Looking to build a sub in the next few weeks

[BLindsay]

Pretty much im bored, i like to build things and im not happy with the output of my Klipsch sub12.

In my car i have an Alpine Type R 12" ported on 600wrms. While its not the best SQ sub (its decent) it hits pretty damn hard and low on the box/amp combo. I want that (or close) in my room (12x16x7).

Here are the 3 setups im currently considering.

Alpine type R 12" with a 500w plate amp from eD
2x Alpine type R 12" with a 1300w plate amp from eD
1x Alpine type X 12" with a 1300w plate amp from eD

As far as the box well currently im thinking sealed. Mostly because unless im mistaken it generally has better SQ and can hit lower frequencies? Yeah i give up some output, but if im correct those setups should be alot louder then my current setup.

Id consider a sub from eD but im quite familiar with the Type R and Type X so i know what to expect. Ive built boxes for each and alpine is good at posting specs. Two Type R's or the Single Type X are about the same price.

Im guessing though if i went with the 1300w amp and either the dual Type X or Single Type X it should be pretty nasty

Also i imagine the two Type R's will be louder? but the Type is a better sounding driver.

[Big Daddy]

Check the DIY Subwoofer Building thread. There are plenty of good links in post #2. If you are building a subwoofer for home theater use, it is better to stay away from car audio parts and focus on drivers, cabinets, and amplifiers for home use. Although ED has many good options, including DIY kits, don't hesistate to check other sites such as Parts Express.

[BLindsay]

Originally Posted by Big Daddy

Check the DIY Subwoofer Building thread. There are plenty of good links in post #2. If you are building a subwoofer for home theater use, it is better to stay away from car audio parts and focus on drivers, cabinets, and amplifiers for home use. Although ED has many good options, including DIY kits, don't hesistate to check other sites such as Parts Express.

Yeah i saw the thread, its part of the reason i want to do it

Why though should i avoid car audio subs?

My only hesitation from parts express is that i wouldnt know whats a good one to buy, because i want to make sure its better then my current setup

[Blu-Dog]

Originally Posted by BLindsay

Why though should i avoid car audio subs?

You don't need to avoid them, but you need to be careful which ones you get. Xmax isn't the only criteria - you also need efficiency, which is usually a combination of quality voice coils and spiders, linear efficiency (no sloppiness in travel), decent surround flexibility, stuff like that.

A good driver of any type should be rigid throughout the travel of the speaker - perfectly flat from each point of max extension, and not rippling like a flag in the breeze. Many car audio subs aren't like that, so you wind up with lots of travel, but fuzzy sound, as one point of the driver surface reaches Xmax while another part is still catching up.

It's the difference between hitting an enemy with a Spartan war shield, or smacking him with a pizza.

You'll be fine with the R12's, or with Infinity Kappa's (my low-end favorite), or with Polk's SR line, or for the truly discriminating, any of the W7's from JL Audio. They use those for the Fathom and Gotham lines of home subs, with minor tweaks for max extension.

Cheaper subs - the low end Pioneers (nice high end subs in their line, but the cheapies are horrible), MX, Roxford Fosgate (Punch is overrated), and others, just don't make the grade for home audio. Some that are more expensive, but so inefficient that you need the Hoover Dam to supply power, are the Kicker line.

Subs designed for home audio are generally shorter in Xmax, and of lighter weight, to be easier to push with smaller amps. They're also optimized for ported applications, for the same reason. Take a look at your Sub-12 driver for an example - I'm sure it pumps (mine does, I have two and gave one to my kid) but the port is big enough to fire cannonballs out of it.

The point is, the shorter the Xmax, the less power required to complete the AC cycle generating sound. It hits, quits, rides to the other side of the wave, much more quickly, with cleaner results. It moves less air, for less sound pressure, so designers try to get efficiency by using the back side of the driver for sound generation - and release that sound through the port.

I prefer sealed. I don't know for sure if the inverse square law applies here, but from my experience, it takes at least twice, if not four times, the power to push a sealed speaker to generate the same power. Increase the Xmax, and that power requirement increases exponentially.

