I think David Weems has a lot to answer for, I bought "Designing, Building and testing your own speaker system" about 18 years ago, now I have speakers all over the place; not made from his plans, (I doubt you can still get the drivers, - piezo Reed tweeter?), but certainly using what I learned from the book. I used the "Crossover-network design chart" yesterday.
So cool how the box doubles as a tweeter stand. Surely the knowledgeable engineers designed the box to be optimum size to be antiresonant and the correct height to avoid floor bounce and couple via Allison effect, to let through the pure sound!
Now more seriously, what if you made this today with vastly improved magnetics and materials to focus on high frequency response and dispersion.
OMG, that book is how I became a loudspeaker design engineer! I learned enough to be dangerous, and intrigued by his multiple Audio Engineering Society references got an older friend to drive me to a university physics library, where I photocopied about a 9" stack of stuff and devoured it. There has been SO much progress and evolution in speaker design, and yet it is still in many ways a black art, emphasis on the ART of the design process.
I like a Wavecor without ferrofluid in 30mm.
And interesting the XT25 (also without ferrofluid I like a lot).
Both those tweeters seem to have similar high end dispersion.
But basically for tweeters I only seem to like the XT25 tweeter I think.
XT25 doesn't get annoying when going past quiet volumes.
Trying to decide between Peerless-TG9FD10-08 (or Peerless-TC9FD18-08) + SB Acoustics SB23CACS45-4
Or
2.5-way SB Acoustics SB15MFC30-8 5" Poly Cone Woofers + Peerless-XT25BG60-04
Or
Peerless-XT25BG60-04 + Dayton Audio RS52AN-8 + SB Acoustics SB23CACS45-4
Few different designs actually, too many choices.
One thing I noticed (especially if you don't like a lot of highs) is:
there aren't too many advantages over ScanSpeak Revelator 26W/8867T 10" Woofer Black Aluminum Cone +
SB Acoustics SB15MFC30-8 5" Poly Cone Woofers + Peerless-XT25BG60-04 (3-way)
or
ScanSpeak Revelator 26W/8867T 10" Woofer Black Aluminum Cone + Peerless-TG9FD10-08 (or Peerless-TC9FD18-08)
I mean for me, or seemingly. But I can listening to a 10" metal cone woofer by itself and be pretty happy.
Most of your excursion/compression/distortion issues with a wide variety of content will still be with the 10" 26W. Thermal, I don't know.
You should be able to get the Peerless-XT25BG60-04 + Dayton Audio RS52AN-8 to sound better than the TC9 by itself, but you have to cross it over 750 Hz instead of 400 Hz. And it has less Xmax and Sd.
But what was interesting the SB Acoustics SB15MFC30-8 sounds excellent also.
Basically most modern 2-ways suck.
Too many highs and no lows.
3.5" driver + 8-10" woofer is a way better 2-way than 1+6-7" 2-way.
My thinking is: If you can put a Sd 7 cm^2 tweeter and a 150 cm^2 woofer together; Sd ratio 21.42, you can definitely put a 36 cm^2 driver and 320 cm^2 woofer together; Sd ratio 8.89.
I'm not sure if people will like the Peerless-XT25BG60-04 + Dayton Audio RS52AN-8 (for example) better than the TC9 by itself, in blind tests.
There's a lot that can go wrong in the cross-over (I think) and Tymphany/Peerless drivers have some really nice performance figures.
So, yeah I would use a TC9/TG9 instead of a tweeter. Other fullrange drivers have strange FR issues (top end usually rising, but compensates for dispersion/beaming) if not EQed.
Also I think a lot of audiophiledom is just d00ds showing off; just what d00ds do I guess, with anything I suppose.
You hear that top end shimmer and/or clarity? No, I don't and I don't want to.
Why don't you impress me with the low end; WTF is at the top end? Nothing. All of physics/thermodynamics is in your favor reproducing high frequencies. Show me a speaker that has great bass in a box some one wants to look at and fits in a room and I'll be impressed.
Literally almost all the distortion you have in a speaker is in the bass. Or in the low end of a tweeter if it's a ribbon tweeter.
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I've given my whizzer coned 12" full range drivers a shot again, so far so good. They've never responded well to a crossover, and are down 3db on axis at 17500 hz by the specs and supplied graphs, but even slightly off axis I think it's more like 12000 hz.
They seem to be a pretty honest 97db efficient, and highpassing a HiVi RT2II set of 92db tweeters fills in the top end, while not adding floor bounce or ceiling reflections compared to a few dome tweeters I've tried,and even a 1 inch pair of AMT tweeters. Totally contrary to my understanding of what frequencies beaming occurs at, but welcome anyways. Less adding treble than adding completeness.
The 10" you reference has a lot of spiky breakup 4kHz - 10kHz.
