Hi.
Just curious - I currently have two sets of speakers, a pair of old Mission M66i, and a pair of B&W 601. The Missions have domed tweeter cones in a very soft pliable material, and the B&Ws have metal cones, much less domed.
How can they be so different?!
I'd have thought that the firmer material of the B&Ws would project the higher frequencies better, but the Mission tweets work just fine too. How can such a soft material project so well? Why are their designs sooo different?
Thanks for any insight 🙂
Just curious - I currently have two sets of speakers, a pair of old Mission M66i, and a pair of B&W 601. The Missions have domed tweeter cones in a very soft pliable material, and the B&Ws have metal cones, much less domed.
How can they be so different?!
I'd have thought that the firmer material of the B&Ws would project the higher frequencies better, but the Mission tweets work just fine too. How can such a soft material project so well? Why are their designs sooo different?
Thanks for any insight 🙂
Broadly there are two approaches with cone materials: hard and soft.
Hard materials are stiff and retain their shape throughout the frequency passband but above the passband they tend to resonate strongly. Working with hard cones requires careful attention to motor design so that the harmonics don't drive the resonances to audible levels and to the crossovers which need to be relatively steep (not always desirable depending on other factors) and possibly include notches complicating the crossover design. Tweeters are a bit more tolerant of having their resonances driven because the frequencies tend to be above the range of audibility.
Soft materials are less stiff and tend to bend and resonate at the high frequency end of the passband. To handle this soft cones tend to include high levels of damping so that the resonances have a small magnitude. Working with soft cones tends to be significantly easier than hard cones, they tend to have a wider usable passband, can be used with shallower crossover slopes, don't require notches in the crossover, the bending at higher frequencies changes the radiation pattern which can sometimes be beneficial.
I have no doubt missed a few relevant points (e.g. hard cones and phase shields) but the gist is both approaches can work with soft cones tending to have the edge with 1 or 2 way speakers, hard cones having the edge with 4 ways and 3 ways being debatable.
Hard materials are stiff and retain their shape throughout the frequency passband but above the passband they tend to resonate strongly. Working with hard cones requires careful attention to motor design so that the harmonics don't drive the resonances to audible levels and to the crossovers which need to be relatively steep (not always desirable depending on other factors) and possibly include notches complicating the crossover design. Tweeters are a bit more tolerant of having their resonances driven because the frequencies tend to be above the range of audibility.
Soft materials are less stiff and tend to bend and resonate at the high frequency end of the passband. To handle this soft cones tend to include high levels of damping so that the resonances have a small magnitude. Working with soft cones tends to be significantly easier than hard cones, they tend to have a wider usable passband, can be used with shallower crossover slopes, don't require notches in the crossover, the bending at higher frequencies changes the radiation pattern which can sometimes be beneficial.
I have no doubt missed a few relevant points (e.g. hard cones and phase shields) but the gist is both approaches can work with soft cones tending to have the edge with 1 or 2 way speakers, hard cones having the edge with 4 ways and 3 ways being debatable.
What you can believe to hear in the tweets mainly comes from what is before : the mid, its low pass and tweeter high pass.
Metal dome of this BW is said to be good, it has a big deep iirc in the 8K to 10 K hz vinicity iirc which is often related to a nice sounding in some listening tests. (brigtness is often in the 6k to 8K Hz aera)
Som fabric are sounding less softer than some aluminium. Some fabrics also can be very harsh.
Metal dome of this BW is said to be good, it has a big deep iirc in the 8K to 10 K hz vinicity iirc which is often related to a nice sounding in some listening tests. (brigtness is often in the 6k to 8K Hz aera)
Som fabric are sounding less softer than some aluminium. Some fabrics also can be very harsh.
I always thought the shape of a ‘dome’ tweeter was more interesting than the material. You have hemispherical, flattened, hyperbolic, reverse or concave, and bell shaped Allison tweeters.
I have several pioneer HPM material outstanding cone mid and tweeter
Silk done dynaudio , excellent
Paper cone very good
Beryllium done , rings a little harsh
Silk done dynaudio , excellent
Paper cone very good
Beryllium done , rings a little harsh