=4
1/1²=1

so at .5 metres the intensity will be 4 X's as much at 1 metre.

and a power factor of 10 is needed to double the apparent loudness

what does this mean to you? At 1W@1m, you will be effectively lowering the sensitivity to 91dB.

stew

[MadMutt]

Maaany thanks.

Exactly the info I was after.

Wasn't expecting an answer for days.

[Svante]

Subtract 6 dB per distance doubling.