One more thing, can a brace go over a driver tap inside S1-S2? Such as this
Are you sure the driver won't slap that brace at high excursion? Xdamage for your drivers is 21 mm. That's cutting it pretty close if it gets played with the hpf set wrong or off. Now is the time to be sure.
Yeah I did think about that and for a second though "whoops!"
But, the material thickness is 31mm so the driver is dead anyway by the time it would reach the brace, still have 10mm extra
But, the material thickness is 31mm so the driver is dead anyway by the time it would reach the brace, still have 10mm extra
I have no idea where I got 31mm from.
I'm going to cut some space out of the brace above the drivers... 10mm or so. My material thickness is only 19mm (31, what??) so to be on the safe side I will give it some more clearance- there is indeed an overlap. Good catch and thank you!
I didn't make as much progress as I'd hoped today, I think the 5am worknight last night kinda took it out of me... and I cut a few S2+ braces that didn't come out quite right due to measuring error... I decided to turn in for the night after that and come back with fresh eyes tomorrow. The past hour or so I have mainly been looking at midbass horns, and the tractrix is more and more appealing- especially if I could somehow get 100hz out of it with just one driver. I couldn't get the referenced tractrix spreadsheet to work for me very well, need to keep messing with it I suppose.
After everything is all said and done I'll be adding the braces into the design build sheet. Is that what you guys call a "csa"?
I'm going to cut some space out of the brace above the drivers... 10mm or so. My material thickness is only 19mm (31, what??) so to be on the safe side I will give it some more clearance- there is indeed an overlap. Good catch and thank you!
I didn't make as much progress as I'd hoped today, I think the 5am worknight last night kinda took it out of me... and I cut a few S2+ braces that didn't come out quite right due to measuring error... I decided to turn in for the night after that and come back with fresh eyes tomorrow. The past hour or so I have mainly been looking at midbass horns, and the tractrix is more and more appealing- especially if I could somehow get 100hz out of it with just one driver. I couldn't get the referenced tractrix spreadsheet to work for me very well, need to keep messing with it I suppose.
After everything is all said and done I'll be adding the braces into the design build sheet. Is that what you guys call a "csa"?
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Let me run a sim for you with the tractrix design I have all drawn up already and scaled to your maximal dimensions of 39 in wide mouth. You are set on using the 8FE200 though right? It probably won't reach 100Hz in the sim, but what I have noticed is that the bass may actually go deeper than predicted. If sims pan out, just use the 2d cut templates I made.
You're the best! Yeah I have two 8FE200s. Does your template need to have a certain mouth aspect ratio? Because if at all possible I would love to keep it to 11" height, but it's not a deal breaker- I could simply scale up if necessary. Looking forward to seeing what the sim looks like!
Thanks again 😀
Thanks again 😀
The tractrix horn is designed as a 1.5 wide to 1 high aspect ratio. Which makes it 19.5in high. You don't want to to go too flat of an aspect as that may give bad dispersion and would require me to completely redo the CAD plans and that won't be possible as it is too much work. My initial sims show that this can work if you are willing to take a -10dB EQ high shelf to trim the sensitivity down to 100dB from 110dB at 100Hz, 1m/2.83v. This is what I have to do to get the sensitivity of the tractrix to match my bass as well. It is an EQ negative boost (cut) so it reduces excursion and harmonic distortion as well.
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Hi jennygirl,
As to bracing across the driver port, here is a picture by Josh Ricci on a DTS-10 modification. Relieve the area where the surround/cone could possibly hit, and orient the brace in the direction of the flow not accross it. The DTS-10 thread has a lot of great build pictures in it.
Danley DTS-10 "Super Spud" DIY kit - AVS Forum
Cleats can be square or triangular, I'm not a great believer in corner deflectors, they just loose you volume, but they do strengthen the box and may provide places for grips and casters.
Regards,
As to bracing across the driver port, here is a picture by Josh Ricci on a DTS-10 modification. Relieve the area where the surround/cone could possibly hit, and orient the brace in the direction of the flow not accross it. The DTS-10 thread has a lot of great build pictures in it.
Danley DTS-10 "Super Spud" DIY kit - AVS Forum
Cleats can be square or triangular, I'm not a great believer in corner deflectors, they just loose you volume, but they do strengthen the box and may provide places for grips and casters.
