Optimal Driver Selection for First-Order Crossover Systems

Tweeterz should have ferrofluid.
The other type of speakers, equipped with double suspension, don't suffer much the out-of-band excitation.
Metal cones have the 'zing' and other materials have their attributes.
The speakers should play distinctly and all together, each playing the same voice
diyAudio Member
Joined 2007
Have a look at Duntech/Dunlavey designs to see how a 4-Way First order speaker is done, and as above.
It's not as easy as it might seem, especially as most of the drivers I would recommend haven't been made for 20 years or more or I have no experience with a lot of the new offerings. Vifa P11 and M-11 come to mind, Vifa M-22 and P-21 perhaps and the venerable Vifa D27 silk dome tweeters now sold by ScanSpeak.
Some work with Zobels is often needed to get a first order XO to work
Baffle step and woofer top end response
are main contributors.
And hard to work around with 1st order

Ideal woofer roll off not be too bright or rising response.

Otherwise to overcome the problem.
Lower crossover for woofer or side mounted woofer.

"Skinny" magical baffles will cause a bigger baffle step.
Main way around that and have a skinny baffle
is a taller tower.
Can be narrow to " look" magical.
But the tall tower creates a larger baffle for better response.

One good simple example is a Woofer assisted Wideband (WAW)
done by Visaton Stella Light
Side mounted woofer naturally rolls off high-end
and tall tower helps improve baffles step

Pretty impressive response for 1st order
Great impedance curve as well.
Even a tuber could love that flatter impedance curve
and not usually so smooth with 1st order


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My two cents: woofer, midbass, midrange, tweeter -- that's a really ambitious 4-way target, to find sonically compatible drivers that are based on similar membrane material/characteristics (necessary because the overlap is large). But 2-way (say woofer/midrange) often exists within a product line, say 8" and 5", and 3-way (less tweeter) may be quite doable from one company catalog. That leaves midrange/tweeter 1st-order, which is an often-solved problem with some known combinations. One example is Monitor Audio Studio series, all Al/AlMg 1st-order 2-way except the flagship 60 being 3-way (but midrange allowed to run without HPF). My first diy 2-way paired fiberglass honeycomb with AMT (series 1st-order), a proven combination used in Eve Audio monitors (spun off from Adam). To go 3-way simply add a bigger honeycomb. My third example would be Fostex (say alnico line or eΣ as much as possible) 12" widerange, 8" fullrange, 4 or 5" fullrange, then a (super)tweeter. Fourth example, Mark Audio AlMg fullrange(s) in the middle, Al cone woofer, AlMg tweeter (like the Monitor Audio gold dome, second-hand). Last example, SB Satori TeXtreme.

Given their sonic compatibility, and each driver having a wide frequency range, the rest can be optimistically attempted!
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Anything past a 2 way with 1st order
is waste of time.

It can sound ok
plenty of 80's and 90's speakers
with 1st order 3 ways sounded fine.

Modern day with software aid
and measuring equipment.
Heck just sim from FRD.

Not even necessary to do 1st order.
It is by no means " easier"
and by far not " magical"
with less blah blah blah in the signal path.

your just susceptible to more cancellation off axis
and not very flat response by any mean.
Way more possible things with even basic 2nd order.
and much more control of the impedance curve.

Again the series crossover shown above
with side mount woofer solves alot of problems
not having to hunt for magical woofers and ideal
responses to get a first order to work.
tweeter distortion as a whole , is a big pass
on 1st order
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diyAudio Member
Joined 2007
I did build a speaker box with three drivers and only three passive component.
An offshoot of the Reference 2-way thread
But I was //
A: Lucky
B: Working with drivers well known to be very smooth
C: Very lucky

A 2.5 way using a Vifa P13 unfiltered in an overlarge enclosure for a Q of 0.55 a huge inductor on the woofer and a cap and resistor on the Vifa D27-45-06
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