What are the specs of a full range speaker?


I've noticed that this term is used pretty loosely around here and I'm wondering what you think of when you read it in an ad. What does "full range speaker" really mean? Is it 20Hz to 20 Khz? I've always considered it to mean a speaker that reaches down into the 30s with some weight. What's your interpretation?
macrojack
Dave...

In your response to Bartokfan

>>>...-3db at 45hz would mean bass output (SPL) has dropped by around half at that freq<<<

Is there anyway to tell at what frequency the speakers output is flat?
I have to agree with Mdhoover and some others who are arguing against the "greater frequency reposnse is necessarily better" viewpoint.

Quality reproduction in the 80 to to 12Khz range is more desirable than a speaker that is "flat" from 20 to 20 Khz but suffers from significantly more harmonic and IMD distortion.

Furthermore, an SPL meter and a test CD will give practically everyone who owns a speaker with a flat reponse from 20 to 20 KHZ a surprise....as most rooms have between 10 and 20 DB response fluctuations (peak to trough) below 80 HZ. This is unavoidable and is caused by standing waves....room treatments can help some but fundamentally some fairly big bumps will remain unless they are equalized out, and then, even equalized, the reverberation problem remains and any EQ'd flat response is limited to a small sweet spot.

A further problem of a speaker with flat extended LF response (no roll off) is that LF frequencies radiate in ALL directions...therefore they reflect off the rear wall and will boost by +6db at some frequencies and will cancel out a quarter wavelength from the wall (producing more frequency response bumps in addition to room modes)

Which all goes to show that flat frequency response down to 20 Hz may not necessarly be a good thing in a speaker.
My experience with with sub 30 Hz in music is limited to just two audio systems, and our piano. When my wife is pounding out Grieg there is a lot more surfaces involved than the vibration of coiled wires.

I have a friend who is a conductor. I helped her find a house in Sacramento years ago. She had two requests. The house had to have a room big enough for her baby grand, and it had to have a wood floor.

If you want to hold a grand piano concert in your house, then you better have the real thing or speakers that can put out the power, and range of that piano.
Muralman1, I agree, and then some.

The real thing is the only thing! No audio system will ever come close, not by a great margin, to ever reproducing the dynamics and power of a grand piano. Anyone who thinks otherwise hasn't been listening to much live piano music, in the home or concert halls. And it ain't just the sub 30's either. JMHO of course. :-)