Automotive Sonosub

[frink]

Hi,
This is my first post here, so I hope I do it right.

I am just starting to build a LLT Sonosub for my home theater and thought it would be a good idea to build a Sonosub (non LLT) for my automobile.

Unfortunately I do not have the necessary skills with the design software, and I am hoping one of the Speaker Design God's ;x( ;x( ;x( would show me some mercy and "crunch the numbers" for me, please, please, please.

I would like to use 12" Sonotube (since I already have some)

Here is the info for the speakers I will be using:

PIONEER TS-W251F:
10", 4ohm,

T/S PARAMETERS:

Z=4
Fs=41
Pe=250
SPL=89.8
Re=2.6
Le=0
BL=11.32
Xmax= 6mm
Cms=0
Qms=6.57
Qes=0.34
Qts=0.33
Rms=0
Mms=0
Sd=0.031
Vas=31.5

Edited to add some xmax info.

[digital desire]

Just not going to get a lot of response with that xmax!

[frink]

OUCH!

LOL!!! like I said I am very new, that big fat 0 for xmax could be a problem. 8O

[frink]

Here are some more T/S numbers:
PIONEER TS-W251F
RE: 3
FS: 43.4
VAS: .04361
QES: .58
QMS: 8.36
SD: .0346
PE: 300
XMAX: .006
LE: .73
DIAM: 10
MMS: .05168
BL: 8.538
SENS: 89.88
QTS: .5424
ACCEL: 165.2

[J Walker]

Frink:

The best enclosure I could come up for these subs would be:

14" inside dia tube 22" long with 2(3" ports x 15.5" long)

this gives you a port tuning around 34hz. Max power of 175 watts before things go south in a big way!!!

Now..... I STRONGLY advise selling those subs! They really graph badly. I am sure you can find someone who really needs these subs!!

Hate to be the bearer (sp) of bad news. But 17 years of car audio, mainly enclosure design (not that it means much here) tells me you would be much better of with just about ANY other product.

[ThomasW]

It's a woofer not a subwoofer.

[frink]

J Walker,
Thanks for the info. I am not sure about the info I keep finding for these speakers since all the info I find lists them as paper cones when these are polypropelene.

I just had them laying around from an old car. I had them installed in 1990.

I guess I will look for something else. I still like the idea of a Bazooka style sono for the car.

Since I am starting fresh, any ideas? I do like 15" 's :-)

[frink]

Hi ThomasW,
Thanks for the reply. I was just trying to use something I had laying around, a small project while waiting for the TC2000 15" SVC for my home theater.

I would still like to build a new sub/woofer for my car, I just want to keep the cost low. :T

[frink]

Well duh! Maybe I should not be posting my car speaker questions in the HTGuide!
Sorry if I stepped on any toes.

[engr_dave]

Frink,
I think you came to the right place if you are seeking info on subwoofers. The administrators and members here have a wealth of experience and knowledge on the subject. The same laws of physics and acoustics apply to home theaters, listening rooms, and cars.

If you are looking for a enclosure for your woofer and are satisfied with moderate extension and output capability, then J. Walker provided a solution. You might be happy with this - it certainly will provide better bass than virtually any factory car system.

35 Hz is pretty deep for a car. The lowest note on a bass guitar is 42 Hz. If you want a true SUBwoofer for deep synth notes, pipe organs, or movie low-frequency effects, then you will need to select a different driver.

In any event, stay tuned to this DIY forum. I've found that the more I learn from these experts, the more fun I'm having... :T

[J Walker]

engr_dave:

I concur "completely" with your statement. " I've found that the more I learn from these experts, the more fun I'm having... "


frink:

What kind of vehicle are we installing this into? If it is a car with a moderate trunk I would recomend a

http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=295-455

in an IB setup this would hammer in a car. I will be glad to help with anything i can.

Just let me know.
J_Walker.

[frink]

Hi engr dave,
Thanks for responding.

I was never very impressed with the speakers when I had 2 of them in my Nissan coupe so I guess they wont do much better in a van.

I do want to build something that will sound very good. I do not have a theater in the van, I just listen to music.

I would love to be able to use the remaining 24" sonotube I have for this project. I would like to try a 15" driver in the 24" sonotube but not have it take up all the space in my van like an LLT sono would.

Is there a 15" woofer/subwoofer that could work in 24" Dia x 19" Long sonotube?
I figure i could offset the driver toward the edge and mount the sonotube on its side (like a kick drum) offsetting the driver would allow for multiple ports (if necessary) and with the driver at the bottom, gravity will help stabilize the speaker while driving (yeah right). 8O

[engr_dave]

Five cubic feet is a fairly large for a car enclosure. There ought to be at least a few woofers than would work well in that size vented box. I don't have access to woofer data or modeling software at the moment. What is your budget? How much power do you have? What is your crossover frequency?

