Need advice on spl build.

[skittlesRgood]

roll your burps and imp rise will keep the amp out of protect. do you have the stock alt in still? if so, you do not have nearly enough electrical for .5ohm. definitely need to upgrade that 4awg to 1/0awg. i mean, why restrict current? 45* along every edge is not ideal. you want them in a way to shoot air out of the port, not just throw it around and keep it out of corners. some times 45*s hurt your score. and a 45* is not a brace.

droping a class is up to you. NEVER just say "it's ok, trust me". i cant tell you how many times i have said that, or seen some one say that and they were VERY wrong. so measure the port and tell us the dimensions. if you're right, you're right. if you are wrong, we can catch it.

[outsideshot23]

roll your burps and imp rise will keep the amp out of protect. do you have the stock alt in still? if so, you do not have nearly enough electrical for .5ohm. definitely need to upgrade that 4awg to 1/0awg. i mean, why restrict current? 45* along every edge is not ideal. you want them in a way to shoot air out of the port, not just throw it around and keep it out of corners. some times 45*s hurt your score. and a 45* is not a brace.

droping a class is up to you. NEVER just say "it's ok, trust me". i cant tell you how many times i have said that, or seen some one say that and they were VERY wrong. so measure the port and tell us the dimensions. if you're right, you're right. if you are wrong, we can catch it.

^^^^^^^^^^

[IH8PunkRok]

droping a class is up to you. NEVER just say "it's ok, trust me". i cant tell you how many times i have said that, or seen some one say that and they were VERY wrong. so measure the port and tell us the dimensions. if you're right, you're right. if you are wrong, we can catch it.

very well said

[dwright27]

First, get rid of the distro block and run 1/0 from

Front battery or alternator directly to the optima in the rear. Then run your amp off the battery.

[Neo_frog]

My friend and I have been working on an spl build to take to a competition coming up. We have an Audiopipe 30001D with a 15" FI BTL. Its in a 93' mazda mx-3. The box is 5 cubes tuned at 45hz. The car peaks at 50hz. The box has 45 degree bracing's in each corner. We have 1/0 running from the battery to a distro block, then 4 gauge to an optima red top then 4 gauge to amp. We are replacing the speaker wire with either 10 or 8 gauge. We also have been told to paint the inside of the box and silicone it. The amp was run at 2 ohms and we are considering doing a half ohm burp. The length from distro block to battery is about 3 feet then another 3 feet to the amp so theres about 6 feet of four gauge. The box will be wrapped in duck tape also. We hooked it up to a termlab today and got a 146.5 in the kick panel with driver door open and sunroof open. when everything was sealed we did around a 143.8.

Questions:

Will the audiopipe handle a .5ohm burp?

Wiring the sub to .5ohm isnt a problem but how would we plug the wires into the audiopipe?

Is there anything else we can do to gain db's?

I'm sorry, but asking questions like this with the setup you've listed, don't coincide. Here's problems I see already..

Not enough information:

We need dimensions of your box and port. Most first attempts at SPL setups get this wrong. Also firing direction and orientations.

Tuned too low for an SPL setup:

You say it peaks at 50, but that's a result of your tuning. SPL setups should be higher.

Chances are, your port is too small:

See above

4 gauge wire? Really?:

Although the runs are short, you are considering a .5ohm burp. Upgrade.

Wrapping a box in "duck tape" (try to flame me):

Why did you wrap the box? Because somebody told you to?

Please help us help you. I'm not trying to be a dick, but from what I read, you're pretty confident in yourself and only want three answers that really don't apply unless we know what we're working with.

[MatthewMartin]

My friend and I have been working on an spl build to take to a competition coming up. We have an Audiopipe 30001D with a 15" FI BTL. Its in a 93' mazda mx-3. The box is 5 cubes tuned at 45hz. The car peaks at 50hz. The box has 45 degree bracing's in each corner. We have 1/0 running from the battery to a distro block, then 4 gauge to an optima red top then 4 gauge to amp. We are replacing the speaker wire with either 10 or 8 gauge. We also have been told to paint the inside of the box and silicone it. The amp was run at 2 ohms and we are considering doing a half ohm burp. The length from distro block to battery is about 3 feet then another 3 feet to the amp so theres about 6 feet of four gauge. The box will be wrapped in duck tape also. We hooked it up to a termlab today and got a 146.5 in the kick panel with driver door open and sunroof open. when everything was sealed we did around a 143.8.

