Subwoofer Enclosure Help!! (2) SA-8's

[imhungnurnot 9]

Hey guys,

I'm pretty experienced with car audio so I decided I'd give home audio a try. I am VERY disappointed with the output of the subwoofer/enclosure. I think its due to poor driver selection and poor box design. However, I would like to salvage my build. I just want to know if I am wasting my time or if I should start allover again. I would really like to modify my current box if possible.

Goals:

The main use is for music, possibly some video gaming, and possibly some movies.

Background:

To begin, I had a pair of SA-8's in my car then when the v2's came out I decided that I would get a pair of v2's for my car and put the old pair in my house. This was mainly an excuse to cough up the money for the new v2's lol. So I bought a BASH 500W plate amplifier to power the pair. I then designed a box that I thought was a good design. I started off with the box design from my car. 1.3cuft with one 4" aero port tuned to 35Hz. I decided that I would need to increase the box volume since I would have less power to drive the woofers. I decided to go with 1.8cuft. I also dropped the tuning frequency to 26Hz.

Pictures:

Here is a picture of the setup in my car, and below is a couple of pictures of the enclosure I built for my house.

Problems:

First off, I noticed the speakers moving a lot and hardly any air moving the the port. Things shake in the house but the audible output is very poor. I used a 4'' aero port down-fired and I left about 3.5 inches between the exit of the port and the floor so that I would be able to breathe freely.

Initial thought was that the box was too large so I stuffed it with 7-8 pairs of jeans (tightly packed in). There was a a slight increase of audible output but nothing significant.

Solutions:

Next step is to take my box out of my car and see how it performs in the house since thats easy to check.

Do you guys have any suggestions? Is my design horrible? Is this not even worth trying to fix? Let me know what you think.

Thanks,

-Kelly

[Kanaworm$ 292]

Basically your using a limited throw driver that is not going to have a lot of output in lower frequencies in a home audio style setup. May want to try putting the enclosure in a corner and let the speaker load off the wall.

[imhungnurnot 9]

Basically your using a limited throw driver that is not going to have a lot of output in lower frequencies in a home audio style setup. May want to try putting the enclosure in a corner and let the speaker load off the wall.

Could you elaborate? The subs are moving at least 1.75'' full throw.. I've heard a single bose 5'' sub for a computer sound system get louder than what I have.. the 5" sub may have been moving 0.5'' full throw... lol

[Kanaworm$ 292]

Take your enclosure and set it at a 45 degree angle in the corner of your room and basically listen and then move the enclosure around until you find the sweet spot.

[imhungnurnot 9]

Take your enclosure and set it at a 45 degree angle in the corner of your room and basically listen and then move the enclosure around until you find the sweet spot.

I'll give that a try..

[Kanaworm$ 292]

Backtracking here, the SA-8 is not a limited throw woofer. But in the vehichle enviroment the cabin gain increases due to smaller area and more things for the woofer to load off.

Home audio means larger area with limited items for the woofer to load off of. Corner loading has worked for me in the past. But I am far from and expert.

[ricksi30 923]

I agree that it could be the placement in the room. I have a single sony 8 and when it is placed properly it sounds excellent. If it is placed in an open area I lose 75% of the output but it still rattles the windows. What is the size of the room?

[imhungnurnot 9]

I agree that it could be the placement in the room. I have a single sony 8 and when it is placed properly it sounds excellent. If it is placed in an open area I lose 75% of the output but it still rattles the windows. What is the size of the room?

Actually, I was testing the woofer in the living room (which is connected to the kitchen, and dining area). So I was testing in a very large space. I am planning to use it in a much smaller room. I will try it out in a smaller room and let you guys know how it turns out.

[///M5 2,833]

Sure they are wired in phase?

[imhungnurnot 9]

Sure they are wired in phase?

That would be a easy/simple solution. However, I actually double checked the wiring, but I can check again.

[duanebrow 6]

I had a 8" sub in my house that did very well in a 19*30 room. I would check do the battery check to make sure they are in phase. Move the sub around to check for the best placement. Both of these have been suggested already, so this is move of a +1. Also, did you model your design? Or just guess?

