Using a car audio subwoofer

[spwelton]

Hi all, been a lurker for a bit and decided to post up now Anyways, I've got a kinda cheapy RCA surround sound and I wanted more bass than the weak stock sub provided. I've done car audio for a while and I had a Sony 10" subwoofer sitting in my garage. I also had an old JVC 3-way box, which all the speakers in were garbage after sitting in the basement so long. They basically just made scratching sounds! So I put the Sony in the JVC box and it sounds pretty good, I'd say. It is definitely very loud!

Anyways, I've been wondering if the old JVC boxes are the most appropriate enclosure for this speaker. The JVC boxes are ported enclosures with a passive crossover inside. I've been thinking of a sealed enclosure. Unfortunately, I can't find the T/S parameters for the speaker because I don't have the model number. What is typically the best kind of enclosure for a home audio system that would be used mostly for music and gaming? I would prefer that music is especially nice on this sub, since that is mostly what I use it for, but it also needs to be able to do movies and games. Kind of a middle ground I guess.

So if any of you have any advice for a noob like me, I'd appreciate it! Also keep in mind, I'm a college student with barely any money, so this is why I'm using a car audio speaker I happened to have sitting around. So my budget pretty much covers MDF to make an enclosure and not a different driver, etc... Within the next year or so, I'll be buying a high-end receiver and making speakers for it, so I'd just like something to bridge the gap until I get a career and some $$

I'd post pics, but it says my post count is too low

 

[allargon]

If you can't find the model #, you can get measurements of the sub with subwoofer driver measuring software. I know you're a student, but I bet you can find someone in your area that has the software to measure the parameters for you.

You can post a request for that here as well as AVS, HomeTheaterSpot, etc.

Once you get the parameters, you can then design a proper box with ports/vents to get nice and loooow!

 

[lsiberian]

Hi all, been a lurker for a bit and decided to post up now Anyways, I've got a kinda cheapy RCA surround sound and I wanted more bass than the weak stock sub provided. I've done car audio for a while and I had a Sony 10" subwoofer sitting in my garage. I also had an old JVC 3-way box, which all the speakers in were garbage after sitting in the basement so long. They basically just made scratching sounds! So I put the Sony in the JVC box and it sounds pretty good, I'd say. It is definitely very loud!

Anyways, I've been wondering if the old JVC boxes are the most appropriate enclosure for this speaker. The JVC boxes are ported enclosures with a passive crossover inside. I've been thinking of a sealed enclosure. Unfortunately, I can't find the T/S parameters for the speaker because I don't have the model number. What is typically the best kind of enclosure for a home audio system that would be used mostly for music and gaming? I would prefer that music is especially nice on this sub, since that is mostly what I use it for, but it also needs to be able to do movies and games. Kind of a middle ground I guess.

So if any of you have any advice for a noob like me, I'd appreciate it! Also keep in mind, I'm a college student with barely any money, so this is why I'm using a car audio speaker I happened to have sitting around. So my budget pretty much covers MDF to make an enclosure and not a different driver, etc... Within the next year or so, I'll be buying a high-end receiver and making speakers for it, so I'd just like something to bridge the gap until I get a career and some $$

I'd post pics, but it says my post count is too low

I think in college experimenting is not only allowed it's expected. I say just experiment until you find something that works. I remember in college I did all kinds of jimmy rigging lol. phone cable is great for mounting things if you splice it. Computer power cables are great for hanging fans from loft beds lol. and enough spices can change the flavor of mac and cheese each night.

lol.

 

[spwelton]

The thing that makes me think the ported box isn't right for this sub is something I saw while playing Gear of War 2 on this surround sound system. Whenever there would be a loud rumbling (a Brumak for anyone who's played this game ), the sub would move unlike anything I've ever seen. Then again, I'm used to car audio where its mostly a clean bass guitar sound, not a rumble. The speaker was moving in and out pretty slowly sometimes, and not always symmetrically. I can't think of a better way to describe it.. It still sounded good, and I heard no bad effects. Is this normal for a home audio system? This is the only time I've ever seen a speaker do this...

 

[annunaki]

It sounds like the woofer is playing below the tuning frequency of the enclosure.

Many car audio enclosures are typically tuned to the 35hz-40hz range as they rely on the confines of the vehicle to lower the response due to transfer function.

 

[spwelton]

It sounds like the woofer is playing below the tuning frequency of the enclosure.

Many car audio enclosures are typically tuned to the 35hz-40hz range as they rely on the confines of the vehicle to lower the response due to transfer function.

That was my first impression is that the speaker was becoming unloaded at low frequencies. Would a purpose-built sealed box for that speaker (if I could find the T/S parameters) fix this?

 

[annunaki]

That was my first impression is that the speaker was becoming unloaded at low frequencies. Would a purpose-built sealed box for that speaker (if I could find the T/S parameters) fix this?

Yes, it would, assuming the sub is suitable for a sealed enclosure. If you have the T/S parameters, it will be easy to determine the most suitable enclosure for the driver.

A vented enclosure will offer more output than sealed and probably play a bit deeper (without eq) assuming it is tuned lower than the F3 of the sealed enclosure..

 

[spwelton]

So if I wanted to design a ported enclosure, I would first design the sealed enclosure and its F3 point, then choose a slightly lower F3 for the ported version and design from there?

I'm an electrical engineering major, so don't be afraid to throw gain and frequency calculations at me! (I'm used to it!)

 

[annunaki]

Actually, you would use the T/S parameters to be able to identify what the best enclosure alignment would be. The "Q" of the driver will typically give an idea of what is usually the best enclosure.

With most all drivers, vented enclosures will yield a lower f3 with applicable tuning.

 

[spwelton]

Ahh, I see, I did find a website that lists what enclosures to use with specific speakers. I'll just have to scrounge up them T/S parameters then..

Thanks

 

[annunaki]

Ahh, I see, I did find a website that lists what enclosures to use with specific speakers. I'll just have to scrounge up them T/S parameters then..

Thanks

That would be the next step. A Dayton woofer tester would also do the trick.

 

[spwelton]

In the meantime, I ordered some capacitors to put together a real simple infrasonic filter to eliminate those real low frequencies causing the problem. I'm not too worried about losing 20 Hz down, since I can't hear it anyway