Questions:

Will the audiopipe handle a .5ohm burp?

Wiring the sub to .5ohm isnt a problem but how would we plug the wires into the audiopipe?

Is there anything else we can do to gain db's?

I'm sorry, but asking questions like this with the setup you've listed, don't coincide. Here's problems I see already..

Not enough information:

We need dimensions of your box and port. Most first attempts at SPL setups get this wrong. Also firing direction and orientations.

Tuned too low for an SPL setup:

You say it peaks at 50, but that's a result of your tuning. SPL setups should be higher.

Chances are, your port is too small:

See above

4 gauge wire? Really?:

Although the runs are short, you are considering a .5ohm burp. Upgrade.

Wrapping a box in "duck tape" (try to flame me):

Why did you wrap the box? Because somebody told you to?

Please help us help you. I'm not trying to be a dick, but from what I read, you're pretty confident in yourself and only want three answers that really don't apply unless we know what we're working with.

I'll try to answer your questions the best I can, then further explain our situation in more detail.

We need dimensions of your box and port. Most first attempts at SPL setups get this wrong. Also firing direction and orientations.

Box is 5 cubes. 45hz. The internal height is 16.25 inches. The port is 5 inches wide. Port area then comes out to be 81.25 sqin. This equals 16.25 sqin of port/cuft.

The sub faces up, and the port sideways. The box is a very tight fit in the cargo area of the mx-3. There is no space between the back and front walls. There is a recessed pocket of space that the port fires into. The same pocket on the opposite side houses the optima redtop.

Tuned too low for an SPL setup:

You say it peaks at 50, but that's a result of your tuning. SPL setups should be higher.

The car's peak frequency was found using a sealed box, not the result of any tuning. Ideally, the sealed box would have taken up the same amount of space in the cargo area as my SPL box, but that wasn't the case. This probably threw off the "true" peak freq. for the car. To what extent is another story.

Chances are, your port is too small:

Possibly. When I designing, I was under the impression that the bigger the box, the more efficient it becomes. Because of this, I put net cuft. first, and port area second. The idea was to use up as much volume as possible. The result of this is 16.25 sqin. of port per cuft.

On a related note, our local installer said we should have used a smaller box. This surprises me since the response curve on winisd shows more output with a larger box.

4 gauge wire? Really?:

Although the runs are short, you are considering a .5ohm burp. Upgrade.

Agreed. We weren't considering burping at .5 ohms until just recently. If the electrical can't handle it, we will make due with what we have now. Theoretically, the 3000d puts out 3000w at 2 ohms and the 1500d puts out 3000w at .5 ohms. What is the difference in 3000w at 2 ohms vs. .5 ohms? Keep in mind we had no problems running the 3000d at 2 ohms.

Wrapping a box in "duck tape" (try to flame me):

Why did you wrap the box? Because somebody told you to?

Yes. That's exactly what we did. We wrapped the box in duct tape under the advice of a local stereo shop installer who said that he's seen dB gains everytime.

In no way do I want the answers I expect. I'm probably way off in some aspects of this build, but that's OK as long as I can learn from my mistakes.

roll your burps and imp rise will keep the amp out of protect. do you have the stock alt in still? if so, you do not have nearly enough electrical for .5ohm. definitely need to upgrade that 4awg to 1/0awg. i mean, why restrict current? 45* along every edge is not ideal. you want them in a way to shoot air out of the port, not just throw it around and keep it out of corners. some times 45*s hurt your score. and a 45* is not a brace.

droping a class is up to you. NEVER just say "it's ok, trust me". i cant tell you how many times i have said that, or seen some one say that and they were VERY wrong. so measure the port and tell us the dimensions. if you're right, you're right. if you are wrong, we can catch it.

Based on the design above, where would you place the 45s?

Edited May 12, 2011 by MatthewMartin

[dwright27]

Build, test, test, test, and test some more. Repeat as many times as possible