I appreciate this. I am still not ready to give up on the ported design. I knew this all would be challenging, that is why I am doing it. I suppose I am a glutton for punishment.
I did change the crossover point quite a bit. It has mostly eliminated the hump. The mid will play down to 400 just fine. It rolls of so it needs to be bumped up to play accurately. Here is the newer XO I am working on. Ignore the dips in room response at the XO points. I knew this would be an issue but it is meant to listen to very closely and on axis so I get to ignore this. At least I get a break somewhere on this build.
My very first 3 way had such a long port it ended up being a transmission line as well. I stuffed the crap out of it will polyfill and it magically worked out. I needed some bass boost to get back the bass but it sounds great. I could fill this and see what happens.
Alternatively, I could make the port much narrower. I could make it a smaller, round tube. It is only this size to avoid chuffing at very high volumes. Volumes where it will likely almost never play. I could flare the port way more if it was narrower, this may resolve the chuffing all on its own. I believe this to be the next step after trying to fill the port.
I have considered this as well. Getting a hold of quality, real, acoustic felt is a challenge. Do you know of a place in the USA to procure it?
Oh yeah, lol. I forgot I cannot L-pad before the filter. Good catch. I always try to do that though.....
Ok, so if I shorten the port I can move out the resonance beyond my crossover point.
I can either
A) Leave the port the same cross section and lose some low end by only shortening the port. It won't hit down nearly as low as I want but it also won't make my mids sound like trash
B) Cut down a bit of my cross section and shorten the port. This also fixes my resonance issue BUT I could potentially have some chuffing at the full 60W.
For those of you who do not know, the red in hornresp is after changing the port length and area. The black line is before. This program is scary accurate. I only started using this a couple months ago when I playing with front loaded horns.
Both of these options should fix the resonance issue. I suppose I can print out a couple of different ports, add a big fat flare to the smaller cross sectioned one, and see what happens. The multispool holder on the printer is still broken so I cannot print anything huge but I can still print normal sized things.
I can either
A) Leave the port the same cross section and lose some low end by only shortening the port. It won't hit down nearly as low as I want but it also won't make my mids sound like trash
B) Cut down a bit of my cross section and shorten the port. This also fixes my resonance issue BUT I could potentially have some chuffing at the full 60W.
For those of you who do not know, the red in hornresp is after changing the port length and area. The black line is before. This program is scary accurate. I only started using this a couple months ago when I playing with front loaded horns.
Both of these options should fix the resonance issue. I suppose I can print out a couple of different ports, add a big fat flare to the smaller cross sectioned one, and see what happens. The multispool holder on the printer is still broken so I cannot print anything huge but I can still print normal sized things.
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Since your x-over is external. a big x-over will fit. 😛
This could be of interest. It might not work, but I give it better odds than my previous suggestion. Offsets are likely off a bit. I usually find that the shape of the roll-off tells me a lot. The phase on this sim looked terrible. I really wonder about that. Maybe this will be of some help anyway.
This could be of interest. It might not work, but I give it better odds than my previous suggestion. Offsets are likely off a bit. I usually find that the shape of the roll-off tells me a lot. The phase on this sim looked terrible. I really wonder about that. Maybe this will be of some help anyway.
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Alright, here's what I am right now.
I have created this port. It should push the resonance towards 600 hz. That is far enough above where I plan to cross to my mid.
Horn resp accurately predicated the previous 340hz resonance peak with the old port so I don't see why it wouldn't do the exact same for this port.
And yes, I do see that it will just fall over if I try to make it exactly this. I will make it viable as a stand somehow. Just haven't finished it up.
I have created this port. It should push the resonance towards 600 hz. That is far enough above where I plan to cross to my mid.
Horn resp accurately predicated the previous 340hz resonance peak with the old port so I don't see why it wouldn't do the exact same for this port.
And yes, I do see that it will just fall over if I try to make it exactly this. I will make it viable as a stand somehow. Just haven't finished it up.
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New port data is in! Thanks for everyone's help. I am going to consider this issue solved.
Hornresp is awesome.
I have learned that anytime I design a port I should run a sim in Hornresp to check out the resonances.
I shortened the port and make the square area smaller. Modelling this in hornresp pushed out the resonance past 500. The sim was within 30 hz. Pretty cool. Definitely made by people much smarter than I. This port looks a lot cooler as well.
All I need to do now is tame this frustrating planar mid then polish up this XO and I'm good to go. On to the next couple of week of fiddling around.
Hornresp is awesome.
I have learned that anytime I design a port I should run a sim in Hornresp to check out the resonances.
I shortened the port and make the square area smaller. Modelling this in hornresp pushed out the resonance past 500. The sim was within 30 hz. Pretty cool. Definitely made by people much smarter than I. This port looks a lot cooler as well.
All I need to do now is tame this frustrating planar mid then polish up this XO and I'm good to go. On to the next couple of week of fiddling around.