For me, it's worth it. I don't like port tuning - I'm not good at it, and I don't like putting refrigerator sized boxes in living spaces - and power is easy to get. Sound is not generated in your media at any given port tuning frequency; let the driver deliver whatever it's fed, and you'll get better sound anyway.

As BD noted in several threads, he and I agree that external power to a passive sealed speaker is a very good option. I use QSC amps for this, though they do make noise (the fans on all musician's amps are bolted to the frame of the amp, which is the source of the noise - the fans themselves are very quiet) so that's a compromise you may need to make. If you do use an ED plate amp, or to save money, use one of the BASH plate amps available at Parts Express, get the beefiest one you can.

One final note: clipping. Music with sustained low tones suck the life right out of sealed subs using plate amps, especially feeding long Xmax drivers. Movies generally don't, but sometimes a long rumble will just poop out a plate amp. Remember, car audio freaks use capacitors for exactly this reason - the internal capacitors on most amps just can't hold that much juice.

Your Alpines are absolutely fine for home sub duties. Run them sealed, go overkill on the amp (whatever type) and set it for half-power output, knowing the reserve is there for sustained low passages. Don't go cheap on terminal cups, seal it tight, and absolutely adhere to the Thiele-Small parameters for size (Alpine provides that, and you've done all this before, sounds like).

Have fun!

[BLindsay]

wow! thanks for the reply.

So i guess the single type r and 500w amp is out so im left with


Dual Type R 12's and the 1300w amp
Single Type X 12 and the 1300w amp

and if money permits i would consider
Either a 12w7 or a 13w7 on the 1300w amp

edit: damn it, i forgot the w7's are a 3ohm load. Im guessing the eD plate amp wont like 3 ohms?

Im leaning towards sealed right now. Worst case i could always build another box if i had to.


estimated costs of each are looking like

2x Type R 12 ($250) and 1300w amp ($450) = $700
1x Type X 12 ($250) and 1300w amp ($450) = $700

12w7 ($450) and 1300w amp ($450) = $900
13w7 ($650) and 1300w amp ($450) = $1100

Box im gonna say around $100ish (maybe more because i want it to be finished nice, my car audio boxes just have the standard carpet thrown on them)

And i bet i could get 200-300 for my less then 1yr old sub12

out of those 4 what do you think is the best setup?

edit: oh and whats your thoughts on down firing vs front firing? JL has their home subs front firing so i was leaning towards that currently




Ive just had first hand experience with Alpine and JL subs which is why i tend to lean towards them. In my car at one point or another ive owned

12" Type R
12" Type X
10w7
12w7
2x 12w6v2
12w6
10w3



thanks again for the help thus far. Looking foward to this build

[BillCinLR]

Check here:

http://www.hometheatershack.com/forums/diy-subwoofers/

This is full of resouces and plenty of build ideas.


Good Luck,

Bill C

[BLindsay]

Thanks I'll check that out. eD said they don't suggest 3ohm on that amp so I'm not sure what to do. I can try to find and amp that does 3 ohm or I asked eD if they have a sub comparable to the 13w7 that will run on that amp. The other thing the eD guy said there might be some things I can do in my build to try to raise the sub closer to 4ohm such as box design possibly?

[Driver_King]

The closest thing to a 13w7 from eD would likely be the 13Av.2.

[BillCinLR]

The only thing that will raise the impedance is to wire two of them in series, giving an impedance of 6 ohms. I haven't heard of any physical box manipulations that can change the electrical impedance of the driver.

Maybe you need to look at other manufacturer's drivers (AE, Exodus, RE, Rythmik, CSS, as well as ED to name a few). Many home theater drivers are dual voice coils at either 2 or 8 ohms each that can be wired in series or parallel to attain the 4 ohm load required.

If you are dead set on JL, then consider building passive subwoofers and drive them with an external pro amp (Behringer) that will provide 2,000 watts at 2 ohms.

Good Luck,

Bill C

[Beerserker]

I second the notion of doing some research at HTShack and AVS forums. Both have extensive Subwoofer DIY forums. Post your build here too though.

You can change speaker impedance with an autoformer. I've never seen one actually used though. Certainly not for a sub build. That's just more for information then any suggestion of using one.