[imhungnurnot 9]

I had a 8" sub in my house that did very well in a 19*30 room. I would check do the battery check to make sure they are in phase. Move the sub around to check for the best placement. Both of these have been suggested already, so this is move of a +1. Also, did you model your design? Or just guess?

I checked with a battery and the subs are in phase.

I did not model the design since everytime I have done so WinISD tells me that I need get a bigger room... lol I'll tell me I need a 27 cuft box for a single 12...... I understand it is optimizing for a flat response, but thats just ridiculous. However, I am using a computer, and we all know "GARBAGE IN, GARBAGE OUT." There is a chance that I am doing something totally wrong. Have you ever experienced this problem when modeling enclosures?

Also, I did drive these subs with about 1500 watts for a while. Maybe they're cooked... I noticed that the pair measures 5.5Ohm when I wired it to be 4Ohm. So I feel that I may have done some damage to the coils. However, I did not notice a problem with this when running them in my car. Maybe I'm only noticing this now with the reduced power available? I would like to drop my v2s in the box to see, but I would need to cut the mounting holes larger...

[duanebrow 6]

I'm on my phone, so I might miss a few things. As far as the ohms being 5.5 - I would think that is fine. If you did damage to the drivers they will make noise when you use them. Like the vc rubbing. I have seen very high power change the T/S specs before though. But that is a whole different subject.

With WinISD, yes it will give you some crazy numbers. It is just giving you a starting point based off of the drivers specs. You need to play with the box size and tuning to get a design that works for you. Fwiw - many car audio subs have a qts of about .5 this makes the "ideal" size box very big. But if you use a smaller box it will give a boost to the low end and roll off slower below tuning.

Get the latest version of WinISD from their Facebook page. Try modeling your sa-8s in WinISD, put in your box design and see what you get.

[imhungnurnot 9]

I'm on my phone, so I might miss a few things. As far as the ohms being 5.5 - I would think that is fine. If you did damage to the drivers they will make noise when you use them. Like the vc rubbing. I have seen very high power change the T/S specs before though. But that is a whole different subject.

With WinISD, yes it will give you some crazy numbers. It is just giving you a starting point based off of the drivers specs. You need to play with the box size and tuning to get a design that works for you. Fwiw - many car audio subs have a qts of about .5 this makes the "ideal" size box very big. But if you use a smaller box it will give a boost to the low end and roll off slower below tuning.

Get the latest version of WinISD from their Facebook page. Try modeling your sa-8s in WinISD, put in your box design and see what you get.

Alright, thats what I did previously. But I felt like I didn't know enough about the output plots to really know what was going on. I also figured that the models would be very far off from the actual response, but I suppose using such a program gives a good guess...

[imhungnurnot 9]

Just did a little testing in a smaller room. WOW so much louder! I will do more testing when everyone is awake tomorrow. lol

[duanebrow 6]

I'm on my phone, so I might miss a few things. As far as the ohms being 5.5 - I would think that is fine. If you did damage to the drivers they will make noise when you use them. Like the vc rubbing. I have seen very high power change the T/S specs before though. But that is a whole different subject.

With WinISD, yes it will give you some crazy numbers. It is just giving you a starting point based off of the drivers specs. You need to play with the box size and tuning to get a design that works for you. Fwiw - many car audio subs have a qts of about .5 this makes the "ideal" size box very big. But if you use a smaller box it will give a boost to the low end and roll off slower below tuning.

Get the latest version of WinISD from their Facebook page. Try modeling your sa-8s in WinISD, put in your box design and see what you get.

Alright, thats what I did previously. But I felt like I didn't know enough about the output plots to really know what was going on. I also figured that the models would be very far off from the actual response, but I suppose using such a program gives a good guess...

It is closer for home use than in a car. there are better programs out there but they are much more difficult to use. You can have a null in a room where the subs output is canceled out by its reflection, moving the sub is a good way to check this out. (And some rooms just suck out bass) Anyway, have fun.

[Dictator 39]

i would say the room. i used to have a 10inch velodyne with 115 rms in a 11x11 room! sucker was loud. Put it in the living room ALL open from the kitchen to dining room too the hall way! could barely hear any bass.