95Honda

It is still never. What happens is, they change something else that they didn't take into consideration, like airflow....

Any panel resonance ("flex") at all defeats SPL. You can never predict nor really control the phase differences between the panel and system. All flex is bad.

The 6" port will have a little more surface area than a pair of 4"s, so I would go with the 6" if you are going round....

Couldn't be more wrong.... They don't need a ton of power, in fact they "need" less power than just about any other driver out there. Buy what you can afford. As mentioned, used will get you more for the money....

No limit on box size? Maybe just 60+ Hz? This is the loudest single sub you could get.... My link 10ft3 box tuned at 50Hz would get you well into the high 140s with less than 1000 watts....

There is no such thing as underpowering, and it doesn't hurt anything. If you run one amp on each coil you do not have to worry about matching levels in the slightest. This is a big misconnception. Match them close only so one doesn't run out of gas before the other. The only thing that will damage a sub is too much power. Those amps will work fine.

Ahhh, it not complicated. Pick a driver(s) that fit the criteria and someone will help you with the design. Then build the box....

The biggest downfall I see is all the increased mms to keep the cone behaving properly, and thus dropping efficiency. Look at the mms of a Solo-X 18, it is almost comical... But if you have a place where a square will fit right and allow you more cone area than something round, I don't see a reason not to use the one.... I think the argument if one is better than the other because of cone area is stupid, though....

For bandpass, you really need a woofer that is more suited for a medium to larger box and a have a decently low Fs. Something with a usable Qts also, like .4ish range... The problem with a the woofers you have been looking at is they are designed to work well in smaller enlosures (look at thier Vas). And this becomes a problem when you are trying to build a bandpass due to so much vent area needed. Unlike a normal vented 4th order box, bandpasses have all the output coming through that port. This is also why I would only use a 6" I.D. pipes as a minimum with the designs I mentioned. Do you already have the drivers? If not, and you want to do a bandpass these would be my choices: My link Good balance price/perfromance... Use single, or a pair in about 4-5ft3 total.. A pair in a bandpass would be very loud. My link Again, good balance price/performance. Use a pair. My link Very high performance, great SQ and parameters would lend to a great, flat response bandpass. Only need one of these and still have the right box size. My link Either of the FI X drivers would be suitable, if you use the 10s, you would want to make it a pair.

Ok, here is the deal. Those drivers (SA10) aren't easy to model in a usable size box when you factor in a decent sized vent. So, I have 2 possible alignments. #1 Peaky, but efficient with a decent vent size. Good response from 30-60Hz. I would use this for Rap music/showing off. 2ft3 sealed, lightly stuffed with polyfill. 1.25ft3 Vented, 6" I.D. round vent 31" long (obviously not all in the box) and a 1" layer of fiberglass lining the interior walls. #2 Less Peaky, less efficient with a long-ass vent. Good response from 30-75Hz. I would use this for normal music. 1.4ft3 sealed, medium stuffing with polyfill. .75ft3 Vented, 6" I.D. 42" Long (your gonna have to figure this one out) and a 1" layer of fiberglass lining the interior. None of these calculations take into consider vent, driver or bracing displacement, you'll have to figure that out. I wouldn't use les than a 6" I.D. vent for a pair of those drivers with any amount of signifigant power. Rememebr, the vent doesn't have to be straight and be in the box, let you imagination go here. If these won't work, you may have to look at different drivers. -Mike

That's pretty much what I pictured. I didn't forget about your design, I will get to it. Nice thing is, a little of the vent can be out of the box, this will make it nice if the vent ends up being 2 feet long....

The few DHC2200s I used were solid...

Sorry I didn't get a chance to do it last night, I'll see if I can model tonight...

Don't buy KNU for gods sake....

I would try and choose a lower bottom end cutoff. Try this and look for a drop in efficiency, that box is super peaky. I have some good software, I'll see if I model you something good tonight...

If you could get a schematic, I could maybe figure out a bypass for you. Without one, if you had an O'scope and audio oscillator I could talk you through measuring and modifying it. Can you post a pic of the pot?