Regards,
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Tb46,
Thanks for the photo. This also gives some suggestions for foam damping material inside the horn that Jg was asking about.
Thanks for the photo. This also gives some suggestions for foam damping material inside the horn that Jg was asking about.
Xrk wow are you freaking kidding me, that is an 8FE200 doing full range on its own?
That is amazing! I'm sold!!
Now, another question: if that is a single driver and I still have one more available, is there any use for it injecting a little 100-150hz boost to increase max SPL? Kind of in the way you did with yours? Not really that big of a deal to me.. If I can drive that little 8FE200 with 150w contiuous that should afford me 100db to around 122db- correct? I'm not sure if that exceeds the 4.6mm xmax so please correct me if I'm wrong!
With my sub reaching 125dB at a minimum, this would seem to line up, I'm okay with LF being 3db higher than the rest.
Thanks for all of your hard work xrk, you really have gone above and beyond in my opinion to help me out. Somehow I missed your earlier calculations for the TH and just wanted to thank you. I tried a sim w/ 32" internal width and indeed it is much flatter response (I kind of said oh s*** at first thinking I made a mistake), but I don't plan on using any other kind of amplifier than the JL HD1200 anyway, so 1200w will be my max. The smaller width in that case reduces F3 a bit and decreases the peaks, but it doesn't increase the troughs at all and doesn't afford me any extra SPL that I can see. So, whew, onward. For a second I thought I might have no choice but to trim the pieces down to 32".
That is amazing! I'm sold!!
Now, another question: if that is a single driver and I still have one more available, is there any use for it injecting a little 100-150hz boost to increase max SPL? Kind of in the way you did with yours? Not really that big of a deal to me.. If I can drive that little 8FE200 with 150w contiuous that should afford me 100db to around 122db- correct? I'm not sure if that exceeds the 4.6mm xmax so please correct me if I'm wrong!
With my sub reaching 125dB at a minimum, this would seem to line up, I'm okay with LF being 3db higher than the rest.
Thanks for all of your hard work xrk, you really have gone above and beyond in my opinion to help me out. Somehow I missed your earlier calculations for the TH and just wanted to thank you. I tried a sim w/ 32" internal width and indeed it is much flatter response (I kind of said oh s*** at first thinking I made a mistake), but I don't plan on using any other kind of amplifier than the JL HD1200 anyway, so 1200w will be my max. The smaller width in that case reduces F3 a bit and decreases the peaks, but it doesn't increase the troughs at all and doesn't afford me any extra SPL that I can see. So, whew, onward. For a second I thought I might have no choice but to trim the pieces down to 32".
Thanks for these most useful suggestions and pic!
I think I'm still confused about how to do cleats though, do you have an example?
I don't think you'll notice the subs being only 3db "louder" than the tops. Many "pro" setups for live sound (dj stages etc) run the subs pretty hot. 10-15db or so.
That's what I thought, thanks. Yeah if these systems had a flatline response it seems that things would become earbleedingly loud in the highs.
Yeah I don't really prefer it. But I hear the subs run wayyy hot many places I go. People seem to like the "sick bass" lol
You are describing my friends to the tee 😀 hahahah
...and that is ultimately who I'm building this system for!
Sick bass, brah!
Luckily they are not "bro's", though 😉
...and that is ultimately who I'm building this system for!
Sick bass, brah!
Luckily they are not "bro's", though 😉
Hi Jennygirl,
Post #272: "...cleats...example?"
I'm just about sure you know what they are (cleats/glue strips) when you see them. Here are some examples. One way I have reinforced corners is taking cut-off corners from junk wood, and glue/staple those corner pieces into the enclosures inner corners. Seals and stiffens.
Regards,
Post #272: "...cleats...example?"
I'm just about sure you know what they are (cleats/glue strips) when you see them. Here are some examples. One way I have reinforced corners is taking cut-off corners from junk wood, and glue/staple those corner pieces into the enclosures inner corners. Seals and stiffens.
Regards,
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Okay that's exactly what I was thinking, but when I googled it there seemed to be a million different kinds of cleats! Thank you for the clarification 🙂