To say light cones are better or heavy cones are better is like saying stiffer springs are better for a car. It depends on what size car they go in, and what type of ride is desired. That's my opinion. What are your thoughts?

What I was trying to suggest is that the impression that a driver with a particular cone, heavy or light, is "better" may be related not to the moving mass but the inherent stiffness of the cone material or geometry - does that make any sense?

As for tuning, high mass diaphragms have low free air resonance. An example would be something like a 12" or 15" car subwoofer tuned to 20Hz or so. Low mass diaphragms have higher free air resonance. Examples would be 12" and 15" drivers with free air resonance around 40Hz and up.

One school of thought is to use a high-mass diaphragm in a basshorn with a very small rear chamber to shift resonance up. Another school of thought is to use a lighter cone and to have a larger rear chamber or open back.

I've made horns of both types, but some people say one is "right" and the other is "wrong." Bill Fitzmaurice, for example, regularly instructs people that high-mass/low-resonance drivers are wrong for basshorns. Tom Danley preaches the exact opposite. So I thought I'd open a thread for discussion.

Personally, I think it depends what one wants from a basshorn. If purely used for subwoofer duty, the high-mass/high-excursion driver is probably a better choice. If used up through the midbass, I'd use a driver with a lighter cone. I'd also fold the horn differently for the two different types, with the subhorn having folds that attenuate higher frequencies but the midbass horn either being straight or having folds that acted as reflectors, directing higher frequencies towards the mouth.

Do I interpret your words as comparing similar diameter cones on a beam balance - some impregnated pulp and goop covered cones will be heavier than some thin poly cones for the same diameter? If so, can that necessarily dictate Fs? With the same surround, the same suspension, the same voice coil and former you can expect the mass to determine the Fs, but it doesn't necessarily follow, does it? The heavier cone could just as well be supported by a stiffer suspension and surround making it a higher Fs driver than the lighter cone, no?

It seems to me there has to be a far more complex relationship for there to be a preference; that many other physical parameters have to be considered in addition to mass alone including the combined +/-kX aspect.

Greets!

Not necessarily:

Fs = [(1/Pi)/2]*{[1000/(Mms*Cms)]^0.5}

where:

Mms is in grams and Cms is in m/N
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>To say light cones are better or heavy cones are better is like saying stiffer springs are better for a car. It depends on what size car they go in, and what type of ride is desired. That's my opinion.
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Yep, it all depends on the desired BW and acoustic power/watt you want. If I only need it to load 30-100 Hz, why force a 40 Hz Fs driver with a 400 Hz HF mass corner to do it?

GM

Higher mass results in a lower resonant frequency if suspension stiffness is the same. That was sort of an implication, but maybe I should have been specific.