You need to download WINISD or Unibox to model your build. It will give you a rough idea of what to expect for FR, SPL, box size needs, port length etc, etc. and you can tinker with options until you get the result you like.

If space allows I suggest a larger sub choice -15 or 18. I also have an Infinity perfect Kappa 12" in a ported box and it will play loud as hell, but 12" subs just don't deliver in the teens and twenties.

I like the Behringer EP 2500 or 4000 for powering subs. Loads of power and quite inexpensive. Snobs will bash them but they are amazing for subwoofer duty; 2000W bridged 4ohms for $250.00 to $300.00

Afraid I can't agree that short xmax subs are best for HT. Long Xmax subs like the RE XXX are proving to be very good HT subs, though a bit spendy.

[Beerserker]

Originally Posted by BLindsay

The other thing the eD guy said there might be some things I can do in my build to try to raise the sub closer to 4ohm such as box design possibly?

That is a rather strange thing to say. I've never heard of box design changing impedance. Stuffing the box can raise impedance but nowhere near a full 1 ohm from what I have seen.

[BLindsay]

Originally Posted by Beerserker

I second the notion of doing some research at HTShack and AVS forums. Both have extensive Subwoofer DIY forums. Post your build here too though.

You can change speaker impedance with an autoformer. I've never seen one actually used though. Certainly not for a sub build. That's just more for information then any suggestion of using one.

You need to download WINISD or Unibox to model your build. It will give you a rough idea of what to expect for FR, SPL, box size needs, port length etc, etc. and you can tinker with options until you get the result you like.

If space allows I suggest a larger sub choice -15 or 18. I also have an Infinity perfect Kappa 12" in a ported box and it will play loud as hell, but 12" subs just don't deliver in the teens and twenties.

I like the Behringer EP 2500 or 4000 for powering subs. Loads of power and quite inexpensive. Snobs will bash them but they are amazing for subwoofer duty; 2000W bridged 4ohms for $250.00 to $300.00

Afraid I can't agree that short xmax subs are best for HT. Long Xmax subs like the RE XXX are proving to be very good HT subs, though a bit spendy.

Well the 13w7 is a 13.5" drive and has pretty damn close the surface area of most 15's because of the surround design. I just loved the way my W7 sounded when i had it. I have also heard very good things about the RE XXX but how is it in the SQ dept. Yeah i want my sub to be loud but SQ is more important to me. Ill take a look at those amps you mentioned. Oh and if i remember correctly dont the home theater JL subs, Fathom and Gotham get pretty nasty(good) reviews?

Originally Posted by Beerserker

That is a rather strange thing to say. I've never heard of box design changing impedance. Stuffing the box can raise impedance but nowhere near a full 1 ohm from what I have seen.

this is what they wrote me, maybe it makes more sense to you. "The only saving grace of that would be if the impedence of the driver in the enclosure worked out to present a more nominal load that is closer to 4 ohms"

Originally Posted by Driver_King

The closest thing to a 13w7 from eD would likely be the 13Av.2.

When you say closest is it in the same ballpark or is that just the best they offer?

[Beerserker]

Originally Posted by BLindsay

Well the 13w7 is a 13.5" drive and has pretty damn close the surface area of most 15's because of the surround design. I just loved the way my W7 sounded when i had it. I have also heard very good things about the RE XXX but how is it in the SQ dept. Yeah i want my sub to be loud but SQ is more important to me. Ill take a look at those amps you mentioned. Oh and if i remember correctly dont the home theater JL subs, Fathom and Gotham get pretty nasty(good) reviews?

JL Audio is good stuff It's expensive though. For the price of the w7 you could have a Exodus 21". For HT it will annihilate the JL. But it needs a big box and way overkill for music. (not saying it would be bad for music, just more than necessary) I don't have my laptop right now or I could model you the difference between the two.

What is your ratio of music to movies? I know you are leaning toward sealed, and that's cool, but if the primary use is for movies, ported will offer better low end performance. Unless you want to EQ that is...

this is what they wrote me, maybe it makes more sense to you. "The only saving grace of that would be if the impedence of the driver in the enclosure worked out to present a more nominal load that is closer to 4 ohms"

Well, they have built more subs than me, but it seems like a stretch to think that a 3 ohm driver will become a 4 ohm driver once it's in the box.

