40hz ratings/speaker response

I have recently read an article that stated that even if a certain low frequency fundamental tone is not reproduced by the speaker, if 2 or more higher harmonics of that fundamental are heard, the brain will psychoacoustically hear the fundamental tone. I have not actually verified this by testing, but it seems interesting. It may actually be the reason that some accurate mini-monitors seem to produce more bass than they should theoretically be capable of. It is common that mini speaker owners seem to be quite satisfied with the bass response of their speakers that are rated only down to 100Hz or even higher. Naturally, room loading and other factors may play into this. Anyone else heard about this phenomenon?

Twl:
www.melhuish.org/audio/article3.htm if you haven't already seen it.

Clueless, thanks, that was where I read it. I just couldn't remember where it was. Also, I noticed he was pretty rough on quarter wave pipes in that article. But, if you really tear any design apart that far, then nothing will really hold up too well to that kind of scrutiny. I'm still thinking that I can get a "happy medium" of decent bass-boost, and limited notch-effects from comb-filtering, from the Voigt Pipes. He didn't even mention the "baffle-step" effect of the Voigt Pipes, where the narrow baffle reinforces the higher freq's and you get a drop-off where the baffle is no longer wide enough to reinforce the lower ones. I've got a couple of tricks up my sleeve to handle this, without resorting to a compensation circuit that destroys efficiency.

Joeb, the point that I was trying to make was that sound waves can't be heard if they don't have room to develop at least one full cycle. For simplicity sake, one cycle of sound meanders like the letter S. According to the laws of physics, one full cycle of sound at 40 cycles per second needs 28 feet to develop. That is why I thought 40 cps was the lower limit for a normal listening room. One would have to be rich to have a room large enough to hear deeper tones. However, Bob at inpepinnovations said that only one half of the space required for a full cycle is required in order to hear a low frequency. One half of a full cycle would look like the letter C instead of the letter S. Assuming that the revised theory is correct, 40 cycles per second (hertz) could be heard in a 14 foot room, not a 28 foot room as I first proposed. Also, sound at 25 hertz would only require a 23 foot room, not a 45 foot room. In short, my theory was shot down.

Allow me to propose an anology to explain the limitation of the 40 hertz rated speaker. Imagine a soprano singer trying to sing bass. The vocal cords are too short to develop the lower frequencies, and thus distortion sets in. As you proposed, let's imagine that the soprano singer tries to sing bass even louder on the second try. The distortion would be louder and more pronounced, but the lower octave would never be reached. If the soprano singer continues these attempts, her vocal cords would be destroyed, just as a speaker would be destroyed in the same attempt.

Hi Twl:

Was just going through this site as I saw your post back here. You might enjoy??? ("God-awful" voigt pipe from the club of Norway", he says) it if you haven't already been there. I'm not sure what to make of it. I'm messing around with a few of the same Qs you are it seems.

www.geocities.com/rbrines1/index.htm

Cheers,
Ryder