Klipsch K-402 another controlled directivity horn

[Bjorn]

Btw, I will probably audition the Danley SH50 any day now. That's another highly regarded horn construction. I've asked Bjørn for an audition of his system, but he's a busy man. But hopefully I'll be able to hear it in the not too distant future.

Old thread that I just came over. Hopefully I can demo the horn speaker system in 2021. At least in Bergen but probably other cities and when the time is ready also bring to an international hifi show. The focus lately has been on finishing amplifiers and a CBT speaker.

I had a pair of Klipsch K-402 for several years. They were sold quickly when we developed our own horn. The difference was bigger then I expected. Smoother, more relaxed, more natural sound with more energy in the highest frequencies. The off-axis measurement was improved. A large horn system with constant directivity is amazing IMO.

 

[Ro808]

Are those the final versions Bjørn?
The slots/throat adapters are still quite short, I presume (<8 cm length)?

 

[Bjorn]

Are those the final versions Bjørn?
The slots/throat adapters are still short, I presume (<8 cm length)?

Other than finish and aesthetics they are ready. I see no reason to change anything. They sound amazing. The slot/adapter is longer than that.

I do have another version you see below, but I don't plan to offer those anywere soon and they need a different midbass solution.

 

[Ro808]

Bi-Radial horn-tech anno 2020
The coverage angles of the last one appear to be smaller, or am I wrong?

 

[Bjorn]

Sort of but if we follow the true meaning of bi-radial, actually none of these are bi-radial horns. And so called JBL bi-radial horns were never really bi-radial either. It's a bit of a mess and wrong use of terminlogy. I do have a design for a true bi-radial horn by the way, but the size is likely to increase.

Coverage angels are the same for both those horns, 80x50°.

 

[Ro808]

With Bi-radial horns, I referred to the series of JBL horns that were produced under that trademark.

Those horns, as well as yours, were developed by the same legend, Don Keele.
Evidently, the profiles of these horns are not (bi-)radial in the mathematical sense.

 

[Bjorn]

Yes. JBL basically ended up using the bi-radial term of diffraction slot horns. Some were radial like the JBL 2360A and some were not. None of them had a bi-radial profile.

 

[hvbias]

Old thread that I just came over. Hopefully I can demo the horn speaker system in 2021. At least in Bergen but probably other cities and when the time is ready also bring to an international hifi show. The focus lately has been on finishing amplifiers and a CBT speaker.

I had a pair of Klipsch K-402 for several years. They were sold quickly when we developed our own horn. The difference was bigger then I expected. Smoother, more relaxed, more natural sound with more energy in the highest frequencies. The off-axis measurement was improved. A large horn system with constant directivity is amazing IMO.

View attachment 101793

How low do they control directivity to and what do you cross them over to below this horn?

 

[Bjorn]

How low do they control directivity to and what do you cross them over to below this horn?

They are constant horizontally to about 280 Hz, but doesn't change much before you get to around 150-100 Hz. Vertically they a constant to about 600-640 Hz and gradually gets wider.

To a midbass horn that matches and extends the directivity some, besides avoiding the floor bounce. While it certainly works well using a front firing woofer too, a midbass horn with the same directivity and lower distortion brings it to another level. A separate subwoofer solution is required with a crossover at 80 Hz or higher

 

[hvbias]

They are constant horizontally to about 280 Hz, but doesn't change much before you get to around 150-100 Hz. Vertically they a constant to about 600-640 Hz and gradually gets wider.

To a midbass horn that matches and extends the directivity some, besides avoiding the floor bounce. While it certainly works well using a front firing woofer too, a midbass horn with the same directivity and lower distortion brings it to another level. A separate subwoofer solution is required with a crossover at 80 Hz or higher
View attachment 173336

Very nice, what is the length and height of the total midbass plus mid/treble? I was planning to do something very similar with K402 in a dedicated listening room I'm building but am all for a superior integrated solution. Hopefully this pandemic will be more settled up by the time you're ready to bring this to market, I have friends outside of Stavanger. (High school foreign exchange programs are wonderful!)

For aesthetics reasons I'd prefer if both horns were the same length, ie some small false panels added to flares of the mid/treble horn.

 

[Bjorn]

Can't remember exactly but I think the length/depth of the midbass horn is around 122 cm. Total height approximately 169 cm.

 

[hvbias]

Can't remember exactly but I think the length/depth of the midbass horn is around 122 cm. Total height approximately 169 cm.

View attachment 173449

Looks great, will you be posting directivity measurements?

