My tests found this to be accurate so far. i used hvac air filters to line 3 of the walls and measurements showed essentially no difference in areas of concern. maybe traditional egg crate open cell foam would be better. i think even closed cell foam might be best, but this is purely based off imagination. im guessing its not even be possible with a target frequency of 153hz. i think this is where metamaterial would have to be implemented. now it DOES still help to lower treble frequencies. I also found that orienting the cabinet to have the most acoustical boundary to give an improvement. i was surprised to see it didn't do much to improve the distortion figures. this may only be applicable in certain circumstances, ie direct radiators or when measuring at a distance.
purple is standing orientation no filters, green is standing orientation with filters, red is laying on side orientation with filters.
i agree with you. that's @ 20% xmax and 1200 watts. sundown u series can handle multiple thousands because of their renowned flatwound aluminum coils w/ black epoxy. ive yet to get these warm, even in full clip @ 2100watts. (i have a xls802 each channel going to a separate coil) right now the sundown uv1 15 on amazon for $350.
this picture shows more clearly why peq is better than a simple LP filter for HOQW designs. how else could you get this smooth of a rolloff? you would still have that nasty resonance. PEQ sounds SIGNIFICANTLY better. I was able to accomplish this with 10 adjustable bands and no LP filter. there is no gain at lower frequencies, its been spl aligned at 80hz. purple slope is 48db/octave @80hz.
Actually, for VLF in room, suspending heavy near wall size panels is the easy way, so suspended rigid foam panels might be the 'hot ticket'. For lined walls, suspend a thick blanket of whatever lines the walls. If required, fine tune by adding weight at the bottom.
treating the chamber like you would a room makes the most sense. adding mass loaded vinyl made a negligible difference. i was thinking metamaterial chambers but that's probably unnecessary. adding a grid of 1x with medium or low-density neoprene spanned across the top is probably much better. unfortunately, my port goes edge to edge so there is no room. ill have to think on it.
side note, applying the mass loaded vinyl again reminds me that the adhesive on all adhesive backed products is garbage. these companies need to start buying from 3m or something.
side note, applying the mass loaded vinyl again reminds me that the adhesive on all adhesive backed products is garbage. these companies need to start buying from 3m or something.
I gotta do this ! You nailed it, this is absolutely what these things need so nobody is stuck with that funk in a generic bw 24 slope, etc
thank you. i really enjoy the sound of it the more i integrate it. honestly it would sound better if i would just pull the whole thing down a little more. my little meh's are not that spl capable. they only have a 13$ soft dome. ive been thinking about building a budget paraline array for a while now. i haven't seen anyone diy one yet. on the other hand, i still want to put something in my truck. i just want something a little easier to take in and out. i found a twelve that has some serious capability. check this out....
12" subwoofer, 180L airspace...
2000 watt rms rating.
full xmax short term capability.
this is secret sauce material.
12" subwoofer, 180L airspace...
2000 watt rms rating.
full xmax short term capability.
this is secret sauce material.
I tried putting the TL —-> Helmholtz design into the tapped horn mode, so that separate resonators could be polyfil stuffed …
I’m screwing up something and it’s lowering the tuning ?
I don’t actually know what the first 37.5 cm of you sim is describing? The TL upstream of the driver (and the cone volume)?
I’m screwing up something and it’s lowering the tuning ?
I don’t actually know what the first 37.5 cm of you sim is describing? The TL upstream of the driver (and the cone volume)?
Attachments
Green is my crazy/dumb Hoqw box
Brown was the attempt at PEQ(copycat if you essentially)
Red is the 6th order parallel Helmholtz as reference, since it sounds so good but isn’t nearly as ‘loud’ with same drivers (-3dB as 8 ohm instead of 4 ohm in the hoqw)
Let me guess!!
BEYMA 12LEX1000FE ?
Ciare 12.00SW ?
Ciare CSW7112EVO ?
Faital 12HP1030 ?
Faital 12HP1060 ?
Faital 12RS1066 ?
Faital 12HP1030 ?
Faital 12RS1066 ?
B&C 12BG100 ?
B&C 12TBX100 ?
B&C 12FG100 ?
B&C 12NW100 ?
I would if you had one... I'll tell you that a q that low is going to have two extraordinary peaks...like 20db... And the frequency range in between will not only be mediocre, it will take 20,000 watts to get to 135db. Low q isn't ideal. Motorforce is great as long as it's coupled to incredibly stiff spiders. Spl woofers are ideal. Just not low q ones. The 12 I showed up top has a qts of .49, and the one I use is over .5!
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There is such this as an over-motored subwoofer. That dd is an incredible piece of craftsmanship, but I would send it back to dd and have them put proper spiders on it. And for that thing? 8 layer progressive roll would be great. Vas would probably 10, fs would be like 50hz and q would be in the ballpark. Oh yeah and someone would probably have to invent an adhesive to keep the coil attached to the spiders lol. As it sits though, its prolly only good for a ported box.... How boring! ðŸ˜
Chris Cooney has one of those. I couldn’t find anything in horn response to suggest/attempt other than a raging SPL spike (as you guys mentioned)
https://www.instagram.com/cscstang_customs?igsh=NTc4MTIwNjQ2YQ==
https://www.instagram.com/cscstang_customs?igsh=NTc4MTIwNjQ2YQ==