Just a point on the dampening- Poly fill is not going to do much with a vented box. The reason behind this that once you have properly designed the box (which you have) the only point of any dampening materials will be to dampening harmonics/mechanical noises. At the frequencies a subwoofer operates at, the material has little to no deampening effect. The ideal way to dampen a vented subwoofer box (if you use any at all) is to line all the walls with some type of material that will attenuate the harmonics and mechanical noises, and leave the majority of the enclosure open, especially the pathway leading to the vent. If you start adding a ton of polyfill, you won't really help dampen harmonics and noise as much as lined walls, what you will do is begin to alter the Q of the alignment and impede vent flow, which mor ethan likely will start throwing off your predicted response. Robert Bullock, a pretty good reference on this, talks in detail in "Bullock on boxes" about the point of NOT using any dampening materials in subwoofer alignemnts due to the unintended changes in response they cause vs any benefit. Full range boxes are complete different due to the fact that you must deal with all the mid/high frequency energy. In the 100 or so successful vented subwoofers I have built, lining all the walls with 2-3" of fiberglass has seemed to offer the best results. I have tried everything from Black hole to home made crap with fiberous cotton/sand/latex mixes....

If you buy anyhting other than welding cable, you are throwing away your money for an inferior product. As for RCAs, try and buy something of decent quality, if anything, it is because of the ruggedness you get... Stinger, Rockford and all the other main stream brands are super rip-offs, almost to the point of absurdity... Knu has some good deals, but, they cannot compete with the quality and durability of welding cable. To be honest, the best RCAs you can get for the money, hands down, are Dayton brand from Partsexpress. They are better than any of the car audio brands, at any price. No shit.

Exactly what I was going to ask. If you aren't running roughly 4+ amplifiers off the same set of pre-amp outputs, you probably don't need one at all... One most newer H/U, the voltage drive is high enough and the output impedance is low enough, to drive almost any plausible load....

The power you will need will be determained by your enclosure. It has absoluetly nothing to do with the RMS rating. Make sure you can build, or have someone design and build you an efficient box, this may make it a little bigger than you first think, but this is how you use your power wisely... As long as the Hifonics amp is working properly, it's performance will be as close to any other class D on the market.... I used to repair car audio amplifiers on the side to make money. I looked at the output of many amplifiers.... The class Ds are generally about the same.... And unless they are not working right, they are all similarly efficient... Go to Walmart, buy that huge-ass yellow SOB battery that is like $100. It will outperform any "car audio" battery under a few hundred bucks... And you can take it back as many times as you want if you kill it, or just want a fresh charge... Make sure you secure it so it doesn't go flying around and short out somewhere... Use good wire, upgrade the "big 3". Don't buy any of your power wire from a car audio shop, or anywhere else that says it is "car audio" power wire. Use welding cable. Don't terminate the wire shitty. Either borrow/buy a crimper, or have the welding shop terminate the wire for you. They normally have large crimpers that will do this, and if you buy the cable there, they'll probably do it for free.... Also, don't think you'll need "car audio" terminals, if the welding shops sell the big-mofo copper ring terminals that will fit you application. You'll just need to use something like NOALOX to coat them and the termination with due to them being bare copper. Paint them as a minimum after they are installed to places like the frame of the vehicle... This is how you do it right, on a budget...

Lol, I know about the shine part... I guess it shines when it is in thermal overload, compressed all to hell and nailing that awesome 10-20% distortion threshold....

You'll blow the sub. And it won't have anything to do clipping, gains, box, bass boost or anything else. It will only be because you will try and get a coil that is rated to dissipate the heat that 1000 watts generates to handle twice what it is designed for....... When people say on here they run subs at 2-3X RMS all the time, it is only because they really don't realize that the average power they are apllying is much less than they think..

I would try and at least use a 3" ID port for a pair of those 8s, as a minimum. A 4" ID port or larger would be best. It really depends on your power though, the area of the vent has nothing to do with the box size.... That is a stupid rule of thumb... I have installed tons of 8s. Hundreds really. With mosts drivers that have around an inch of throw, a 3" ID port for the pair is usually adaquate and is about as long as you can go unless your box is an extremely thin design.... For the Tangband (both neo and ceremic motors) and the RE and Parts Express Reference 8s, I almost always end up at .7-1ft3 per pair of 8s with a 3" ID PVC vent tuned at 30Hz... That always has seemed to work very well and not introduce a noticable amount of compression.... For all out efficiency at full stroke, I have used larger vents, like the ones in My Avatar, that is 3 x 4" ID Aeros for each set of (4) 8s.....

The only thing we'll ever agree on is shitty diapers, lol.....

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.