Let me strongly urge you to bolt this thing down in the back of your van, whatever you do. A fifty-pound subwoofer flying at you at 60mph when you slam the brakes to avoid hitting the five-year-old who jumped into the street could ruin your whole day. :??

[frink]

Hi Dave,
I will definitely bolt this sucker in place. I don't need any more bumps on my head .
Budget: $200-250 for amp and speaker. Finishing under budget would be better.
My receiver has a built in low pass filter. settings are
off - 80hz or 120hz.

Can you mount the driver and vents on the same end of the sonotube?

[engr_dave]

Yes you can put the driver and port(s) on the same end.

I haven't done car audio in a while, but here's what looks like a decent deal on an amplifier.


$99. buyout at PartsExpress.

As far as drivers, I would need to start surfing the catalogs and doing some sims - hopefully some of the gurus who do this more frequently than I can chime in. My experience from HT/Music subs says that 140L (5 cuft) is on the large side for a sealed 15" but on the small side for a vented 15"... but I'm sure that there are drivers out there that meet your requirements. The Dayton RSS390HO might be a good choice. I have a bunch of sims on that one at home - I'll take a look.

[frink]

Hi Dave,
Thank you very much, and thanks to everyone who has helped or will be helping me, you folks are the best.

[engr_dave]

Definitely not the RSS390HO - I don't know what I was thinking. The HF is closer, but 5.0 cubic feet is a little large for this. The Dayton Titanic MKIII looks good in this size vented box, but it's $200. The Dayton QT-385-4 Quattro models pretty well, see graph below. Xmax is not huge, but the large cone area will still give you decent displacement... and it's only $86.

Anyway, there are some ideas to get started...

[frink]

Hi Dave,
Thanks again for all your help.

I am not dead set on the height of the tube. 24" Dia x 19" Tall is the size of a leftover piece of sonotube I will be using, so 24 x 19 is max size of tube (not accounting for the endcaps) so internal volume will be reduced by endcaps.

If I follow the Sonosub guidelines and use 1.5" endcaps, the effective internal tube length will be will be reduced by 3".

I would be more than happy to shorten the tube to match a driver and save some floor space, but I dont know how short I could go and not interfere with speaker height or port tube length.

[frink]

JWalker.
Thanks for your help. I obviously missed the end of your last post ops:

The Dayton QT-385-4 Quattro looks good to me.
15" Quattro

I was looking at the info for the "Quattro" and for automobile use it recommends for a vented box-
3.0 cu. ft.
4" x 17" Port
Lined Walls
F3 = 30Hz

24" x 12" (internal) Sonotube = 3.141 cu. ft.
But it is not long enough for the port.

Is there a port configuration that will work in this space?

[J Walker]

Frink:

Try this. 3.5ft3 total enclosure.(24" Sonotube x 13.25 long) with 2(3" ports x 9" long) 32hz tuning, with an f3 of 29hz. Should be low and loud with 300 - 400 watts.

Aim it into a rear corner. You may have to play with the "Face (of enclosure) to Wall distance" to achive the exact balance of loudness versis tight bass but this design will rumble nicely!

Note: Enlcosure face closer to the vehicle wall = louder BUT muddier(sp) bass.

Hope this helps.

J-Walker.

[frink]

Hi J Walker,
Thanks again for all your help.

The design looks good to me. It should look like a a big smiley face with a 15" "screaming" mouth. h:

I have one question, when you say 24" x 13.25" do you mean inside measurement not including where the end caps will be inserted (internal volume)? I assume you do but just want to make sure.

Considering that now I am listening to a 100 watt, 8" bazooka tube,
this thing should meet my requirements and then some. :T

I am not looking to win any volume/ SPL contests, I just want clean, effortless, bass. This is going in a mini-van that we spend a LOT of time in since everything is so far away up here.

[J Walker]

Frink:

You are correct. Sorry I did not make that clear. I always figure in all displacements when I quote airspace. So If you give the above enclosure 3.5ft3 internal volume, you just stuff in ports and a driver and you are golden..

I have found that you may need to play (reverse) the phase of the sub to make it "Blend" better with your existing mid/tweet system. Play with it and let us know.

Hope this helps.

[frink]

Hi J Walker,
Sweeeet :T !

Thanks again for all your help.
I will order the speaker and small parts and build this thing over the next couple weeks, actually the TC2000 for my LLT Sonosub should be here today, so I will cut all end caps and build both subs at the same time.

Wish me luck.
May the gods of thunder smile on me .

[DougyD19]

I've got an 8 inch Tangband sub in my car...that thing pounds like crazy for just being and 8 inch speaker -- but I guess the xmax of 12 mm is really helping lol. They are on sale too for $40.

http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=264-854