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Does it? Lets just say hypotheticly you found a pair of large speakers that had nice solid cabinets and a simple driver arrangement an 8 inch woofer and a dome tweeter. And a mass loaded Passive radiator or any given size.
lets say you pull the woofer and you see that the magnet is small and it says:
Nominal 3W
8 ohms
XXX speaker brand
High efficiency
the tweeter has the same specs.
there is a very simple crossover.
And the speakers actually sound REALLY good.
The speaker is is hypothetical.
Follow Ups:
Sort of. Magnet size and strength are variables in speaker motor design but are no more or less important than voice coil design, gap dimensions, moving mass and mechanical properties of the suspension components and other metrics. Speaker motor design is truly a physics/engineering effort and often calls upon FEA (Finite Element Analysis) techniques to do correctly.
In any case, don't look at magnet size only but consider driver frequency response, distortion curves, polar response curvers, BL curves, power handling and excursion capabilities and other performance related metrics. Magnet size alone is not proof positive of superior quality or superior design. That said, larger motors cost more and typically designers don't put expensive components into shoddy designs. But there are some designs out there that boast large magnet size and not much more while some drivers with smaller magnets perform really well.
Just remember:
The best magnets do not ensure good motor design.
The best motor design does not ensure good speaker design.
The best speaker design does not mean you will personally like it.
Pick the speaker that sounds best of you and leave motor design considerations to the engineers and manufacturers.
Just a case in point, this driver:
http://www.madisound.com/pdf/vifa/mg10md09-08e.pdf
This (sadly discontinued) driver has a very small magnet yet is one of the flattest midrange speakers ever made. It's not good for very low frequencies, is not very efficient and can't handle loads of power, but with it's small magnet and small 3/4" voice coil and small fiberglass cone with special dust cap, this driver can be mated with practically any tweeter in existence, even those with higher resonant frequencies into the 1.5 - 2k range. I use four of these mids with "wee magnets" in a WMTMW design and they work really well, but within the above limitations. I truncated the frames and use "rectangle flange" tweeters for an absolute minimum center-of-tweeter to center-of-mid vertical distance, which needs to be even smaller as mid-to-tweeter crossover point goes up to avoid comb filtering.
Just remember that in the end nothing matters more than you being happy with the speaker. Not even "good measurements". Few people like a cheap, crappy, shrill and distorted sounding speaker. Most people generally like a speaker that is reasonably flat and low distortion that images well and give a sense of "realness" and palpability to the sound. But speakers meeting these criterion can have very different design philosophies and overall sound character and imaging.
Cheers,
Presto
Usage and context counts even more.
The size of the magnet influences the flux density or strength of the magnetic field and hence the potential amount of acceleration that can be imparted to the voice coil/diaphragm assembly. Larger magnets do provide the opportunity for increased overall efficiency but as others have suggested - it is but one factor in the total outcome. The well known damped harmonic oscillator equation provides cues as to what is going on:
d^2x/dt^2 + 2(damping coefficient)(resonant angular frequency)(dx/dt) +(angular frequency)^2(x) = 0
The first component represents the acceleration (force available to accelerate the moving mass of the coil/diaphragm). As one can see if this value is increased, the resonant frequency increases. Superimposed on this equation, in the case of an acoustic transducer, would be the cyclical acoustical loading of the diaphragm which varies essentially with the degree of acoustical coupling the diaphragm is capable of over a range of frequencies.
The bottom line of all of this is that larger magnets and stronger magnetic fields are potential improvements provided that the moving mass, suspension compliance, and damping of the system are properly balanced with the force applied by the combination of applied voltage and magnetic field to produce a loudspeaker that is neither overdamped nor underdamped. Additionally, as I noted in an earlier thread - more powerful voice coil gap field strengths reduce the amount of voice coil current needed to produce diaphragm deflection and thus reduce magnetic field fluctuations that cause distortion - particularly at higher frequencies.
...that the magnet ought to be the size/design/strength that best matches the purpose and function of the speaker?
One could even be so radical as to suggest that is also true of all the other parts.
It matters about as much as the size of an engine does.
This engine (built in 1915) weighs in at a bit over 3 tons and produces a maximum of 15 HP at 450 RPM. I prefer to see / hear it idling at about 90 RPM.
What matters to the loudspeaker driver is how strong the magnetic field is in the gap as well as how much volume that gap has that can be filled with VC.
Even then, the ideal amount is set by the low corner and box volume.
Looks like a hit and miss engine. If so, my 12 year old son and I are looking to find one (although smaller) at this very moment. We have 3 old Briggs, 1 Maytag and 4 old outboards on the bench at the moment. I encourage my son with this hobby because any pursuit is better than TV and Xbox. Thanks for the photo!
I want 1 the 1915 engine that is. I have some old tools it could run.
Hey, your the fellow up in Wisconsin aren't you (or i might be thinking of someone else).
If so, there is great place to go for this stuff. My kids and i go to this one and one in Illinois every year (a left over tradition from my Dad taking my brothers and i when we were little).
I love the sound of these old engines although the one in the picture (Fairbanks Morse Y)takes a gas blow torch and about 45 min to start.
The first time i got it running i scared the heck out of myself too.
Sound like you might have old machinery ?
Fun stuff
Best,
Tom
Only a 35 min drive from my home. Gone before probably attend again this year.
As we get closer let me know what day your going.
That is a very nice show, my dad had a favorite place under the trees at the end of the road through the kettle parade route.
Will do. Sure is a fun interesting event.
Hey were neighbors Kloss...im in Stevens Point
:)
"im in Stevens Point"
Isn't that where Point beer is made?
En so?
Been through there several times. Friendly chicks, too.
But Green Bay kicks your but* in football.
:)
Ya hey der
I only wondered since a lot of mid-fi speakers from some time ago seem to have small magnets and low wattages listed them (cabinet says otherwise) and they sound quite good and can hold thier own with other more recently made Mid-fi speakers. sometimes they sound a little better. Mine included.
Todays mid-fi speakers have larger magnets.
Depending on what your going to use the transducer for in general the more costly better made drivers have large magnets. Like with some amplifiers you can also tell a good bit about quality by weight but that being said I have 6-lb modern compression drivers that sound better than the 30-40lb ones lighter but higher gauss...... So as with most things audio YMMV.
how do hit and miss engines operate?
nt
This may be of interest.
Mount Pleasant Iowa old threshers reunion, Aug.30~Sept.3 2012.
That is a famous show, very large too.
It has always been a bit too far for a day trip although i would like to go there. There is another big one in Rolag Minnesota that i would like to go to someday.
Best,
Tom
Just as magnets can be too weak, they can also be too powerful.
It would be better to evaluate the Qts of the driver for its intended cabinet design (sealed, vented, etc).
those are simplistic specs and do not give you any thing,, what type magnet,,ferris,alnico or neo..and the strengths,,megnetic flux,,flux density..in maxwells and gauss Plus many more specs..
Maybe not so much with loudspeakers though.
*
...speaker builder Maria Muldaur said.
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