Hi!
Been looking a bit into building a high efficiency two-way with a 1st order filter. In other words, as simple as possible.
Are there any good HE drivers out there that works well with a 1st order filter?
I see Zu Audio are doing it with a 10" wideband/full-range.
Maybe a Dayton PM220 wideband woofer with a Dayton AMTPRO-4 or something?
Any suggestions? 🙂
Been looking a bit into building a high efficiency two-way with a 1st order filter. In other words, as simple as possible.
Are there any good HE drivers out there that works well with a 1st order filter?
I see Zu Audio are doing it with a 10" wideband/full-range.
Maybe a Dayton PM220 wideband woofer with a Dayton AMTPRO-4 or something?
Any suggestions? 🙂
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That is a really tall order, especially if you want it to sound good. Your proposed drivers will definitely not result in good sound. For one thing, the AMTPRO has a rapidly falling response above 10k, so unless you are partially deaf you will notice that.
A first order filter rolls off very slowly. You will not be able to use a "tweeter" and likely not a CD+horn either, because you won't be able to attenuate the signal enough before resonance. It might be possible to use a very large horn with a 2" CD that can go down to 500Hz or so, and then cross it over to a high output 10" around 1.5kHz, but I suspect this is not what you are after.
So you are left using two high efficiency wideband drivers. I would choose a 6" to 10" high SPL fullranger with whizzer cone and a 12" pro audio woofer, and cross around 800Hz.
Keep in mind making the crossover more and more "simple" at some point has some diminishing returns. How will you account for baffle step, or other FR irregularities? Why not just build a good high SPL fullranger and have a sub kick in at 150Hz, or whereever the fullranger low end starts to roll off. You get a crossover for free in that case...
A first order filter rolls off very slowly. You will not be able to use a "tweeter" and likely not a CD+horn either, because you won't be able to attenuate the signal enough before resonance. It might be possible to use a very large horn with a 2" CD that can go down to 500Hz or so, and then cross it over to a high output 10" around 1.5kHz, but I suspect this is not what you are after.
So you are left using two high efficiency wideband drivers. I would choose a 6" to 10" high SPL fullranger with whizzer cone and a 12" pro audio woofer, and cross around 800Hz.
Keep in mind making the crossover more and more "simple" at some point has some diminishing returns. How will you account for baffle step, or other FR irregularities? Why not just build a good high SPL fullranger and have a sub kick in at 150Hz, or whereever the fullranger low end starts to roll off. You get a crossover for free in that case...
Can't hear anything above 13k so not an issue of me.
Zu Audio crosses a 2" inch Radian 950 electrically at 7 khz or something. What the actual acoustic XO point ends up being is another story. But that's what I'm interested in exploring.
Yeah, baffle step would need to be handled somehow. Some FR irregularities are just fine. Excessive FR irregularities equals bad driver choice in my opinion.
Ignoring the issue of baffle-step for a minute. Why not go for a widebander and a 1st order tweeter with a high XO instead of a fullranger?
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1st order 2 way
This is such an alluring concept at first, but VERY difficult to pull off correctly. There have been many articles and attempts since the beginning of the dynamic speaker.
Three (minimum) conditions must be met. The woofer and tweeter must have a minimum 2 octaves of flat overlap at the intended crossover frequency in the frequency domain. Three is better. Both drivers must exhibit very smooth natural roll off characteristics at both ends of their operating range in the frequency domain and both need to be aligned in the vertical plane in terms of the operating acoustic center(s).
Both will very likely require Zobel parallel circuits and or resonance damping circuits to be able to yield flat impedance and frequency response. And that is just the beginning!
Not saying it can't be done... but once you meet the above criteria you may be surprised at how small you woofer and how large your tweeter (HF) driver need to be. Also, as soon as you add any series crossover components you will likely end up with 2nd order (or even higher) acoustic slopes where you do not necessarily want them frequency wise.
This is such an alluring concept at first, but VERY difficult to pull off correctly. There have been many articles and attempts since the beginning of the dynamic speaker.
Three (minimum) conditions must be met. The woofer and tweeter must have a minimum 2 octaves of flat overlap at the intended crossover frequency in the frequency domain. Three is better. Both drivers must exhibit very smooth natural roll off characteristics at both ends of their operating range in the frequency domain and both need to be aligned in the vertical plane in terms of the operating acoustic center(s).
Both will very likely require Zobel parallel circuits and or resonance damping circuits to be able to yield flat impedance and frequency response. And that is just the beginning!
Not saying it can't be done... but once you meet the above criteria you may be surprised at how small you woofer and how large your tweeter (HF) driver need to be. Also, as soon as you add any series crossover components you will likely end up with 2nd order (or even higher) acoustic slopes where you do not necessarily want them frequency wise.
