its a cool approach for sure. I tried to compare a 140L Super Planar example with a 140L Karlson, each with 15pzb40. The K is way too big for that driver punch-wise and loses against the Super Planar. If your hornresp fudge is good on the 115BK (and I think it may be ) then a 79L K does pretty well. (I've had vertigo and queasiness all day so even more prone to stupid mistakes than usual) 140L for a 1.2X 115BK is more suited to an 18".
https://i.imgur.com/y1oOoOM.jpg
https://i.imgur.com/y1oOoOM.jpg
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That is nice to hear, I have a couple of 18/21 SW115/DS115 laying around somewhere for prototyping projects for the winter times.
However on the first page the SW115 crossed through with a red line on the planar sub so I guessed it was not suitable, but now you're saying the DS has edge over the sw115 so does this mean the sw115 is workable in the planar design?
However on the first page the SW115 crossed through with a red line on the planar sub so I guessed it was not suitable, but now you're saying the DS has edge over the sw115 so does this mean the sw115 is workable in the planar design?
How motor force relates to our cabinet volume and tuning
USRFobiwan, Yessir, well .. it depends on the tuning in relation to cabinet size and motor force which can be said about any number of cabinet designs but the 8th order Super Planar variant is very demanding in this sense, I will explain:
The 18DS115 definitely has an edge over the SW115 in this 8th order style Super Planar because the additional motor force is called for (more than in the original 6th order Super Planar) in order to keep the cabinet size requirements reasonable with tunings down in the low 30s.................... However, If using an SW115 in this 8th order style cabinet and prefer to maintain our cabinet's internal volume of 600 liters then i would place the tuning into the mid 30s or ideally the upper 30s , which is just a matter of shortening the slender portion of the main path some .........
So both of those B&C 18" driver options are useful , it is just that the one with superior motor force can be used in a cabinet tuned lower, and the driver with less motor force should be in a cabinet tuned higher (if both cabinets are to be the same size and using the same sort of design)........
In the old original Super Planar 6th order subs seen in post #1 the 18SW115 had a red line through it only because the mounting depth of that driver prevented it from fitting into that particular cabinet with enough clearance for the driver's pole vent to breathe ........ We were limited on height because these cabinets needed to fit under a stage and there was only 23" vertical available , and width was also limited ............... Fortunately there was a heck of a lot of depth which we could utilize under the stage so we gladly took full advantage of it
, this being the reason why those cabinets ended up being that shape
The parameters of the 18SW115 are perfectly suitable for that Super Planar 6th order design (the 6th order is the less demanding variant , and in this "Club Sub" case they were tuned in the very low 30s) .... If those original cabinets were just a few inches taller then it means the drivers in our list with mounting depth that previously disqualified them would now have a chance to fit!........... Instead of our height and width being the same 23" we could trim off a few inches of width to be traded for a few inches of increased height and the internal volume remains basically the same
USRFobiwan, Yessir, well .. it depends on the tuning in relation to cabinet size and motor force which can be said about any number of cabinet designs but the 8th order Super Planar variant is very demanding in this sense, I will explain:
The 18DS115 definitely has an edge over the SW115 in this 8th order style Super Planar because the additional motor force is called for (more than in the original 6th order Super Planar) in order to keep the cabinet size requirements reasonable with tunings down in the low 30s.................... However, If using an SW115 in this 8th order style cabinet and prefer to maintain our cabinet's internal volume of 600 liters then i would place the tuning into the mid 30s or ideally the upper 30s , which is just a matter of shortening the slender portion of the main path some .........
So both of those B&C 18" driver options are useful , it is just that the one with superior motor force can be used in a cabinet tuned lower, and the driver with less motor force should be in a cabinet tuned higher (if both cabinets are to be the same size and using the same sort of design)........
In the old original Super Planar 6th order subs seen in post #1 the 18SW115 had a red line through it only because the mounting depth of that driver prevented it from fitting into that particular cabinet with enough clearance for the driver's pole vent to breathe ........ We were limited on height because these cabinets needed to fit under a stage and there was only 23" vertical available , and width was also limited ............... Fortunately there was a heck of a lot of depth which we could utilize under the stage so we gladly took full advantage of it
, this being the reason why those cabinets ended up being that shape The parameters of the 18SW115 are perfectly suitable for that Super Planar 6th order design (the 6th order is the less demanding variant , and in this "Club Sub" case they were tuned in the very low 30s) .... If those original cabinets were just a few inches taller then it means the drivers in our list with mounting depth that previously disqualified them would now have a chance to fit!........... Instead of our height and width being the same 23" we could trim off a few inches of width to be traded for a few inches of increased height and the internal volume remains basically the same
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That's right, there is a pattern =)
Freddi,
Sorry that you are not feeling well, get better soon Mister..... Our connoisseur and proponent of all things K-related must be healthy!
