Yes, this is the latest and greatest, and last version of this sub I am going to work on. I'm happy with it. Actually, I'm very happy with it. It's the best sub I've designed to date.
In terms of the time required to put things into hornresp... it's the great equalizer. It at least gives you an apples to apples comparison, it's worth your time. What it doesn't show you is how port compression, etc... happen. Scott made an interesting comment... TH's 'bloom' where bass reflex 'wilt' at war volume.... and hornresp won't show you that.
As far as this particular cabinet in the above link? Hornresp says you'll get upper 120's per cabinet 40hz on up at 63v. A 40hz 48db/oct high pass makes this design PE limited, not xmax limited from 40hz on up.
I've personally run it up to about 125db with sine waves, so what I built vs. hornresp is on the money. The big difference between testing and hornresp specs are that I get a little more 40hz, and the notch at 170hz is a very narrow 2hz, 6db notch.
I cant wait to build it! Just to be clear >125db up in 2pi is what the sim says and your staying within x-max. Because there it is more efficent theory says the Power handling should go up.. be nice to put 900w in reliably.
TY for your quick response.. and of course your design.
Hi, I made Jbell's 8x4 sheet a little bigger, it does a little lower but isn't quite so efficient, it's around 400litres which is approx 1.5 times the volume but I have no idea how much could it would take to build, but I'm guessing around one and a half sheets. They light grey line is the single sheet box so you can see the difference.
Attachments
why is 900W chosen to be "nice"?
I could just as easily suggest that "nice" equates to 900mW or 9W or some other number plucked out of the air.
I think what we are gonna need here is an active DIY low cut filter. 24-48 db perhaps with the option of adding a switchable network to change the frequencies so you have a couple of choices. Perhaps 40hz and 35hz. Or a table with possible rc network vs freq so one could pick which cutoff they need. A variable pot like a crossover is nice but I strongly advise against it for reliability and unintended changing by small curious fingers.
On second thought a 12/24db 16khz low pass might be good to tack on as well
for the piezo crowd.
On second thought a 12/24db 16khz low pass might be good to tack on as well
for the piezo crowd.
ScreamerUSA's DIY low cut filter idea
I love the idea. Pop it into the amp rack. Load and lock... Very useful. I'd want it as discrete as possible, to prevent DJs etc seeing it and bypassing it to make things louder
I know we can have rules and contracts, but idiot-proofing is the way to go in my case.
Google found this for me: http://focus.ti.com/docs/toolsw/folders/print/filterpro.html
Good stuff!
Regards, Ben
I love the idea. Pop it into the amp rack. Load and lock... Very useful. I'd want it as discrete as possible, to prevent DJs etc seeing it and bypassing it to make things louder
I know we can have rules and contracts, but idiot-proofing is the way to go in my case.
Google found this for me: http://focus.ti.com/docs/toolsw/folders/print/filterpro.html
Good stuff!
Regards, Ben
DIY highpass for making things idiot proof? That's what xti amps are for....
Crown XTi-1000 Stereo Power Amp
Ben/Scott, I appreciate the thought, and I've even considered a 500uf passive or other type of active protection for my subs... but I just can't beat the simple setup of the xti.
$329 for full '3yr no fault' warranty b-stock... delay, dsp, eq, highpass, limiter, amp... all in a password protected, front panel lock out, 17lb all digital chassis.... Runs a pair of tops and a pair of subs beautifully. And limits out WAY before 900 watts per driver is possible. Using the internal 'Y' so that there is only a single audio input, and a single volume control even keeps peoples hands off of the sub/top volume ratio, so things always sound the way you want them to sound. To top it off -- 2 channel speakon cables even prevent mis-wiring on setup.... just chain all the speakers together.. Start on the side/top, go to the 2 center clustered subs, and then on over to the other side top.... beautiful.
I've been using nothing else for my school installs.... which have to be idiot proof....
Crown XTi-1000 Stereo Power Amp
Ben/Scott, I appreciate the thought, and I've even considered a 500uf passive or other type of active protection for my subs... but I just can't beat the simple setup of the xti.
