Using winisd for a plugin i found for d2 18 q 2010 it says i just barely bottom out at 700 watts but at 1000 i EASILY bottom out at 17 hz and anything lower then that bottoms hard, i plan to be pushing this near limit with cooling package so idk :/

I have to say those aero ports work very well. I have 3 4" for my q 18". I actualy temporarily used it for my ht with 2 4" aeros tuned to 24 hz. And the q does sound amazing in ht environments. Never got to put more than 250 watts on it though. Still more than enough for my living room

There is over 3 inches of mechanical excursion (xmech) on these subs, and winisd is a bit misleading, did you enter 28mm under xmax, or 56mm? It should be 56, as winisd is peak to peak, and the specs for the sub under the site are one way limits. I don't think you will be able to bottom them out whatsoever, I have never once been able to do that with mine, and I am running over twice what they are rated for! If I remember correctly, the Q18's are suspension limited as well, so the spiders will give out before the coil starts clanking.

Edited December 9, 201014 yr by The SSD Madman

There is over 3 inches of mechanical excursion (xmech) on these subs, and winisd is a bit misleading, did you enter 28mm under xmax, or 56mm? It should be 56, as winisd is peak to peak, and the specs for the sub under the site are one way limits. I don't think you will be able to bottom them out whatsoever, I have never once been able to do that with mine, and I am running over twice what they are rated for! If I remember correctly, the Q18's are suspension limited as well, so the spiders will give out before the coil starts clanking.

GREAT to hear i think i may have my final box... 28x30x26 around 10 ft3 after bracing. 3.5X42 slot port bringing the tune to 22.6 and final volume of 7.8 after displacement and port. now i am not sure what size cuts i have to make and am hoping my math is right lol.

Sure you don't want to tune a little lower e.g. 18hz.. Just my .02.

Overall it looks like your on your way.

Sure you don't want to tune a little lower e.g. 18hz.. Just my .02.

Overall it looks like your on your way.

Yeah i am going to be using it for music mostly so the extreme lows dont appeal to me too much. allthough the 15 it is replacing is tuned to 19 hz. i dont think i will miss anything though beuause this has so much more power i think it will still handle low notes better then what i have now.

Very nice!

just build it up in sketchup, and then you can measure your panels from there. Its a bit hard to get a hang of sketchup, but i have found the tutorials in the help center to be very useful. Always start with your bottom panel, then push/pull it to the thickness of your wood, and start drawing your edge panel dimensions onto it and use the CTRL modifier with push/pull+ to bring your walls and ports up from there. You will be designing boxes with ease in no time! It usually only takes me a few minutes to sketch it once I get the design finalized. Sometimes I will design them on the fly while I am drawing them up too.

i am having a hard time finding out what measurements i need to get the tune i want. i know i posted some before but i am confusing weather i need the volume of the box before the port or after entered into winisd.

just build it up in sketchup, and then you can measure your panels from there. Its a bit hard to get a hang of sketchup, but i have found the tutorials in the help center to be very useful. Always start with your bottom panel, then push/pull it to the thickness of your wood, and start drawing your edge panel dimensions onto it and use the CTRL modifier with push/pull+ to bring your walls and ports up from there. You will be designing boxes with ease in no time! It usually only takes me a few minutes to sketch it once I get the design finalized. Sometimes I will design them on the fly while I am drawing them up too.

I have a sketch of what i think is right, could i email the sketch to you to double check the numbers?

WinISD always assumes that the volume you enter is AFTER port and driver displacements, so make sure to factor this into your design measurements.

Sure- go ahead and email me the sketchup file, an I can take a look at it for you and double check the numbers.

I'm super excited, my SSD18's have been featured on Car Audio And Electronics home page, and also in the featured picture gallery! Check it out at CAE Featured Picture. I also got news today that a number of shops in the area will soon be contracting me to design and build "stock boxes," as I like to call them, since SubZero is going out of business (no surprise there, such garbage engineering, if you ask me!!!) and they will be looking for a new enclosure supplier.

WinISD always assumes that the volume you enter is AFTER port and driver displacements, so make sure to factor this into your design measurements.

Sure- go ahead and email me the sketchup file, an I can take a look at it for you and double check the numbers.

I'm super excited, my SSD18's have been featured on Car Audio And Electronics home page, and also in the featured picture gallery! Check it out at CAE Featured Picture. I also got news today that a number of shops in the area will soon be contracting me to design and build "stock boxes," as I like to call them, since SubZero is going out of business (no surprise there, such garbage engineering, if you ask me!!!) and they will be looking for a new enclosure supplier.

I'm at school on my phone so I can't send them now but I remember a few things about it. It's 10 ft cube after all displacements its either 14 or 16 all together. The port was a slot port about 95 inch surface area which should be plenty at 3.5 inch tall 47 inches long if I calculated it right around the corner. Tuning was about 20.5 hz. Double baffle. I'm almost positive all measurements and displacements are right, making sure by running them by you. I'll send it in like 4 hours when i get home. Thanks again.