You have the right idea about these Super Planars, they can generate a lot of efficiency but require a much larger cabinet compared to Bass Reflex cabs or our old series-tuned designs like Karlsons , Karlflex, XKi , Karlsonator etc etc ......... That is the compromise .... I am finding that it becomes increasingly critical with lower tunings which insist upon a beefy motor to keep the cabinet requirements from becoming impractically large (especially the case with the 8th order variant) ....
Freddi,
Sorry that you are not feeling well, get better soon Mister..... Our connoisseur and proponent of all things K-related must be healthy!
You have the right idea about these Super Planars, they can generate a lot of efficiency but require a much larger cabinet compared to Bass Reflex cabs or our old series-tuned designs like Karlsons , Karlflex, XKi , Karlsonator etc etc ......... That is the compromise .... I am finding that it becomes increasingly critical with lower tunings which insist upon a beefy motor to keep the cabinet requirements from becoming impractically large (especially the case with the 8th order variant) ....
Pressure on the cone is a much more complicated story than just compression ratio. Any cabinet design that increases the efficiency of a cabinet is increasing the coupling between the air and the driver, which is going to generate higher cone pressures.
Right
Zettaairyouiki,
You make a very good point!
You are right ..
Hopefully someday soon David will unlock the pressure charts in Hornresp's OD mode so we can see what is going on there with pressures at the throat .... Currently the option is greyed out for me I suppose i could fire up Akabak if i am curious enough ...
Zettaairyouiki,
You make a very good point!
You are right .. Hopefully someday soon David will unlock the pressure charts in Hornresp's OD mode so we can see what is going on there with pressures at the throat .... Currently the option is greyed out for me
I suppose i could fire up Akabak if i am curious enough ...
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Nothing is locked, pressure is available for me in Od mode. I can't remember ever simulating anything where I was unable to check pressure.
Z's point is exactly what I was trying to tell the ROAR guy, incidentally. He's pretty confident that his design is great at high spl because of the low compression ratio but there's SO much more to it than that.
Z's point is exactly what I was trying to tell the ROAR guy, incidentally. He's pretty confident that his design is great at high spl because of the low compression ratio but there's SO much more to it than that.
I found it!
Ok , i guess i have been looking at the wrong thing .....
When i am at my acoustical power graph and then go to tools the "sound pressure" and "particle velocity" are both greyed out and unavailable to me .......
I think i just found the right one though (what you guys are referring to), i just needed to get the proper menu......From the diaphragm displacement page if i go to tools i see the "diaphragm pressure" and i do have access to that! .... So hmmm.... ok, AWESOME! .... I will post a screenshot from the 600 liter cabinet loaded with the B&C 18DS115
Ok , i guess i have been looking at the wrong thing .....
When i am at my acoustical power graph and then go to tools the "sound pressure" and "particle velocity" are both greyed out and unavailable to me .......
I think i just found the right one though (what you guys are referring to), i just needed to get the proper menu......From the diaphragm displacement page if i go to tools i see the "diaphragm pressure" and i do have access to that! .... So hmmm.... ok, AWESOME!
.... I will post a screenshot from the 600 liter cabinet loaded with the B&C 18DS115
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If you want to see those two items, from the acoustical power window go to tools - output. Then switch your output to either one side or the other (not combined). Then those two menu items should be available.
How were you living without velocity? Running everything through Akabak?
I think i just found the right one though (what you guys are referring to), i just needed to get the proper menu......From the diaphragm displacement page if i go to tools i see the "diaphragm pressure" and i do have access to that! .... So hmmm.... ok, AWESOME!
Yeah you found it. You can look at pressure on the front side of the cone, on the back side, or total pressure. It's a handy tool.
If you have issues like this just ask, don't just accept that the tool is not available to you. I've been following the Hornresp thread since the first post so I know where most stuff is. There's a bunch of stuff I don't use (and/or don't use yet) but I think I use most of the features. I don't care for bandpass so I haven't even looked in that section and I haven't attempted to sim a synergy yet but I will one day.
Diaphragm pressure
Just A Guy,
Excellent! Now they work .... Thank you for showing me how to gain access ....
Hehe, right, i had my roundabout ways if i needed them ..
I will, and thank you again Sir
Just A Guy,
Excellent! Now they work .... Thank you for showing me how to gain access
....Hehe, right, i had my roundabout ways if i needed them ..
I will, and thank you again Sir
It's the traditional 4th, 6th, 8th type bandpass I don't care for. I prefer stuff with a little flare flair.
That is true, the grater the loading the higher the pressure, which is key to efficiency, and no, it's not all about the compression ratio, but it never hurts to consider keeping it as low as possible given driver lifetime and in extreme cases even distortion.
What is of greater importance is how even you spread the forces on the cone, to me it seems pretty straight forward that a symmetrical dual path design will show a more even cone loading then a single path one, all else being equal, and the forces themselves are not dangerous unless you limit the excursion at the cost of proper cooling.
