Where are the best places to experiment with 45 degree corners, what sizes should i start with?

[HHR Ed]

[Kyblack76]

Titanic episode....

love me some myth busting....

you simmer down Ed

[fecupe2001]

fuck 45´s , that´s all

[mrd6]

LMAO!!! 45's help air flow hahahhahahaha

1 a box does not create air flow like water flow air does not "flow" out of your box a sub moves back and forth very violently sucking and push air example take a bottle of water that is half full and shake the shit out of it back and forth and look what is happening to the water basicaly the same as what air does in a box its not "flowing" so your better air flow argument is invalid

2 as a old hardcore compititor i have tested and built more boxes and theories than i can remeber... 45's anywhere in the box 99.9% no matter of size killed spl up to a few DBs and thats a lot

3 45's do not add strength the corner of te box is the strongest point

1) I understand that the air is moving in and out of the box, not just out. But that's the thing, it is in fact pushing and pulling in and out of the box. So any method that does in fact improve the fluid flow of air will in fact improve the efficiency of the enclosure.

2) Yes "killing SPL by a few DB's" is "a lot" but I am curious to see the proof, has anyone done a side by side test, one box with 45's and one without (with the one without being built to the same exact net volume?) Again, don't take this the wrong way, I just think it would be an interesting test for someone to do. I'm sure you know what you are talking about, but I think it is more advantageous for people on the forum to see documented proof rather than: "45's don't work, don't use them".

3) 45's will add strength to the enclosure! Don't get me wrong, bracing across the enclosure is far more effective, but adding any sort of "truss" between two structures that are at a 90 degree angle will definitely add strength.

i have done millions of test not on 2 boxes side by side but the same box no 45 did a 152.8 added a 1 45 did a 151.9 then took that 45 out and put in a differnt place did a 152.3 then added 45's to every corner did a 150.7 and that is just on the last box i was testing there were many MANY more with simalar results i just can't remeber all the numbers from 16 years of doing this stuff

if you dont want to belive it thats fine YOU TEST it! we have

Hey, its not that I don't think your right, thank you for that description of your test. But the way you did the test it seems like you built the box, and then tested it without 45's, then you added a 45, and got poor results. But by performing the test in that manner you decreased the volume within the enclosure, so isn't it not surprising that you also experienced a reduction in output?

What I want to know is if you added the 45, but also increased the enclosure volume to account for what was taken up by the 45, what would happen. I am guessing not much in a random corner, but in the case of a port corner... I still feel it would have positive results.

I may be testing this in the future!

try it out and let us know but i will tell you this i have tryed with differnt size 45's even tiny ones that would only take .001 percent of the box volume still with negative results

do you really think making a box .001 % bigger would have a differnt outcome?

Nope, I don't think it would, def agree with you there, but if the 45's were so small did they also have a negligible amount of positive effect?

I like that you are trying things for yourself, its always nicer to have first hand experience than just reading something someone else did.

On another note though, when you make your second box bigger(the one with the 45s), in which way are you going to make it larger? Add small distances in every dimension? Extend it in length only? Or hight? Or width? Maybe a combination of the three? Is the second box going to have the port the same distance form the sub? Or will it be the same distance from the loading wall? What affects are these changes going to have on the loading of the sub, standing waves, and constructive or destructive interference in internal waves?

My point is, how do you plan to make sure any gains or losses you see are from the 45s and not changes you made to the box dimensions to make the "volume" bigger. I've thought about doing the same test you are talking about, but the things I described above are just some of the reasons it seems pointless.

Let me know what you think

[CarAudioFab]

LMAO!!! 45's help air flow hahahhahahaha

1 a box does not create air flow like water flow air does not "flow" out of your box a sub moves back and forth very violently sucking and push air example take a bottle of water that is half full and shake the shit out of it back and forth and look what is happening to the water basicaly the same as what air does in a box its not "flowing" so your better air flow argument is invalid

2 as a old hardcore compititor i have tested and built more boxes and theories than i can remeber... 45's anywhere in the box 99.9% no matter of size killed spl up to a few DBs and thats a lot

3 45's do not add strength the corner of te box is the strongest point

1) I understand that the air is moving in and out of the box, not just out. But that's the thing, it is in fact pushing and pulling in and out of the box. So any method that does in fact improve the fluid flow of air will in fact improve the efficiency of the enclosure.