$329 for full '3yr no fault' warranty b-stock... delay, dsp, eq, highpass, limiter, amp... all in a password protected, front panel lock out, 17lb all digital chassis.... Runs a pair of tops and a pair of subs beautifully. And limits out WAY before 900 watts per driver is possible. Using the internal 'Y' so that there is only a single audio input, and a single volume control even keeps peoples hands off of the sub/top volume ratio, so things always sound the way you want them to sound. To top it off -- 2 channel speakon cables even prevent mis-wiring on setup.... just chain all the speakers together.. Start on the side/top, go to the 2 center clustered subs, and then on over to the other side top.... beautiful.
I've been using nothing else for my school installs.... which have to be idiot proof....
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Jbell
I completely agree. Next time I have a wad of cash and can start from scratch I will do so with Crown XLI or XLS! (or maybe Peavey IPR 1600 dsp?)
However, currently I am sitting on a bunch of heavy old iron. I have a variety of soldering irons and tools and I like ScreamerUSA's idea.
But maybe I ought to grow up and sell the old iron...
Regards, Ben
P.S. over here it's €525 - so approx a very evil 666 US Dollars http://www.thomann.de/de/crown_xti_1000.htm
I completely agree. Next time I have a wad of cash and can start from scratch I will do so with Crown XLI or XLS! (or maybe Peavey IPR 1600 dsp?)
However, currently I am sitting on a bunch of heavy old iron. I have a variety of soldering irons and tools and I like ScreamerUSA's idea.
But maybe I ought to grow up and sell the old iron...
Regards, Ben
P.S. over here it's €525 - so approx a very evil 666 US Dollars http://www.thomann.de/de/crown_xti_1000.htm
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P7000S, P5000S, P3500S, P2500S | Power Amplifiers | Products | Yamaha Pro Audio
12db/oct... I wouldn't... nope, no way. 24db/oct minimum if you are going to set it at 40hz on this sub. And the yammy filter can be EITHER low cut or low pass... the xti allows you to HP butterworth 40hz@48db/oct, LP 95hz@24db/oct linkwitz riley, and then also use 24db/oct HP for your tops if you choose to run tops on channel 1, and subs on channel 2.
For a loud cheap DJ proof setup that fits in a corolla... I haven't found a setup that beats a pair of the half sheet beta12a tops, a pair of the single sheet subs and an xti.
An externally hosted image should be here but it was not working when we last tested it.
I installed a P7000S fed by a DCX2496 for the subs I built. Worked nicely. Sweet amp for sure. Built in filters are good as a fail safe but not steep enough for actual use.
Have to agree that the xti are practical, wish there was a PA plate amp that did the same without being too expensive. Active subs ftw.
jbell do you have any details in those tops?
Have to agree that the xti are practical, wish there was a PA plate amp that did the same without being too expensive. Active subs ftw.
jbell do you have any details in those tops?
Jim do you have to hold your tops back(pair of beta 12 half sheet) for the subs(pair of single sheet subs) to keep up?
Any pics to share with us of the finished tops and subs?
I just cut my cube up and will use it for braces on the new design. Didn't really have that much waste. May even get a few build pieces out of the scrap.
Thanks Mike
Well since I would like more sound instead of less I would like it to handle more power to get more sound. Nothing complex.
Since less power is wasted as heat, and the drivers rear is not enclosed there is the possibility that it can handle more power.
When I input the hornresp parameters I'm not seeing that eff@ 40 Hz... I get 92@40. Is there a revision I'm missing?
as I said... I get more 40hz than hornresp predicts,and the midbass notch predicted, is greatly reduced to only a 2hz wide notch. Other than that, what I built and the hornresp sim line up nicely.
You still want to run 2 cabinets or more to get good 40hz response.
wow... I've always been willing to help.
No pics at the moment, last set built are installed. I've got another hs gym to do in the next week or two, will snap a couple pics then. I'm experimenting with the 12" dayton conical waveguides on this set to see what there is to see, because it's just a pair of tops / pair subs installed up high on one end of a gym.
Your music vs mine will be different, your locations vs mine will be different -- so holding back tops or not will obviously be different. I can't say for sure what you'll expect. If I thought I could have given you a reasonable answer, I would have.
