Hi all, I'm new to this forum. I'm having a pioneer TS-W304R subwoofer. I want to make my first subwoofer enclosure by myself. This is for home theater application & the power of amplifier is 200W. I started with some software's like ajdesigner, WinISD, etc., Some of the required parameters are weird & I can't fill all the details because of inexperience. I'm using Lateral MOSFET SUB-AMP of Rod Elliott P101 design. I don't know how to select the beat frequency for home theater & required volume of the box etc., I can't find a perfect box for my subwoofer. Please anybody give me a good bandpass enclosure design for my subwoofer.
Where is this sub going to go? You do know you are posting in the HOME AUDIO section of the forum, right? We are going to assume you are putting this in a room in a home, not in your Subaru WRX.
No one can give you a "good bandpass enclosure design". You have to decide what you want from the total system (driver + enclosure) and balance that against the size and the complexity to build with any enclosure type you select. If you have only very basic tools to work with, then you need to take that into account and build a very basic box. Speaker building normally requires a fair amount of space which can be dedicated to the project as the enclosure is glued up. More clamps than you originally bought is a common thing with speaker enclosures. If you don't have a table saw and a large table for support on your saw, then you need to consider the smallest box size you can make work.
Next you have to decide how large the enclosure will be vs the bass extension you desire vs the enclosure type. Those three values are tied together and changing one will affect the other two.
Trying to reach 20-27Hz extension is a bit absurd in most systems since there are no instruments with that fundamental frequency. Additionally, the enclosure (room size) in which you place your enclosure will also determine the bass cut off frequency. In reality, where you place the box is almost as important as the enclosure type since placement and room reinforcement will affect low frequencies.
I would suggest you first consult Pioneer's manual for the driver. It provides several suggested enclosures and you can pick which is best for you and your building skills and tool assortment. A simple sealed enclosure is one of the best as a first build since the overall size of enclosure and its internal volume are not as critical with this design. On the other hand, vented enclosures tend to be more enclosure dependent (internal volume capacity) and the position and shape of the vent will affect bass response in any other type of enclosure.
You can make the driver see a larger or small enclosure, and thereby affect bass cut off and "Qts", simply by the amount of stuffing you use in a sealed box. The only real downside to a sealed enclosure, IMO, is you give up 3dB of electrical sensitivity. The driver you own is rated at 95db w/ 1 watt so you have a bit to play with and you'll still have high volume potential. A sealed enclosure rolls out its bass extension at half the rate of a vented system, it represents a second order filter. This means you have deeper usable bass further down into the frequency range with a sealed box.
Otherwise, try the Pioneer owner's manual. Or contact the retailer who sold you the driver. They should be willing to give assistance after the sale. If they aren't, return the driver for a refund and buy from a retailer who doesn't see the customer as just a number.
Or look through the web for others who have used the driver and can give details for the enclosure they built/used. But, if you are inexperienced in the calculations and you are inexperienced in building a solid and well braced enclosure, relying on someone else to provide the numbers isn't going to help you out. You can go buy a generic box and do just as well, if not better, in that case. Learn from this build and then make a slightly more complex system next time. Each build can be a bit more complicated as you learn how to build an enclosure which isn't just a copy of someone else's numbers.
Particulary if this is for your home - you do know you are posting in the HOME AUDIO section, right? - I'd say start with a sealed enclosure.