[BLindsay]

pretty balanced between music and movies, but i would say my music peformance is more dissapointing with my current sub. Really looking for that hard punch that you can feel.

And i was going for sealed cause i thought it was better SQ and i thought it went lower then a ported box??

[Beerserker]

Sealed subs are considered more musical because of the support of the air cushion in the box. This helps control the cone, and protects from bottoming out. They are more forgiving of driver and amp shortcomings in terms of playing cleanly, (they don't like weak amps though, just saying the pressure stops slop). Also, most music doesn't have a ton of relevant material below 40hz, and a sealed sub will get you there, but they begin to roll off (lose output) at higher frequencies than ported subs. To get the absolute best from them, they need a parametric EQ and lots of power to help overcome the air cushion.
Ported subs can get a bad rap because if done poorly they can sound sloppy, boomy, or have port noise. Done correctly they play lower and roll off much later then the sealed counterpart. Movies also have relevant info into the teens that a non EQed sealed sub will miss out on.

Sealed features: Easy to build, no highpass filter required. With EQ-ing they can play as low as ported subs in most cases, smaller box.

Ported features: Plays lower and louder with no EQ, with proper design they are just as musical, more complex to build correctly, should use a highpass filter, larger box.

Both types can have good impact if quality elements and amps are used. Most first builds are done sealed because they are harder to screw up.

You'll learn a lot if you learn to use WINISD and model a few subs. Here is a tutorial on it's use if you are interested. http://www.hometheatershack.com/foru...inisd-pro.html

For your roughly $1000 a Behringer ep 4000 and two sealed 15's would be a nice setup and easy to build. You might even have enough left over for a BFD (EQ). If your ambitious, have a little more time to do some research and have better building skill, I say go ported.

[BLindsay]

Originally Posted by Beerserker

Sealed subs are considered more musical because of the support of the air cushion in the box. This helps control the cone, and protects from bottoming out. They are more forgiving of driver and amp shortcomings in terms of playing cleanly, (they don't like weak amps though, just saying the pressure stops slop). Also, most music doesn't have a ton of relevant material below 40hz, and a sealed sub will get you there, but they begin to roll off (lose output) at higher frequencies than ported subs. To get the absolute best from them, they need a parametric EQ and lots of power to help overcome the air cushion.
Ported subs can get a bad rap because if done poorly they can sound sloppy, boomy, or have port noise. Done correctly they play lower and roll off much later then the sealed counterpart. Movies also have relevant info into the teens that a non EQed sealed sub will miss out on.

Sealed features: Easy to build, no highpass filter required. With EQ-ing they can play as low as ported subs in most cases, smaller box.

Ported features: Plays lower and louder with no EQ, with proper design they are just as musical, more complex to build correctly, should use a highpass filter, larger box.

Both types can have good impact if quality elements and amps are used. Most first builds are done sealed because they are harder to screw up.

You'll learn a lot if you learn to use WINISD and model a few subs. Here is a tutorial on it's use if you are interested. http://www.hometheatershack.com/foru...inisd-pro.html

For your roughly $1000 a Behringer ep 4000 and two sealed 15's would be a nice setup and easy to build. You might even have enough left over for a BFD (EQ). If your ambitious, have a little more time to do some research and have better building skill, I say go ported.

Ive built ported boxes before i just thought i remember reading that ported subs can bottom out if below a certain freq. My current Alpine Type R is in a ported box and sounds pretty good. My last W7 was in a sealed box

And i dont want to do anything huge like dual 15's lol. In fact the 13w7 (if not the 13w7 then i would get a 12") is the biggest i want to go with. This is for my bedroom afterall lol

maybe ill just build a ported and a sealed box and try them both lol.

Will i be that much worse off with a plate amp? such as the 1300w one from eD? It seems to be less wires and 1 less thing i have to find a spot for lol.

