Can someone help me model a sub Please?

[Coheednme13]

Hey guys I've been absent from the forum for a while because I got the car audio bug bad, but I'm back because I have the DIY bug. My wife finally is letting me have a theater room. I need a sub. Money is really tight so I was curious if a car audio sub I have could work because it would help with cost tremendously. If not well I'll have to look for something else. The sub is a DLS audio is an OA12 it is designed to be an Infinite baffle sub.

If someone could help me figure if this sub is a good candidate for a ht sub I would appreciate it I have tried to use those programs but I just end up feeling stupid.


Here are the specs.
OA12
Size: 30 cm (12")
Impedance: 4ohm
Nom. power (RMS): 210 W (max 400)
Freq. range: 20 Hz-2 kHz
Sensitivity: 88.4 db
Voice coil diameter: 50 mm (2”)
Voice coil height: 34 mm (1.34”)
Re: 3.55 ohm
Voice coil inductance: 1.79 mH
BL product: 12.53
X-max: +-9 mm (0.35”)
Suspension compliance CMS: 167
SD- Effective piston area: 452.3 cm2
Resonant freq. (Fs): 37.8 Hz
Vas (liters): 48
Vas (ft3): 1.69
Qms: 3.47
Qes: 0.57
Qts: 0.49
Cone material: Coated non-compressed paper
Magnet weight: 80 oz (2,27 kg)
Magnet diameter: 5.71" (145 mm)
Installation depth: 6" (153 mm)
Mounting hole: 11.10" (282 mm)
Outer diameter: 12.28" (312 mm)
Weigth: 12.35 lb (5.6 kg)

 

[TLS Guy]

Hey guys I've been absent from the forum for a while because I got the car audio bug bad, but I'm back because I have the DIY bug. My wife finally is letting me have a theater room. I need a sub. Money is really tight so I was curious if a car audio sub I have could work because it would help with cost tremendously. If not well I'll have to look for something else. The sub is a DLS audio is an OA12 it is designed to be an Infinite baffle sub.

If someone could help me figure if this sub is a good candidate for a ht sub I would appreciate it I have tried to use those programs but I just end up feeling stupid.


Here are the specs.
OA12
Size: 30 cm (12")
Impedance: 4ohm
Nom. power (RMS): 210 W (max 400)
Freq. range: 20 Hz-2 kHz
Sensitivity: 88.4 db
Voice coil diameter: 50 mm (2”)
Voice coil height: 34 mm (1.34”)
Re: 3.55 ohm
Voice coil inductance: 1.79 mH
BL product: 12.53
X-max: +-9 mm (0.35”)
Suspension compliance CMS: 167
SD- Effective piston area: 452.3 cm2
Resonant freq. (Fs): 37.8 Hz
Vas (liters): 48
Vas (ft3): 1.69
Qms: 3.47
Qes: 0.57
Qts: 0.49
Cone material: Coated non-compressed paper
Magnet weight: 80 oz (2,27 kg)
Magnet diameter: 5.71" (145 mm)
Installation depth: 6" (153 mm)
Mounting hole: 11.10" (282 mm)
Outer diameter: 12.28" (312 mm)
Weigth: 12.35 lb (5.6 kg)

This is your alignment. If money is tight I think this is worth building. The F3 is high for a good sub driver, however it can be tuned for an F3 just below 30 Hz. This is not spectacular but adequate. I assume this is a budget driver as xmax and power are a little limited, but an spl of 109 db is achievable at F3.

Box volume is reasonable and since this is not a high power driver the box can be tuned with two 3" tube vents flared at on end 14" long.

As near as I can figure, the driver displaces 0.14 cu.ft, which will need to be added to Vb as well as the volume of bracing and the amp. Box Pro allows for the fill volume.

 

[Coheednme13]

I'm trying to save money which sucks, I have heard form many car audio gurus that this sub is a jekyl and hyde. On paper it seems like a conservative sq sub but when you actually put power to it that it can really go low with a lot of output. They say it is very overlooked for this reason and you can get them really cheaply. I bought mine for $60.

 

[Coheednme13]

Thanks so much TLS guy for doing that for me. Did you try to model the sub sealed? I know that is what is reccomended for the sub by DLS. It is made for infinite baffle, sealed, or sealed bandpass. I'm not trying to be a pain just curious because I don't know what I'm doing. So should I only give it 200 to 400 watts?

 

[TLS Guy]

Thanks so much TLS guy for doing that for me. Did you try to model the sub sealed? I know that is what is reccomended for the sub by DLS. It is made for infinite baffle, sealed, or sealed bandpass. I'm not trying to be a pain just curious because I don't know what I'm doing. So should I only give it 200 to 400 watts?

In a closed box it is a car thumper. F3 is high. You could give it probably twice the power in a sealed box as the cone movement is controlled by the air compression. At only 9 mm xmax there is not enough linear motion for Eq.

