And Now For Something REALLY BIG

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btw, there's nice new 8" from 18sound...8MB500
though Im not sure it sounds any better than Beta8
or may even be worse
all you may get for sure is better build quality, and probably a tougher driver
old 8MB400 is on sale at Lean and looks like a bargain, if its any good
measurements look different, but that could rely on many other things, and not mean anything, hard to say really
 
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...... like it can handle 2khz just fine and would push more air

be careful with measurements
may not sound like it looks :D
bigger drivers are usually not very good above 1khz, but ofcourse depends
but you really have to know the driver well to rely on anything above that
and many drivers(most) will probably fail long before that
but again, playing loud, the smaller driver may fall first
 
Oh great

The great and mystical Baffle Step Correction

How does that work on these very wide speakers? Wide is good right? (gets hit by wife :D)

The ideal situation is to have a speaker large enough, that baffle-step is around the point where room gain kicks in. Speaker placement versus the floor, side and back walls allows for some "fine-tuning" with regards to this.

I just finished building large speakers of my own, 22" wide and 37" tall. Baffle step should be around 200Hz, but I don't feel like I need any correction with them in my 10'x13' room. Alternatively, since you want a ~200Hz Xover, it might land pretty near the baffle-step point and all that will be needed is to adjust driver levels accordingly, if at allnecessary.

IG
 
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Incorrect- breakup is much more closely tied to stiffness- which decreases with increasing driver diameter assuming constant cone thickness.
In a strict mechanical engineering sense of the term, yes.

With speakers, "breakup" is used more loosely. Guitar players use it to refer to harmonic distortion (mostly caused by exceeding Xmax), what you're referring to they call "cone cry".

In hifi, it's most often used to refer to the notchy hash above the wavelength/diameter limit, much of which is the comb filtering that causes beaming.

Real cone breakup tends to generate a high resonant spike, and can most often be seen in tweeters and fullrange drivers.
 
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Now this is an interesting thread. A few years ago I built a pair of Iwata horns designed for a 2" driver. Up until now I haven't found a suitable bass cabinet to accomodate these horns. The main idea was/is to keep it a two-way system. Suggestions are welcome. As you can see in the picture they serve as a printer stand and collect dust ;)

Regards

This is basically what you have the start of. Best speaker I've ever heard. Build a 6cu ft box and use either the TAD 1601 15" woofer or the Lambda TD15X woofer. Then use either a TAD 4001 CD on the horn or a JBL 24xx CD with the True Extent barrilium (sp) diaphragm.

For me, best 2 way you can find.

http://www.youtube.com/watch?v=S11nqJmqYKs

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He is the evolution on my old room. Then a pix of the new reduced system in my new room.

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In a strict mechanical engineering sense of the term, yes.

With speakers, "breakup" is used more loosely. Guitar players use it to refer to harmonic distortion (mostly caused by exceeding Xmax), what you're referring to they call "cone cry".

In hifi, it's most often used to refer to the notchy hash above the wavelength/diameter limit, much of which is the comb filtering that causes beaming.

Real cone breakup tends to generate a high resonant spike, and can most often be seen in tweeters and fullrange drivers.

The notchy hash doesn't take place with metal cones, until the failure of the material stiffness. The off-axis falls off cleanly. The off-axis misbehavior in softer coned speakers is due to damped breakup.

Speaker Building Supplies from Madisound

In Hifi we're talking about breakup, not only high-Q breakups, but any breakup in the mechanical sense. Guitar speaker talk definitely is more loosely defined, but their light floppy cones tend to "break up" mechanically much more easily than hifi cone assemblies.
 
The notchy hash doesn't take place with metal cones, until the failure of the material stiffness. The off-axis falls off cleanly. The off-axis misbehavior in softer coned speakers is due to damped breakup.
Speaker Building Supplies from Madisound
Huh? That thing hits 2K then BAM! Don't let the smoothing fool you.

But that's what I'm saying, really - the "breakup" is caused by acoustic realities, not mechanical limits. Most folks aren't driving their hifi speakers to where 'cone cry' is an issue.

Then again, given the subject of this thread, it might be a consideration.
 
That 2k is where the material stiffness fails. Look at breakup in compression drivers if you need more proof- it tracks material as well as size. The cone ceases to be a piston when it breaks up, thus along with any peaking, whether damped or not, the off-axis has variation. Note that in the 10" the beamwidth narrows BEFORE any breakup, it's a smooth rolloff until breakup.
 
The notchy hash doesn't take place with metal cones, until the failure of the material stiffness.

The cone ceases to be a piston when it breaks up

thanks for the info badman. I'll be using paper for the bass & mid. How does one tell without being able to measure the driver yourself, that it wont breakup within a certain bandwidth?
 
thanks for the info badman. I'll be using paper for the bass & mid. How does one tell without being able to measure the driver yourself, that it wont breakup within a certain bandwidth?

Well, breakup isn't inherently evil. Like with instrument speakers, some "hifi" speakers are operated well through breakout range, like the Audio Nirvanas. They're known to sound quite great, and you can see wiggles in their impedance traces (and FRs) that point to these, though they're relatively modest.

Most pro speakers will have their datasheets show the peaking and breakup behavior pretty obviously. 15"s it's usually 1kHz-1.2kHz, 12"s more like 1.5-1.8kHz, 8"s at 2k-2k5, etc.
 
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The cone ceases to be a piston when it breaks up.....

or it just lost its built in flex control mechanism, or inner damping
I believe only the really heavy coned subwoofer drivers have real pistonic behaviour

btw, it looks to me like quite many of the new pro woofer designs have severe breakup peak
probably due to stiffer cones
but I guess pro people dont care so much about a small peak, and like the stiff cone more
 
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