That's awesome I've seen your videos and they move a lot of air it makes me excited to build my Q. Can't wait. That's awesome that they want you to design boxes!!

I found an AWESOME AMP to use instead of the Behringer. I geuss Mackie is doing bad with buisness and their Mackie M2000 which specs the same as the Behringer 2000 W at 4 ohms bridged is only $300 reconditioned http://www.pssl.com/Mackie-M2000-AMP-Power-Amplifier-400W--8-ohms also see it for 250 on ebay. a quick google search brings back places selling it for $750-$1100. if i were to grab this amp off this deal could i use it just like the Behringer or will i have any problems anyone knows of getting it connected??

It uses the same connections as the Behringer, and its build quality looks great. I have talked to a few people on AVS asking about these amps as well, so I'm trying to find out if it would be a good buy or not. It looks like a steal at that price, though.

It uses the same connections as the Behringer, and its build quality looks great. I have talked to a few people on AVS asking about these amps as well, so I'm trying to find out if it would be a good buy or not. It looks like a steal at that price, though.

Digging deep into the manual i found this

"The M-Series amplifier expects to see a nominal signal level anywhere between the –10dBV “semipro” and

+4 dBu “pro” standards, meaning almost any line-level

mixer or other device can be plugged into the amp’s

INPUTs. Use the Gain controls to adjust the gain of the

amplifier to match the signal level you’re using."

so i think that means i dont have to worry about my sub preout being too low and having to buy one of those boxes. reading reviews online people say you can push these HARD!!! people will run them for hours gurring gigs hitting the clip limit (which you cant hear because of some technology they have) so it looks like its built really solid.

Take a gander at this discussion on pro amps. there is a ton of good info there about them. I am looking over your design now, give me a few more minutes to check the math.

I Read the thread, interesting. i know about the pre out voltage. im hoping the mackie will accept my sub pre out. none of the other amps say semi pro and pro, they all either say pro line levels or just the voltage.

Edited December 11, 201014 yr by drewlrox

Take a gander at this discussion on pro amps. there is a ton of good info there about them. I am looking over your design now, give me a few more minutes to check the math.

its 1:30 by me and im tired so im going to bed, unless your still on and have the calculations done/close to done. if not ill just see them tommorow. thanks for all the help i really appreiceate it. your help has saved me tons of research.

It looks good to me, the overall volume came out to 9.674 after displacements, and the port tuning is 21.9 hertz. The group delay is rather high for what I like to run @47, but the specs are according to the latest at fi's site. The parameters I have on my computer must be older models, they are showing a completely different tune.

When you tune around 20Hz or lower and only play an octave or 2 above, group delay really isn't a very audible problem.

Also don't forget that Passive radiators don't offer an advantage in group delay over standard 4th order vented alignments above resonance.....

Whats the point of tuning the box for subsonics, just to use it at 40 or 60 hertz? I think it should sound its best, right around its tuning frequency, and introducing group delay doesn't help that. Maybe I'm just too dam picky!

Well, because you usually net a very flat, low-ripple response when tuned around 20Hz or lower. This is when the very large, low tuned enclosures are very popular for H/T.

Tuning higher than that will sacrifce that bottom octave, and that bottom octave is where DIY wins hands down over commercial offerings....

My current subwoofers use 18" XBL2 XXXs. They are tuned at 18Hz and are in large, low tuned enclosures. They are only used for a little under 2 octaves as true subwoofers. Group delay doesn't even really enter the realm of concern down this low. My mains take over around 50Hz...

Group delay becomes a major concern in full range enclosures and subwoofers that operate above the bottom 2 octaves of the overall spectrum.

I guess all I am saying is, when you are building a subwoofer that is large and low tuned as you guys are talking in this thread, I would be more concerned with proper alignment execution and enclosure construction than group delay. Additionally, for movies and the use of source material from the LFE or similar mix, you are talking a lot of low frequency energy that will leave little to the listener to discern bad group delay.

Music is another story, but again, if you are talking the bottom 2 octaves, it isn't a huge concern as there isn't a whole lot down there anyway...

I think it is great how you are helping people out on here with box designs, and I am not trying to discount that fact.

It looks good to me, the overall volume came out to 9.674 after displacements, and the port tuning is 21.9 hertz. The group delay is rather high for what I like to run @47, but the specs are according to the latest at fi's site. The parameters I have on my computer must be older models, they are showing a completely different tune.

Yeah there is a newer Q file to download because they changed to the btl style magnet its kind of hard to find though.

Is this going to give me any problems? more then half my use is going to be for music!!!

No, it will be fine, the group delay is just a bit higher than what I like to see in the builds I do... It is still probably lower than many similar commercial designs (what similar designs?) though, if that gives you any idea.

No, it will be fine, the group delay is just a bit higher than what I like to see in the builds I do... It is still probably lower than many similar commercial designs (what similar designs?) though, if that gives you any idea.

haha allright cool.