It does baffle me how much the WG shape does to lower cutoff frequencies. Some smaller tractrix horns you'd never think of going that low based on mouth diameter and depth, but I realize the ripple can increase drastically with shorter horn depths. Many smaller 1" WGs look like they defy laws of physics ie. Faital STH100 (I'm shocked at how low this WG goes for its size).
Autotech make to order from Poland
If your interested in the K402 a simpler dual flare conical of the same size would have only a bit worse performance.
Being in my early 50s, I can still hear up to about 15k and I'm quite happy with the HF extension I get from Seas T35C-002 35mm domes. I can however hear the more open sound of a good 25mm metal dome up top. Many of the smaller 1" compression drivers don't really do well past 13k or so despite having response past 15k on paper. The reason I mention all this is most larger CDs don't sound good past 7k or so. In my case with the DCX50, the midrange portion of this driver has an open sound on its own only going up to 9k, so this driver does something different than most 2" CDs I've heard. The cone design probably has something to do with it. Either way, if I needed a super tweeter with this coax driver and not use the HF element, I'd be ok with it. The Celestion driver in the Klipsch Jubilee doesn't sound as open as the mid portion of the DCX50 alone on a smaller horn. Maybe that has alot to do with the horn itself rather than the driver.
@kipman725 - I was thinking the same thing. The compromise simplifying the WG design may be not as severe, but I'd hate to waste the time and energy finding out otherwise. I'd be happier with the looks of a Yuichi clone (so would my wife), but there's something to be said about saving over a grand and doing a simplified build of a K401 WG.
Some K402 directivity plots here: https://www.audiosciencereview.com/...other-controlled-directivity-horn.1120/page-4
K401 looks to be a 1" throat exponential flare?
K401 looks to be a 1" throat exponential flare?
Thanks for posting that link. Very interesting and clarifying. You're right about the part numbers. I got thrm mixed up.
I usually shy away from horns with diffraction slots, mainly because most tend to color the top end and cause distortion at higher levels. When i say higher levels, most people would just not care thinking it would be a non issue listening at lower levels. The problem can show up with HF transients at fairly low levels, but being the person I am liking dynamics, I've heard some nasty stuff from hirns some people claim to sound decent at lower levels. I come from the world of planars and electrostats, wanting more dynamic range but still have the fine resolving stuff underneath. Its hard to have your cake and eat it too. It doesn't qualify as accurate if it doesn't pass my piano and vocal tests.
Most large horns suck at HF dispersion, which is understandable from the physics point of view. That doesn't mean it can't be done.
I usually shy away from horns with diffraction slots, mainly because most tend to color the top end and cause distortion at higher levels. When i say higher levels, most people would just not care thinking it would be a non issue listening at lower levels. The problem can show up with HF transients at fairly low levels, but being the person I am liking dynamics, I've heard some nasty stuff from hirns some people claim to sound decent at lower levels. I come from the world of planars and electrostats, wanting more dynamic range but still have the fine resolving stuff underneath. Its hard to have your cake and eat it too. It doesn't qualify as accurate if it doesn't pass my piano and vocal tests.
Most large horns suck at HF dispersion, which is understandable from the physics point of view. That doesn't mean it can't be done.
not ASFIK. The classic JBL big bum horns sound OK to me but I couldn't live with them at home as I find the midrange a bit weird like someone is speaking through cupped hands. Some comparative measurments with the K402 here: https://data-bass.ipbhost.com/topic/1381-measurements-from-big-cds-and-horns/
I've got my heart set on a pair of these A290 Yuichi clones from Athos. Unless something else significant catches my eye, these will likely be the best option for me while keeping my wife happy concerning looks. She normally doesn't say much about my speakers, but I'd rather keep her happy than push my luck further, as she did approve the money I plan on spending on this build. We'll see what else comes along.
That's significant info. I'd say JBL got it right with the 2445 back when they were more modern. The K402 doesn't look all that great compared to the 2360.
Yes, I'm aware of the huge 2360 beung an absolute monstrosity. My wife would never go for that in our living room as accepting as she is with my hobby.
The K402 is much friendlier looking, but still not as liveable as the A290 clone I'm considering. The all wood construction makes it the most attractive looking horn, plus the performance is great with a larger driver.
I already talked with Athos about my specs and will likely pull the trigger on a pair of his A290 clones as pictured above.
The K402 is much friendlier looking, but still not as liveable as the A290 clone I'm considering. The all wood construction makes it the most attractive looking horn, plus the performance is great with a larger driver.
I already talked with Athos about my specs and will likely pull the trigger on a pair of his A290 clones as pictured above.
I think Diggy was actually suggesting you reach out to me. The Athos is an excellent clone of the A-290, quality is very high. I have the standard A-290, not the FL (which has no vanes)
A good approximation of CD EQ will be required whether you do that actively or passively, above the driver mass rolloff you need boost @ 6dB/oct. I am also using EQ below the mass roll off - works well.