My HF hearing is fading with age, but not enough to ignore something like this
I spent years trying to like wide band drivers, and gave up because they all had similar problems..
I liked a free pair of 4" speakers (salvaged from an old TV) more than the "full range" drivers that I paid money for. The response was uneven, but less spiky..
How old are you and what condition is your hearing in?
Not asking to be rude, but because I think there are genuine differences in what listeners with different ages & amounts of loss will appreciate.
Recent Munich HiFi Show had a few really good sounding system results, one of the better ones was from Rockport Audio with a nice Be tweeter.
However Davis Acoustics little cone (graphite coated paper with mini phase-plug) *tweeter sounded almost as good and the overall speaker build wasn't anywhere near as impressive as the Rockport speaker. (..this was a narrow baffle speaker, not their wide baffle design.)
*similar though smaller design to some non-fullrange "full"range drivers.
However Davis Acoustics little cone (graphite coated paper with mini phase-plug) *tweeter sounded almost as good and the overall speaker build wasn't anywhere near as impressive as the Rockport speaker. (..this was a narrow baffle speaker, not their wide baffle design.)
*similar though smaller design to some non-fullrange "full"range drivers.
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Basically a small dome tweeter
1" or even 3/4"
will always outperform anything larger Off axis.
No way around it cause the diaphragm or cone area.
dictates everything.
Nothing is gonna beat a metal dome.
And with any dome the usual surround
will be the area likely for
typical distortion around 2 or 3000 Hz.
So there's your magic.
If you can actually crossover a dome
3rd order or Higher at 4000 or 5000 Hz
you moving above typical distortion
from the surround at 2 or 3000 Hz
Hence why " fullrange" or " wide band"
Cone speakers 2" to 3" are incredible
more use full to move your dome tweeter
crossover much much higher.
Again hopefully 4k or higher
to stay away from distortion
of the dome surround around 2k or 3k
1" or even 3/4"
will always outperform anything larger Off axis.
No way around it cause the diaphragm or cone area.
dictates everything.
Nothing is gonna beat a metal dome.
And with any dome the usual surround
will be the area likely for
typical distortion around 2 or 3000 Hz.
So there's your magic.
If you can actually crossover a dome
3rd order or Higher at 4000 or 5000 Hz
you moving above typical distortion
from the surround at 2 or 3000 Hz
Hence why " fullrange" or " wide band"
Cone speakers 2" to 3" are incredible
more use full to move your dome tweeter
crossover much much higher.
Again hopefully 4k or higher
to stay away from distortion
of the dome surround around 2k or 3k
Don’t forget that some of these have ¾” dustcaps that act much like a small tweeter.
dave
Pretty Much. But not really.
Not to worried about off axis. it is a added benefit though.
More about sound quality and low distortion on axis
So basically nice Detail with no fatigue and clarity at high SPL
Hence metal dome , you wont beat for price or simplicity.
Long as its done right.
Going up higher off axis, just side benefit.
Not really the point. Sound Quality
I understand the points of hearing loss and age.
But if the system goes above hearing range losses.
Clarity and detail still better and noticeable.
I have no problem with highs on 2" or 3" paper cones.
think they are a little smoother sometimes.
It might part of it. People enjoy hearing 2k to 5k on
paper or poly more pleasing. Than hearing 2k or 5k on a dome.
again just need get past the surround distortion.
domes should be much higher.
and even with hearing losses the clarity and detail
is noticeable.
Not to worried about off axis. it is a added benefit though.
More about sound quality and low distortion on axis
So basically nice Detail with no fatigue and clarity at high SPL
Hence metal dome , you wont beat for price or simplicity.
Long as its done right.
Going up higher off axis, just side benefit.
Not really the point. Sound Quality
I understand the points of hearing loss and age.
But if the system goes above hearing range losses.
Clarity and detail still better and noticeable.
I have no problem with highs on 2" or 3" paper cones.
think they are a little smoother sometimes.
It might part of it. People enjoy hearing 2k to 5k on
paper or poly more pleasing. Than hearing 2k or 5k on a dome.
again just need get past the surround distortion.
domes should be much higher.
and even with hearing losses the clarity and detail
is noticeable.
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Sorry to bring this back from near dead…
The post got liked, and Allen B did a simulation of the lobing of a WAW with a 400 Hz XO, withing a quarter wavelength, a 4th order Linkwitz-Riley
This illustrates one of the evils of XOs gone.
Here is the lobimg seen in the moe common cone + dome (also complements of Allen)
dave
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Me too! And actually became a loudspeaker engineer. My mom: "I can't believe all that fooling around in the basement led to an engineering career!"
It took me many articles and a long time to understand what was oversimplified in his book but it was a great food-for-thought start.