[Driver_King]

No, you wouldn't be worse off. In fact, you'd be better off since the LT/1300 has better SQ than the Behringer amps and are much simpler to integrate into your HT system. You could do dual 19Ov.2's like I did (I know, you have a bedroom setup...so do I). I have miles of headroom that I may never actually never completely touch, which is really a great feeling, especially considering I have a flat in room response down to 10hz, with usable output around the 8hz range. Movies are breathtaking and music is incredibly effortless and detailed. With the size of the DIY A7-900 and the additional 15hz tuning, it's like having a massive sealed enclosure with insane output capabilities. In reality, you would likely be looking more at something like a sealed 19Ov.2 or two (for smoother response) for more comparable sound quality of a single 13w7 subwoofer.

[BLindsay]

Originally Posted by Driver_King

No, you wouldn't be worse off. In fact, you'd be better off since the LT/1300 has better SQ than the Behringer amps and are much simpler to integrate into your HT system. You could do dual 19Ov.2's like I did (I know, you have a bedroom setup...so do I). I have miles of headroom that I may never actually never completely touch, which is really a great feeling, especially considering I have a flat in room response down to 10hz, with usable output around the 8hz range. Movies are breathtaking and music is incredibly effortless and detailed. With the size of the DIY A7-900 and the additional 15hz tuning, it's like having a massive sealed enclosure with insane output capabilities. In reality, you would likely be looking more at something like a sealed 19Ov.2 or two (for smoother response) for more comparable sound quality of a single 13w7 subwoofer.

damn you could house a small child in that enclosure if yours lol. I really dont have the room for a box that big lol. Unless stacked the drivers vertically instead of horizontally like yours. And 2 of those are cheaper then a single 13w7 lol. So thats what, an 18" driver? I was thinking more like 12-13.5" due to space. 2x 16Ov.2 might be doable though. Whats the difference with thier e5 series subs?


edit: damn i cant do 2 of the 16Ov.2 cause they only come in dual 2 ohm voice coils.

How would a single 13Av.2 on the 1300w in a sealed box do you think?

[Driver_King]

Originally Posted by BLindsay

damn you could house a small child in that enclosure if yours lol. I really dont have the room for a box that big lol. Unless stacked the drivers vertically instead of horizontally like yours. And 2 of those are cheaper then a single 13w7 lol. So thats what, an 18" driver? I was thinking more like 12-13.5" due to space. 2x 16Ov.2 might be doable though. Whats the difference with thier e5 series subs?


edit: damn i cant do 2 of the 16Ov.2 cause they only come in dual 2 ohm voice coils.

You could always contact eD to see if they could dig up a couple of D4's for you. And yes, you can absolutely house a small child in there. The 19Ov.2's are 18" drivers, yes. I would have a chat with Brett or Alex tomorrow to see what options you may have. Their e5 subs replace the 13Ov.2 and 11Ov.2 subwoofers, no other subwoofers to my knowledge however. An e5.15 would be an upgrade over the regular 16Ov.2, if one were to exist. eD does produce custom underhung drivers for a couple of their HT subwoofers. I don't believe they are for individual sale and they require larger enclosures. At the same time, eD can make just about anything custom. The DIY Dual 13Av.2 Sealed Kit is a kickass option as well. Animo made one a few months ago. He loves it. Believe it or not, the DIY 13Av.2 Kit costs more than what I paid total for my own DIY A7-900.

[BLindsay]

Originally Posted by Driver_King

You could always contact eD to see if they could dig up a couple of D4's for you. And yes, you can absolutely house a small child in there. The 19Ov.2's are 18" drivers, yes. I would have a chat with Brett or Alex tomorrow to see what options you may have. Their e5 subs replace the 13Ov.2 and 11Ov.2 subwoofers, no other subwoofers to my knowledge however. An e5.15 would be an upgrade over the regular 16Ov.2, if one were to exist. eD does produce custom underhung drivers for a couple of their HT subwoofers. I don't believe they are for individual sale and they require larger enclosures. At the same time, eD can make just about anything custom.

yeah ill probably just end up talking to them and get some complete package from them.

http://www.edesignaudio.com/product_...roducts_id=849

that looks nice

Is that kit pretty much the DIY version of the A7s - 650 ?