As has been stated before in these forums, a sealed box will have an F3 above the sub range, and therefore require Eq. This requires a very expensive driver, that can handle a lot of power, with a linear excursion of around 30 mm. That can't be done on the cheap.

So for what you paid you will have a fairly decent budget sub if build the ported design. The driver actually models best in a ported enclosure, but I suspect the manufacturer likes sealed as I'm sure you could destroy this driver easily with too much power in a ported box. I would not give it more than 250 watts, may be even a little less than that.

This is a sealed box with a Qtc if just below 0.7. If you enlarge the box the driver takes less power, and F3 extends barely at all and Qtc falls, so to you it would sound as if it has less bass. Here is the sealed alignment.

Name: OA 12
Type: Standard one-way driver
Company: DLS Audio
No. of Drivers = 1
Fs = 37.8 Hz
Qms = 3.47
Vas = 47.9 liters
Cms = 0.167 mm/N
Mms = 107.5 g
Rms = 7.36 kg/s
Xmax = 9 mm
Xmech = 13.5 mm
P-Dia = 240 mm
Sd = 452.3 sq.cm
P-Vd = 0.407 liters
Qes = 0.57
Re = 3.55 ohms
Le = 1.79 mH
Z = 4 ohms
BL = 12.53 Tm
Pe = 210 watts
Qts = 0.49
no = 0.438 %
1-W SPL = 88.56 dB
2.83-V SPL = 88.4 dB
-----------------------------------------
Box Properties
Name:
Type: Closed Box
Shape: Prism, square
Vb = 0.721 cu.ft
Qtc = 0.696
QL = 20
F3 = 65.54 Hz
Fill = heavy

So sealed it is of no use for home HT.

Since you are inexperienced, I'm not going to get into band pass subs. You have to have experience and expertize for those and know their limitations and problems.

I did a quick look with a second order band pass model. F3 is 37, the band width is 60 Hz, so usable frequency range is 37 to 100 Hz. The sub is 18db down at 20 Hz rather than 12 db for the Qb4 model. The only advantage is that you save a bit if volume which is useful in a car as total volume goes down to about 2 cu.ft. However band pass units give up power bandwidth, as only the port is radiating sound and distortion is high for bandpass boxes. Just about acceptable for second order, but not for third and fourth order band pass designs, although Dr Amar Bose does not care about the huge distortion inherent in these alignments. With this alignment driver is absolutely maxed out at a drive power of 200 watts, by xmax limit.

 

[lsiberian]

For 45 you can use this driver

http://www.diycable.com/main/product_info.php?cPath=24&products_id=674

You will probably want to get an eq at some point and you will need to build it sealed as large as you can manage.

Of course you are severely volume limited at 100db, but it extends 20 24 hz in a 5 ft sealed box.

 

[TLS Guy]

For 45 you can use this driver

http://www.diycable.com/main/product_info.php?cPath=24&products_id=674

You will probably want to get an eq at some point and you will need to build it sealed as large as you can manage.

Of course you are severely volume limited at 100db, but it extends 20 24 hz in a 5 ft sealed box.

That driver has a max power of only 300 watts and an xmax of 13mm. Sensitivity is below 81 db. So there is no room for Eq, and I would say building a 5 cu.ft. box for a driver with those specs would be a waste of effort and space.

The OP's driver is pretty sensitive, because Fs is fairly high. So his driver will produce the same spl as that driver would with 800 watts, and his driver only requiring 200 watts. In my view for $15 more the OP's driver is much more promising. I think if he builds the Qb4 box he will have a very decent sub for the money, not the lowest F3 perhaps, but in the useful range. The box is compact and he can use a couple of tube ports. So I think it would be a useful project for him given the budget constraints. After all options are slim to none for that money.

 

[Coheednme13]

I also have a JL Audio 10w3v3. I really want to get a tc2k but I can't find one for sale. I also thought about a tc1k any thoughts on other drivers would be appreciated.

 

[TLS Guy]

I also have a JL Audio 10w3v3. I really want to get a tc2k but I can't find one for sale. I also thought about a tc1k any thoughts on other drivers would be appreciated.

Why did you not say you had a decent driver?

Now you can build a sub.

Name: 10W3v3
Type: Standard one-way driver
Company: JL Audio Inc
No. of Drivers = 1
Fs = 32.97 Hz
Qms = 7.027
Vas = 32.17 liters
Cms = 0.19 mm/N
Mms = 122.4 g
Rms = 3.61 kg/s
Xmax = 14 mm
Xmech = 21 mm
P-Dia = 209.6 mm
Sd = 345 sq.cm
P-Vd = 0.483 liters
Qes = 0.533
Re = 1.7 ohms
Z = 2 ohms
BL = 8.995 Tm
Pe = 500 watts
Qts = 0.495
no = 0.209 %
1-W SPL = 85.37 dB
2.83-V SPL = 92.07 dB
-----------------------------------------
Box Properties
Name:
Type: Vented Box
Shape: Prism, square (optimum)
Vb = 2.485 cu.ft
Fb = 22.94 Hz
QL = 6.68
F3 = 22.65 Hz
Fill = minimal
No. of Vents = 1
Vent shape = rectangle
Vent ends = one flush
Hv = 2 in
Wv = 11 in
Lv = 43.68 in


You will need to build a slot vent, and have an amp that can drive a 2 ohm load. This sub has a beautiful response to just below 23 Hz. I don't have time to load the data now so you can see the really good graphs. If you have that driver, then for Heaven's sake use it!