This is not the horn for a small room. My room is too small at 3.25m wide and 5.8m long, ceiling height is just over 2m. (basement lab and man cave.)
I have spent a lot of time learning about room treatment as this horn lights up most of the surfaces in the room. Interestingly there are no polar plots of this horn that I have been able to find online. Initial measurements indicate it is probably over 100° in the horizontal plane, I have no verticals, but I will guess between 60 - 70° based on in room behavior. These are not reliable numbers as I don't really have a clue what I am doing quite yet.
If you have a room at least as large as mine and preferably larger the horn can be made to work, the larger the room the better it will likely work IMLE.
I have 9 acoustimac absorbers on the walls in here, a couple behind the speakers, several on the walls just forward of them, and others in various points the room. I have 4 bass traps and various things to diffuse sound, the room itself is rather full of stuff. I am just about to start treating the ceiling in specific areas.
It now sounds better than the 2380A without room treatment, but only just, and it's been quite a lot of work. Further improvements are coming and I am happy with the current result and will likely find other room improvements pay off.
I think it would be a good idea to stay away from the FL unless you have a much larger room than mine.
Thanks for letting me know all this. I was planning on the standard A290s with vanes. I wanted better directivity and HF control, so I figured it was smarter to stick with the original design.
My room is quite wide @ 17 ft and almost 30 ft long with 14 ft vaulted ceilings. I don't have much reflective surface near the speaker locations. I can get away with wide dispersion. Thats why I wanted larger horns to fill the room better and have more even coverage in the whole space.
The low end from the current 12" SB acoustics subs is great but lacking some of that upper bass punch you can only.get from large pro sound drivers, therefore I'm going with B&C 18PZB100s in large aperiodic ported cabs run from Ice-Power plate amps. The rest will be active analog xover biamped with a Parasound JC5. Midbass drivers are B&C 12MH32 in small FLH running 100 to 500 hz passive xover to DCX50s in A290 horns.
If I need a super tweeter, I'd likely use my 18sound NSD1095Ns on STH100 WGs to start and go from there. I like the 18sound drivers for their clear hifi like HF, similar to a really good dome tweeter. Thats the best way I could describe that driver on that WG. Hopefully the DCX50 will work ok in coax mode and I won't need an extra HF driver.
I was originally going with 8PE21s for mids, but didn't like the idea of needing extra midbass to make up for little xmax of the 8PE21s. The 12MH32 is my current favorite midbass driver. It sound so clean and immediate from 100 - 1000 and takes well to horn loading. It can play blisteringly loud in a small cab with little power and very low distortion. I've tried the 12PE32 as well, but it doesn't have the weight in the lower mids as.the 12MH32, likely due to the slightly lighter and more flimsy cone. It also handles less power before compressing.
My room is quite wide @ 17 ft and almost 30 ft long with 14 ft vaulted ceilings. I don't have much reflective surface near the speaker locations. I can get away with wide dispersion. Thats why I wanted larger horns to fill the room better and have more even coverage in the whole space.
The low end from the current 12" SB acoustics subs is great but lacking some of that upper bass punch you can only.get from large pro sound drivers, therefore I'm going with B&C 18PZB100s in large aperiodic ported cabs run from Ice-Power plate amps. The rest will be active analog xover biamped with a Parasound JC5. Midbass drivers are B&C 12MH32 in small FLH running 100 to 500 hz passive xover to DCX50s in A290 horns.
If I need a super tweeter, I'd likely use my 18sound NSD1095Ns on STH100 WGs to start and go from there. I like the 18sound drivers for their clear hifi like HF, similar to a really good dome tweeter. Thats the best way I could describe that driver on that WG. Hopefully the DCX50 will work ok in coax mode and I won't need an extra HF driver.
I was originally going with 8PE21s for mids, but didn't like the idea of needing extra midbass to make up for little xmax of the 8PE21s. The 12MH32 is my current favorite midbass driver. It sound so clean and immediate from 100 - 1000 and takes well to horn loading. It can play blisteringly loud in a small cab with little power and very low distortion. I've tried the 12PE32 as well, but it doesn't have the weight in the lower mids as.the 12MH32, likely due to the slightly lighter and more flimsy cone. It also handles less power before compressing.
@kevinkr - how do the vanes change the horizontal and vertical behavior of a horn like the A290 compared to no vanes at all? I thought the vanes were acting as a phase plug of sorts and helping/modifying vertical wavefront expansion? I would think not having vanes would hurt both horizontal and vertical dispersion.
I made an attempt using the original Yuichi plans to create a hornresp simulation of the vertical beamwidth. (measured data would always be preferrable)
Wow, it really takes off under 1k. I see now why this horn can be a challenge to use in a smaller setting. Luckily my ceiling is high and textured, so I have an advantage. That can also be corrected with the appropriate crossover slope, plus steering the overlap lobe down with an offset LP slope to delay the LF. Of course that sim may be off as well, so I may be the first to measure beamwidth for this horn. Thanks for the research!
