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I have a 13w7 already so this is the sub I am working with. It sounded great in my car in a ported box. I would like to use it now for my HT, but I know little about HT, box types, and home amps. I am still learning and searching the net for other 13w7 home installs at the same time.
The size of the box is not an issue I can make it as big as needed, I want it to get REALLY LOW to where it can shake everything :yay2: and will rarely if ever use it for music.
So far from what I've read I'm gearing towards either an LLT and sono tube. Can anybody give me some numbers on how to build the box (enclosure size, port size and length)? From what I read there is software, but I don't know squat about anything dealing with Qs and stuff. What I do know is I can make a very nice box and am great with woodworking if I knew exactly what specs to make the box at.
I would like it loud as can be and also understand that driver excursion can be a problem if tuning a box to be real low.
Also any ideas of what amp to get? I currently have a Harmon/Kardon AVR 645 as a reciever and will need an amp for the sub. I don't care if it's a plate amp or what not, just want one that is good, preferably 300-500, maybe more if the amp is really worth it for my sub. I would prefer it to be as powerful as possible, but within range to prevent driver excursion.
Finally will I need a crossover? eq? subsonic filter? If so can anybody recommend some?


I know I'm asking for a lot and might even get flamed for not know enough, but I am prepared. I want to be able to do it right the first time.
 

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I am interested in the responses because i also have a jl w3v3 12 driver that im currently using that seems to be ok not sure what the real differences are between ht and car audio drivers either
 

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Hey there. Welcome to the forum. The 13W7 is a beefy driver and should do good in a HT type setting. The only problem with it is getting enough vent area to keep the port from compressing the output at the tuning.

9cu ft net tuned to 15hz looks pretty good. You'd need about 50sq inches of vent area but that'll make the vent length around 60inches. You could also use 3, 4" ports at about 49" long each. It'll take about 1300w before reaching xmax in that enclosure with that tuning. A slot port would probably be best and you can fold it inside the enclosure.

I'll help out a bit more later, but I have to take care of some things right now.
 

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Looks like Ricci has you well covered. If you have any other questions let us know! Are you able to crossover at 60Hz rather than 80Hz? If so this will allow for a port of sufficient cross-sectional area such that port compression is a non-issue along side port resonance.
 

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Discussion Starter #5
Looks like Ricci has you well covered. If you have any other questions let us know! Are you able to crossover at 60Hz rather than 80Hz? If so this will allow for a port of sufficient cross-sectional area such that port compression is a non-issue along side port resonance.
I'm not sure with my current subs I just have it set to lfe.
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On your receiver there is likely a crossover option. Typically they default to 80Hz, but that doesn't mean you can't use 60Hz. What are your main speakers?
I will have to check I will get back on that tommorrow hopefully. I'm currently running all jbl venue series but will probably be updating in the near future. I have the center, the stadiums as the front and the balcony in the rear
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Did you want to do a sonotube build or a box type build? I'm just wondering because it will be difficult to fit the ports into a sonotube and a plate amp is also difficult to mount on a tube. I was thinking that you could use the ED LT1300 plate amp which is rated at 1300w at 4ohms. It costs $349. The 13w7 is actually a 3ohm driver, but I think the LT1300 should handle it fine even though it's only rated for 4ohms nominal. Here is the FR of the 9ft enclosure tuned to 15hz and the maximum spl with 1300w. Solid 114db output down to 14hz. The port airspeed shown is for a 40sq in slot vent.




13w7 2.JPG
13w7.JPG
13w7 3.JPG
 

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Discussion Starter #9
Did you want to do a sonotube build or a box type build? I'm just wondering because it will be difficult to fit the ports into a sonotube and a plate amp is also difficult to mount on a tube. I was thinking that you could use the ED LT1300 plate amp which is rated at 1300w at 4ohms. It costs $349. The 13w7 is actually a 3ohm driver, but I think the LT1300 should handle it fine even though it's only rated for 4ohms nominal. Here is the FR of the 9ft enclosure tuned to 15hz and the maximum spl with 1300w. Solid 114db output down to 14hz. The port airspeed shown is for a 40sq in slot vent.

View attachment 11929
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If I use a plate amp then def. a box build. And thank you guys very much for all the help you are providing, I was expecting to get flames for trying to use a car sub in HT!
 

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A good sub is a good sub. Doesn't matter what it was intended for, if it meets the right criteria for what you need the driver to do.:T. BTW yes you will need a HPF of some kind to protect the driver below tuning. Your reciever should have a crossover built in. EQ is always welcome for fine tuning the room response.

Mike,

What do you think about using the LT1300 for this? There was a guy at AVS who had trouble with his EP2500 bridged into a 13w7 and it was thought to be the impedence of the 13w7 dropping into the 3ohm range that was causing it. Do you know whether it has a HPF in it?
 

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If I use a plate amp then def. a box build. And thank you guys very much for all the help you are providing, I was expecting to get flames for trying to use a car sub in HT!
It's a great driver. A properly designed cabinet will yield incredible results. Remember, W7 drivers are used in the JL Fathom and Gotham series home subwoofers, and so far, these subwoofers are considered among the best retail subwoofers available by virtually every reviewer to try them so far. However, you should use a device like a DCX2496 by Behringer to shape the LF curve exactly as you prefer for optimum sound quality.