 

[Bjorn]

Looks great, will you be posting directivity measurements?

Yes, of course. However, not sure how the vertical will be presented since the midbass horn is designed to use the floor. One way is to measure the midrange and midbass horn separately and splice the measurements. Or simply measure both over a reflective floor.

You can get an idea about the horizontal in the meausurements below of the midrange horn vs. Klipsch K-402 apart from the fact the beamwidth is incorrect and much narrower.
Indoor measurement with no gating.

Klipsch K-402:

Our horn:

 

[dped90]

Looks great, will you be posting directivity measurements?

Great looking directivity plots of the K402. Would you know what size room that horn would typically be used in?

Might there be a next smaller version of this horn? And what would its Fc be?

 

[egellings]

insane...

You need two of those for stereo, right?

 

[sfogg]

Great looking directivity plots of the K402. Would you know what size room that horn would typically be used in?

Might there be a next smaller version of this horn? And what would its Fc be?

Smaller version of the K402 is the K510 which is a 500hz horn. I use them in my 2 way LCR LaScalas.

 

[Short38]

insane...

Padded room design. Gotta love the audacity!

 

[dped90]

Smaller version of the K402 is the K510 which is a 500hz horn. I use them in my 2 way LCR LaScalas.

Thanks for your reply. I've tried to find directivity charts on the K510 but no luck. Do you think they would resemble Troy Crowe's version of the A290 horn?

3D CAD plans for ES-290 Biradial Horn -- Horn No.1670

By purchasing these plans you'll automatically receive the 3D CAD files for the ES-290 Biradial Horn No.1670 via email. Zipped Folder Includes: .STL files for 3D Printing (Assembly and part files) .STEP, .iges, & .x_t files for CNC Machine CAM programming Does not include CNC programming...

josephcrowe.com

https://cdn.shopify.com/s/files/1/0142/2848/8292/files/Horn_No.1670_with_BMS_4591-8_off-axis3_480x480.png?v=1649504045

 

[sfogg]

Thanks for your reply. I've tried to find directivity charts on the K510 but no luck. Do you think they would resemble Troy Crowe's version of the A290 horn?

3D CAD plans for ES-290 Biradial Horn -- Horn No.1670

By purchasing these plans you'll automatically receive the 3D CAD files for the ES-290 Biradial Horn No.1670 via email. Zipped Folder Includes: .STL files for 3D Printing (Assembly and part files) .STEP, .iges, & .x_t files for CNC Machine CAM programming Does not include CNC programming...

josephcrowe.com

https://cdn.shopify.com/s/files/1/0142/2848/8292/files/Horn_No.1670_with_BMS_4591-8_off-axis3_480x480.png?v=1649504045

It won't go as low, it hits 500hz fine but drops from there. I've been running the K510s for about 18 years. I think Roy Delgado posted polars way back when on the Klipsch forum but I can't find them now. My K510s are actually prototypes I bought from Roy. There are knockoffs on ebay now for little money.

I posted much less sophisticated measurements on the K510 back in 2007 here. Measurements were made on a Spectral Dynamics SD380. Ignore the measurements on page 2, that was an interaction with a high impedance noise source.

 

[dped90]

It won't go as low, it hits 500hz fine but drops from there.

Thanks for a simple answer for a non-expert, which I might not get from Cask05 here.
https://www.diyaudio.com/community/...-can-reach-500-hz.321521/page-13#post-8022282

I'm still too much of a non-expert and no kind of diyer, as Troy will be using these clones of Gary Dahl's midwoofers to build some kind of a two or three way system for me. Meanwhile, I reasoned that a horn with a relatively low corner frequency to cross with my midwoofer would help keep it from beaming and keep it out of its higher distortion range. Please refer to Troy's measurements of them.

Would the ES290 horn be among the most appropriate to use, at least to get the Altec 416-8B midwoofers to perform within their best limits?

However, when I asked the same thing of Cask05 is he saying here that almost any horn with excellent off axis response at 900Hz will work, though some better than others?

Smallest Footprint Horn and Driver that can reach 500 Hz

www.diyaudio.com

But what does he mean by single sided and non-single side horns? What are the differences? Are single sided horns mostly round horns, like JMLC horns https://azurahorn.com/azurahorn_horns.html and/or the round kind of Tractrix horns? https://horns-diy.pl/horns/tractrix/tractrix-350/

But in any case, why might single-sided horns be preferable, or just as appropriate to use with my midwoofers, as non-single sided horns?

Of course, I will ask Cask05 about all of this, hoping for answers that I can understand. Thanks.