No problem. I look forward to your measurements.
Pattern flip and DI variations with frequency can't be changed with a crossover, but they can be compensated. Your readiness to manage your ceiling shows you are prepared.
Have you seen my thread on non-axisymmetric waveguides? - https://www.diyaudio.com/community/...on-axisymmetric-waveguide.375799/post-6754095
Pattern flip and DI variations with frequency can't be changed with a crossover, but they can be compensated. Your readiness to manage your ceiling shows you are prepared.
Have you seen my thread on non-axisymmetric waveguides? - https://www.diyaudio.com/community/...on-axisymmetric-waveguide.375799/post-6754095
Yes, I saw that thread a while back. As I said before, the loss of pattern control vertically can be steered by the xover away from the ceiling to some degree in the overlapping xover region.
You can use the phase response of the driver you're crossing with to your advantage by creating an asymmetrical radiating lobe down to the neighboring driver with the inherent delay on that driver. It requires that driver to have extended response an octave or so above its intended xover for best results, otherwise the narrowing dispersion will allow the WG with its widening vert pattern to prevail and some amount of linearity in power response will be lost. That scenario above creates a "mouthy" sounding system off axis and even on-axis if the room is very live in that range (which most will be).
An MTM driver arrangement can be beneficial if a vertically loose WG is used in a room with low ceilings. That requires the WG xover to start rolling off with a stepped / mixed slope to compensate relative phase + amplitude, reducing off axis WG redation through the phase cancelation when the cone drivers + WG combine in the overlapping region. Delaying the HF further narrows the vertical dispersion around the region the drivers share response, but it only works if the driver spacing is less than 1/2 wavelength of the highest frequency in the overlapping xover region (preferably 1/4 WL). Combing can take over if this isn't managed carefully and you also loose potentially precious lower octave output from the CD, so its not that practical if the driver has limited low end response to start with using lower xover frequencies. That doesn't leave alot of wiggle room with driver or crossover selection and isn't so practical with driver combinations most people would use. It can however work wonders if you've tried and failed with other approaches and room treatment isn't pratical.
Using a larger MTM 2 way system to achieve this method of pattern manipulation would require very linear smaller duameter cone drivers with shallow cones that have wider off axis behavior. Its sort of counter productive when designing a system from scratch,.mainly because you could have selected the proper WG to start with.
I realize this approach isn't going to be practical most of the time, but even on a simple large 2 way system it can improve audio quality in compromised situations if you have comprehensive control over your xover parameters ie with DSP. Steering the combining lobe away from reflective surfaces can be the only (and easiest) thing in your power to change under these circumstances. It does require some time and patience to get it right along with a bit of math if you want to speed up the process. This is mainly a pro sound type of solution, but it could be implemented in a hifi setting as well if done carefully, to eek out the last bit of performance.
You can use the phase response of the driver you're crossing with to your advantage by creating an asymmetrical radiating lobe down to the neighboring driver with the inherent delay on that driver. It requires that driver to have extended response an octave or so above its intended xover for best results, otherwise the narrowing dispersion will allow the WG with its widening vert pattern to prevail and some amount of linearity in power response will be lost. That scenario above creates a "mouthy" sounding system off axis and even on-axis if the room is very live in that range (which most will be).
An MTM driver arrangement can be beneficial if a vertically loose WG is used in a room with low ceilings. That requires the WG xover to start rolling off with a stepped / mixed slope to compensate relative phase + amplitude, reducing off axis WG redation through the phase cancelation when the cone drivers + WG combine in the overlapping region. Delaying the HF further narrows the vertical dispersion around the region the drivers share response, but it only works if the driver spacing is less than 1/2 wavelength of the highest frequency in the overlapping xover region (preferably 1/4 WL). Combing can take over if this isn't managed carefully and you also loose potentially precious lower octave output from the CD, so its not that practical if the driver has limited low end response to start with using lower xover frequencies. That doesn't leave alot of wiggle room with driver or crossover selection and isn't so practical with driver combinations most people would use. It can however work wonders if you've tried and failed with other approaches and room treatment isn't pratical.
Using a larger MTM 2 way system to achieve this method of pattern manipulation would require very linear smaller duameter cone drivers with shallow cones that have wider off axis behavior. Its sort of counter productive when designing a system from scratch,.mainly because you could have selected the proper WG to start with.
I realize this approach isn't going to be practical most of the time, but even on a simple large 2 way system it can improve audio quality in compromised situations if you have comprehensive control over your xover parameters ie with DSP. Steering the combining lobe away from reflective surfaces can be the only (and easiest) thing in your power to change under these circumstances. It does require some time and patience to get it right along with a bit of math if you want to speed up the process. This is mainly a pro sound type of solution, but it could be implemented in a hifi setting as well if done carefully, to eek out the last bit of performance.