As for the Ep2500 amplifier, it should have no problem whatsoever driving the 13W7. 1st, I doubt the 13W7 is a true 3 ohm nominal driver; probably more like 3.5 or 3.6 Ohm nominal. 2nd, the Ep2500 can drive even 2 Ohms bridged according to the AVS forum tests. However, it does have reduced power available and will heat up more. 3.5 Ohms nominal should not be an issue.

Does anyone have an actual impedance measurement plot for the 13W7?

-Chris
 

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Discussion Starter #13
do any of these amps have a subsonic filter? My understanding is I will need one???
Also if I set my xorver in my reciever to 60Hz whont that mean I will be missing by bass at 60Hz on to where my midbass will be kicking in?
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do any of these amps have a subsonic filter? My understanding is I will need one???
Also if I set my xorver in my reciever to 60Hz whont that mean I will be missing by bass at 60Hz on to where my midbass will be kicking in?
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The Ep2500 has a filter I believe, but it is too high for HT use.

Really, I recommend a DCX2496. This will let you set a subsonic filter and set the crossover ideally, in addition to room corrections and response shaping to your preference(s). Also, you would eventually want to route your mains through the DCX also, to get the best possible SQ from the set up, if you plan to use it for critical music listening. However, if only for HT, I would not worry about routing the mains through the DCX.

-Chris
 

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Based on the 13W7 data in WinISD Pro, you can get a slot port with 54 square inches cross section, at 58 inches length, no problem, in a 10 cubic foot box. This moves your air port velocity down to much better levels to prevent compression at and around the tuning frequency. This also places port resonance high enough for you to cross safely at 80Hz, assuming you use a 4th order electrical crossover slope.

Note: I would recommend testing the actual T/S parameters for the woofer before building a cabinet. I have had 2 pairs of JL 8W7 drivers, from different production runs, and most of the parameters tested very close to factory, except VAS. VAS was almost 1/2 the factory spec on all of the units. This is a sensitive critical parameter to calculate cabinet parameters. A Dayton Woofer Tester 3 is $100 and even comes with the scale to measure your mass for compliance testing. Just a suggestion to ensure the most accurate cabinet design for your project.

-Chris
 

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Discussion Starter #17
Based on the 13W7 data in WinISD Pro, you can get a slot port with 54 square inches cross section, at 58 inches length, no problem, in a 10 cubic foot box. This moves your air port velocity down to much better levels to prevent compression at and around the tuning frequency. This also places port resonance high enough for you to cross safely at 80Hz, assuming you use a 4th order electrical crossover slope.

Note: I would recommend testing the actual T/S parameters for the woofer before building a cabinet. I have had 2 pairs of JL 8W7 drivers, from different production runs, and most of the parameters tested very close to factory, except VAS. VAS was almost 1/2 the factory spec on all of the units. This is a sensitive critical parameter to calculate cabinet parameters. A Dayton Woofer Tester 3 is $100 and even comes with the scale to measure your mass for compliance testing. Just a suggestion to ensure the most accurate cabinet design for your project.

-Chris
Chris you think you can send me some graphs for the specs you are talking about?Going by me using the ep2500 and the processor you mentioned.
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Chris you think you can send me some graphs for the specs you are talking about?Going by me using the ep2500 and the processor you mentioned.
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I don't usually take the time to take screens and post them from a modeling program, but I'll try to come back and do this for you within the next day. Is their any special thing or filter you want me to model?

-Chris
 

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Discussion Starter #19
dcx2496 and ep2500 is what I'm deciding to get as of now. I do t know much about anythng in audio other than," that sounds clean...", I guess model it to where I'm pushing the amp at max on the 13w7 and see where I need my subsonic setting at to prevent over excursion.
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dcx2496 and ep2500 is what I'm deciding to get as of now. I do t know much about anythng in audio other than," that sounds clean...", I guess model it to where I'm pushing the amp at max on the 13w7 and see where I need my subsonic setting at to prevent over excursion.
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Well, that's actually quite easy. The DCX does not have ability to set filters below 20Hz. While this may seem to high, it's not really. You can easily extend the actual filter by for example setting high pass filter to 20Hz, 2nd order, Butterworth. Now add a single parameteric band at 20Hz in the EQ section on the unit, set to Q of 1.5 and gain of +4 dB. This will counteract and extend the roll off, giving you an effective roll off on the 13w7 of -3dB around 17Hz and -6db around 14hz, with rapid roll off after this; exactly what you want with this 10 cubic foot cabinet tuned to about 16Hz to prevent excessive excursion under this tuning frequency.

I optimized the 10 cubic foot enclosure a little more and came up with a port of 60 square inch cross section. 12" wide x 5" high x 57" long as an example of an ideal slot port. Again, this is based on the 13W7 specs in WinISD. I always recommend breaking in and actually measuring the T/S parameters of the driver you use so that the model can be as close as possible.

-Chris
 
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