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Klipsch K-402 another controlled directivity horn

And does Cask05 mean that any horn which can reproduce 900Hz with wide dispersion (no audible beaming?) will work, though some better than others and/or with other unrelated performance advantages?
 
I have no direct experience with the ES290 so this is just going by what I can see in the measurements. It should easily go low enough for your Altec's, it likely goes considerably lower than needed too. I cross my Lascala's over at 500hz which is a 15" woofer in a folded horn.

What he is talking about on the higher end is if the horn/driver frequency response will narrow on the top end, essentially if they will start to beam too. Some horns do, some don't. There is a bit of a trade off either way. If it keeps coverage consistent all the way up (often called a CD horn or constant dispersion) you have even coverage over all the horns range but on the flip side need an EQ boost up top. If the horn narrows you typically don't need an EQ boost on the horn but your coverage won't be as consistent.


Looking at the ES290 polars you see that it is narrowing as you get higher up.

Wether you want that or not is up to you. If you have a single listening position that isn't a huge deal (though the power response in room will impact what you hear) or if you have enough distance between the speakers and your seats so that you get the coverage you need for all seats. You can also cross to a tweeter before the mid narrows too much but then there is added complexity of a crossover and the interactions between drivers there.

I originally had my Lascala stock and then went through a number of horns on them as I wanted to try and get rid of some of the colorations of the original horn in it and I also wanted to better integrate the drivers.

First was Altec 511Bs with 902 with the lighter diaphrams they offered running two way. I crossed them at 600hz using 'extreme slope' crossovers which was a speaker level elliptic crossover. These were in a longer room so more distance from the speaker and the collapsing coverage wasn't a problem. When I moved them into my theater the angles got wider and the drop off on the high end was noticeable in some seats.

I ended up trying some Altec 805B multi-cell horns with 288-8G drivers. I dropped my crossover down to 500hz with those. I ended up using DSP to build elliptic crossovers for these too as I wanted as little overlap/interaction between horns as possible. Those were interesting horns, they were built to try and increase dispersion. They handled the low end well but up top each cell basically narrows and you get this sort of fingering between cells where the high end comes and goes as you move around. I ended up crossing them over to JBL 2404H at 6 or 8k. The 805B had some horn coloration in them too.

I decided I wanted to get back to the simplicity of a two way which meant I would need a horn that could get down to 500hz but that would also have the coverage I need for all seats. Which meant I would need a CD type horn. Would have loved the K402 but they physically wouldn't fit in my system. Then I heard about the K510 and bought Roy's prototypes. They load down to 500hz fine, have a tractrix flare (less colorations) and have constant dispersion up top. I cross them over with an elliptic at 500hz. Been running those for a long time.
 
And does Cask05 mean that any horn which can reproduce 900Hz with wide dispersion (no audible beaming?) will work, though some better than others and/or with other unrelated performance advantages?
He is looking at the 15" woofer and basically picking a place where you could try and match the power response of the woofer (which has begun to beam) to the power response of a horn. Speakers interact with the room and if at all possible you don't want a widely different power response between two drivers, esp. at a crossover point.

There are other considerations too of course. That is assuming the Altec is good to 900hz and beyond really depending upon your crossover slopes and probably also only running 1 woofer.

The other unrelated performance advantages would be things beyond the polar response of the horn at the crossover point. Dispersion up top, diffraction/colorations, pattern and even physical size in if it fits your system or not.
 
2" exit is really old school. Higher third order distortion compared to 1.5" or 1.4" exit.
 
Are you talking about the non-linear distortion that can occur at higher SPL levels more typical of sound reinforcement? JBL testing for that was at 107db.

FWIW, my drivers are 1.6" exit.
 
Are you talking about the non-linear distortion that can occur at higher SPL levels more typical of sound reinforcement? JBL testing for that was at 107db.

FWIW, my drivers are 1.6" exit.
Sorry for a late reply.

Well, yes and no. 107 dB was the level at 10 kHz. It was lower at lower frequencies. The measurement was at 1 meter distance, and thus the level will drop with you typical listening distance. Thirdly, distortion was high with 2" exit. For example above 3% with 97-98 dB/1m at approximately 6000 Hz. With a listening distance at 3 m, the level has fallen to 88-89 dB. So distortion is likely fairly high with a little lower level as well.

It's also generally easier to remain the beamwidth higher in frequencies with a smaller exit.
 