 

[lsiberian]

I also have a JL Audio 10w3v3. I really want to get a tc2k but I can't find one for sale. I also thought about a tc1k any thoughts on other drivers would be appreciated.

That's an amazing sub. Use that instead.

 

[Coheednme13]

Well I thought that since it is a smaller driver that it would have less output.

I need to check the impedence of the sub. When I bought it I had an amp that would do 8 or 4 ohm loads at the same wattage so I can't remember what impedence it is.

I also have a JL 13TW5 flat sub with a 2.5" mounting depth I wonder what that would be like it has to be sealed it needs the pressure

 

[lsiberian]

Well I thought that since it is a smaller driver that it would have less output.

I need to check the impedence of the sub. When I bought it I had an amp that would do 8 or 4 ohm loads at the same wattage so I can't remember what impedence it is.

I also have a JL 13TW5 flat sub with a 2.5" mounting depth I wonder what that would be like it has to be sealed it needs the pressure

Why don't we just list all the drivers you have and quit playing this back and forth game.

 

[Coheednme13]

those 3 subs are the only subs I have

Well I'm wondering if I should just wait and build an uber sub instead of wasting money on wood for a sub I know that I'll want to replace soon got any suggestions I'm thinking that a tc2k is what I need

 

[Coheednme13]

is there any subs that will give me low extension with 100 to 110db 20hz response with a smaller footprint than the kappa sub

 

[lsiberian]

is there any subs that will give me low extension with 100 to 110db 20hz response with a smaller footprint than the kappa sub

There are subs capable of that. But chasing the extension is a mistake often made. I suggest you build the best sub possible. Most stuff is in the upper range anyway.

 

[Coheednme13]

Let me just say that I'm sorry for being a noob I hate to ask questions that bore or aggrevate people. I will be using Emotive ERM-1 monitors in a small room. I mean like bedroom small. Does it matter what sub that I build. I want the monitors to blend well with the sub. As most know the ERM-1's drop off dramatically below 80hz. I just don't want to go from a 5.25 midwoofer to a 15" low end monster and have nothing in the middle. Now based on this knowledge can anyone give some suggestions. Thanks to all for the advice really awesome.

 

[TLS Guy]

Well I thought that since it is a smaller driver that it would have less output.

I need to check the impedence of the sub. When I bought it I had an amp that would do 8 or 4 ohm loads at the same wattage so I can't remember what impedence it is.

I also have a JL 13TW5 flat sub with a 2.5" mounting depth I wonder what that would be like it has to be sealed it needs the pressure

You can't choose a sub driver by the square inch. That is not the way it works. Your 10" driver is far superior to your 12" in every way.

Both of your JL audio units are far superior to your 12", and both produce an spl of 114 db.

The sub driver I would use is the 10" JL 10 W3V3. That has the smallest cabinet, and an F3 close to 20 Hz. The 13 TW5 needs a larger enclosure and has 6db less output at 15 Hz. None of your drivers are suitable for HT sealed. They are maxed out as far as cone excursion and F3 is too high with no the only possibility for Eq being to greatly reduce the average level.

Here are you files.

JL 10 W 3V3 vented.

JL 10 W 3V3 sealed.

JL 13 TW5 vented.

JL 13 TW 5 sealed

Build the first one the 10 W3V3 vented, it will be ideal and more for what you want. You don't need to look for or spend money you don't have on any other drivers.

So now you can build with confidence.

Sorry I was slow getting this posted, but I had a little aggravation with my web site I had to fix. Hopefully you can download the files now.

 

[Guiria]

That JL Audio 10 would make a fine sub. I would not worry about looking to upgrade off the bat on something like a TC Sounds sub. Build the JL Audio and get your feet wet. After you've built the sub and enjoyed it for a while you'll be able to pick out the pros and cons of your DIY sub. The next go around you'll be able to make far more educated choices about what YOU want and what fits YOUR needs.

The fact that you can build your first sub with out having to buy a driver makes the JL a no brainer in my opinion.

Welcome to speaker DIY, it is the best.

 

[Coheednme13]

Is there some software that I can use to help me design the enclosure? Or if I paypaled someone some money could they help me come up with a design?

 

[Coheednme13]

TLS thanks so much for taking the time to model these for me you are truly a stand-up guy in my book especially taking time around the holidays. I do have a question though it appears from your graph that the 10w3 has a vent velocity of 20m/sec at F3 is that acceptable? Is there anything I can do to combat this?