I heard Zu many times at audio shows and never liked the sound. They measure poorly and sound equally bad. Not enough bottom end, lumpy shouty upper end.
but they look cool.
as does oma, i wonder if oma measures as bad as they seem to measure?
Thanks for valuable feedback! It seems my impression that a 1st order speaker was a whole lot easier than higher order ones was quite wrong...
Thing is, I've tried a lot of two-way speaker combinations using an active filter, and never got them to sound "right". Thought a 1st order passive with the right drivers would be hard to f**k up 🙄
That Vifa C20WH one looks amazing! Shame you cannot get that driver anywhere.. I wonder if there is any good alternative driver?
Not what I would call high efficiency 🙂 Although the 10F is an amazing driver! Maybe just do an array of those...
I've actually used that woofer before. Excellent driver! But not high efficiency (per my definition).
one could make a Druid (or whatever) style cabinet with Eminence's current B102 plus a Morel Cat 37-8 dome with only a 5.6uF cap as the crossover. It would be moderate in efficiency. Box/pipe volume would probably best be somewhat larger than the Druid and around 1.7 - 2 cubic feet
Diuid sized pipe with only lining and old spec Eminence B102 - it would be somewhat smoother with light fill
comparison of the orignal low Qts B102 to the present model:
Diuid sized pipe with only lining and old spec Eminence B102 - it would be somewhat smoother with light fill
comparison of the orignal low Qts B102 to the present model:
First-order filters are difficult. The drivers need a wide range where they can overlap and maintain power handling, avoid peaks in the frequency response, etc.
You can get something reasonable with a Faital Pro 10HX230 and a single component for each driver, although power handling is limited and the phase curves don't line up fantastically.
I found better results by going to 2nd order filters - more power handling, and better frequency response.
Sensitivity came in at about 97dB@1w.
Chris
You can get something reasonable with a Faital Pro 10HX230 and a single component for each driver, although power handling is limited and the phase curves don't line up fantastically.
I found better results by going to 2nd order filters - more power handling, and better frequency response.
Sensitivity came in at about 97dB@1w.
Chris
If you listen at what I consider moderate levels, with 5.6uF a Morel CAT378's dome can be seen moving
42 liter pipe w. B102 - a bit bigger wouldn't hurt - don't forget to think about the amp output impedance
a classic Dynaco A25/A40XL in good shape would be nice
42 liter pipe w. B102 - a bit bigger wouldn't hurt - don't forget to think about the amp output impedance
a classic Dynaco A25/A40XL in good shape would be nice
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Defo, ever considered good coaxial? Tannoy, or something cheaper, B&C...plenty coaxials to choose from. Pro speakers typically have higher efficiency.
If you have deep pockets the Beyma pro coaxials, as identified by @adason, may do the job.
LOUDSPEAKER 12CXA400Fe 8 OH
This is a 12” which you can buy a pre built crossover (12db slope, 2nd order) for. Data sheet shows combined response with the crossover
LOUDSPEAKER 12CXA400Fe 8 OH
This is a 12” which you can buy a pre built crossover (12db slope, 2nd order) for. Data sheet shows combined response with the crossover
-baffle-step loss is going to kill your eff. with that combo. 😱
Yeah, a suggestion:
18Sound | ND1480A
XT1464
The Raptor ... a 10" MTM
and at about 20" wide with a volume around 3 cubic feet (sealed):
15W500
Target filter should be similar to the Spica TC 60 (though an octave lower):
Spica TC-60 loudspeaker Measurements | Stereophile.com
-probably a box-on-stand aesthetic similar to TonyG's (though not vented), and with a bit of backward "tilt" to aim the midbass to the listener, perhaps more like the Avantgarde Zero (but without the tweeter):
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that's a cool 18Sound woofer - a 450uF series cap (assuming low impedance drive) should make it go flat- lower. I'm not sure of the impact that might have on sound quality.
Very interesting to see the differences between the old one and the new here!
You mean buy and forget, or pulling some drivers from it?
Very nice curve with the cap on that Morel! How does it compare to the Seas DXT I wonder?
I've been looking at the DIY Sound Group Volt 10 coax. Seems pretty nice for the money, and I get a free lunch with a finished crossover.
Those Faital coaxials look quite nice tho. Even if the curves are quite smoothed and low resolution. Couldn't find any unofficial measurements of them.
Are there any finished projects / crossovers for one of these coaxes anywhere I wonder? Preferably one that includes BSC.
Too large a system for me unfortunately 🙂
I was actually thinking of building a TV-bench with integrated speakers on each side. Something like this:
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Have you seen the pispeakers?
http://www.pispeakers.com/Prices.html
One,two and two towers have very simple filters
http://www.pispeakers.com/Prices.html
One,two and two towers have very simple filters