FWIW, my drivers are 1.6" exit.
Yes, the K402 is also too big for my room and even to sit upon my midwoofer cabinets safely. But why did Klipsch apparently discontinue the K510 horn? Cask05 referred me to this knock off. https://community.klipsch.com/topic...-510-horn-anyone-try-yet/#findComment-2466408 But as it's presumably not geometrically identical to your genuine K510 how likely would it have even more colorations or HOM resonances? https://www.ebay.com/itm/233808725468

However, if these original horns have been available for much over a decade it seems strange that Klipsch hasn't developed a horn to replace the K510.

Did the throat exit of your (Altec 288-8G ?) drivers require adapters for the K510 horn?
 
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Well, yes and no. 107 dB was the level at 10 kHz. It was lower at lower frequencies. The measurement was at 1 meter distance, and thus the level will drop with you typical listening distance. Thirdly, distortion was high with 2" exit. For example above 3% with 97-98 dB/1m at approximately 6000 Hz. With a listening distance at 3 m, the level has fallen to 88-89 dB. So distortion is likely fairly high with a little lower level as well.

It's also generally easier to remain the beamwidth higher in frequencies with a smaller exit.

If the 1.4" Radian 745neoBe is a poor man's TAD beryllium, what is it about its design that would negatively impact the sound in a two-way system, assuming the (passive) EQ was perfected to flatten and extend the HF response? https://www.usspeaker.com/radian 745neoBepb-1.htm
 
If the 1.4" Radian 745neoBe is a poor man's TAD beryllium, what is it about its design that would negatively impact the sound in a two-way system, assuming the (passive) EQ was perfected to flatten and extend the HF response? https://www.usspeaker.com/radian 745neoBepb-1.htm
Too small voice coil, leading to a higher crossover which is never a good thing.

It's a 4" voice coil you want to use and choose a constant directivity horn that can be crossed comfortable at 600 Hz or lower. And it needs to be an active design for high quality. Passive is a no go.
 
Too small voice coil, leading to a higher crossover which is never a good thing.

It's a 4" voice coil you want to use and choose a constant directivity horn that can be crossed comfortable at 600 Hz or lower. And it needs to be an active design for high quality. Passive is a no go.
I think Pierre crossed those Radians in the Athos TH4001 horns with his TAD woofers between ~ 725 and 775Hz. https://www.diyaudio.com/community/...horns-measurements.395046/page-3#post-7253984

It all seemed to work for him well in the end.

But later on Pierre did mention this "midrange aberration" which he to live with. Though they were designed by an expert
https://sphericalhorns.net/2023/10/...ic-loading-optimized-fc-300hz-horn/#more-2741 ,might that sonic artifact be due to the need to use throat adapters to mate the 1.4" Radians to the 2" TH4001 horns?

Perhaps no such problem if Pierre had these 2" drivers? https://www.usspeaker.com/radian 760neoBepb-1.htm
 
Yes, the K402 is also too big for my room and even to sit upon my midwoofer cabinets safely. But why did Klipsch apparently discontinue the K510 horn? Cask05 referred me to this knock off. https://community.klipsch.com/topic...-510-horn-anyone-try-yet/#findComment-2466408 But as it's presumably not geometrically identical to your genuine K510 how likely would it have even more colorations or HOM resonances? https://www.ebay.com/itm/233808725468

However, if these original horns have been available for much over a decade it seems strange that Klipsch hasn't developed a horn to replace the K510.

Did the throat exit of your (Altec 288-8G ?) drivers require adapters for the K510 horn?
I think Klipsch has a slightly different version of the K510 now that has what they are calling mumps. Not sure on availability of it. The ebay horn is supposed to be good. I think I saw a few posts from people that compared it to an original K510 and didn't see/hear a difference. Certainly low cost.

I don't run the 288s on the K510. I use the Peavey 44xt which are 4" titanium diaphragm drivers rated to 500hz second order. I biamp my Lascala bass horns at 500hz with elliptic crossovers.
 
Sorry for a late reply.

Well, yes and no. 107 dB was the level at 10 kHz. It was lower at lower frequencies. The measurement was at 1 meter distance, and thus the level will drop with you typical listening distance. Thirdly, distortion was high with 2" exit. For example above 3% with 97-98 dB/1m at approximately 6000 Hz. With a listening distance at 3 m, the level has fallen to 88-89 dB. So distortion is likely fairly high with a little lower level as well.

It's also generally easier to remain the beamwidth higher in frequencies with a smaller exit

Per the specs of the driver I am using, at 110db at 1khz the third harmonic is down about 55dB. That is 0.18% distortion. At 500hz it is down about 50dB or 0.32%.
 
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