2) Yes "killing SPL by a few DB's" is "a lot" but I am curious to see the proof, has anyone done a side by side test, one box with 45's and one without (with the one without being built to the same exact net volume?) Again, don't take this the wrong way, I just think it would be an interesting test for someone to do. I'm sure you know what you are talking about, but I think it is more advantageous for people on the forum to see documented proof rather than: "45's don't work, don't use them".

3) 45's will add strength to the enclosure! Don't get me wrong, bracing across the enclosure is far more effective, but adding any sort of "truss" between two structures that are at a 90 degree angle will definitely add strength.

i have done millions of test not on 2 boxes side by side but the same box no 45 did a 152.8 added a 1 45 did a 151.9 then took that 45 out and put in a differnt place did a 152.3 then added 45's to every corner did a 150.7 and that is just on the last box i was testing there were many MANY more with simalar results i just can't remeber all the numbers from 16 years of doing this stuff

if you dont want to belive it thats fine YOU TEST it! we have

Hey, its not that I don't think your right, thank you for that description of your test. But the way you did the test it seems like you built the box, and then tested it without 45's, then you added a 45, and got poor results. But by performing the test in that manner you decreased the volume within the enclosure, so isn't it not surprising that you also experienced a reduction in output?

What I want to know is if you added the 45, but also increased the enclosure volume to account for what was taken up by the 45, what would happen. I am guessing not much in a random corner, but in the case of a port corner... I still feel it would have positive results.

I may be testing this in the future!

try it out and let us know but i will tell you this i have tryed with differnt size 45's even tiny ones that would only take .001 percent of the box volume still with negative results

do you really think making a box .001 % bigger would have a differnt outcome?

Nope, I don't think it would, def agree with you there, but if the 45's were so small did they also have a negligible amount of positive effect?

I like that you are trying things for yourself, its always nicer to have first hand experience than just reading something someone else did.

On another note though, when you make your second box bigger(the one with the 45s), in which way are you going to make it larger? Add small distances in every dimension? Extend it in length only? Or hight? Or width? Maybe a combination of the three? Is the second box going to have the port the same distance form the sub? Or will it be the same distance from the loading wall? What affects are these changes going to have on the loading of the sub, standing waves, and constructive or destructive interference in internal waves?

My point is, how do you plan to make sure any gains or losses you see are from the 45s and not changes you made to the box dimensions to make the "volume" bigger. I've thought about doing the same test you are talking about, but the things I described above are just some of the reasons it seems pointless.

Let me know what you think

Yes I thought about this a lot on my drive home from work and I agree. If I did find that it was "better" to have 45's I am sure there are flaws that could be determined in my test. But the explanation that was given earlier of "I made a box, metered it, then added 45's and it metered lower" as a test is not accurate. But Alpine did put it best in saying, there are a million factors affecting it.

I just think its interesting on how what is "right" will change from one forum to another, on other forums 45's are a must, but because a few people say that they are unnecessary everyone jumps on the band wagon and agrees. I just like to see some evidence. In my personal experience adding 45's has improved my enclosures, but to each their own.

[CarAudioFab]

"What I want to know is if you added the 45, but also increased the enclosure volume to account for what was taken up by the 45, what would happen. I am guessing not much in a random corner, but in the case of a port corner... I still feel it would have positive results.

I may be testing this in the future!"

You dont think thats been done,... and done.... and done.. and done..

well.. good luck with your "tests"

I'm sure its been done but has anyone documented it? Has anyone tested it in the way I mentioned above where you actually compensate for the volume the 45 takes up? I mean I'm offering to research something with my time, something that could potentially help prove something to us, and you're going to discourage me? Really?

But I mean I guess we could keep doing everything the same way we have always done it rather than trying to prove things using science, that's how the world has progressed.

Yes, I have tried as well as tons of dB Drag guys.

I tested and tested a bunch but mostly before I had a camera or YouTube channel. Heck, probably before youtube even existed.

The reason I tested was because when I was in installer school, our book on enclosures said that interior shapes did not matter as long as volume was correct. I didn't agree with this as I knew standing waves and pockets of pressure could occur inside.

So I set out to test.

As well did Terry Brocks, multi time Db Drag Champion. He had built over 100 enclosures for his CRX, and the loudest one. The one that did 159 with 4 10s was completely rectangular. No angles.

My results were the same.

What we found was that the port was the most important factor. The shape, size and length of the port was so much more important than angles or interior box shape.

It was so important that a 8.35" diameter port was over 1dB louder than a 8.5" diameter port.

Somehow I missed your post earlier, this is the type of info I am after. My main point is that adding some sort of 45 or "curve" in the port is advantageous compared to a 90 degree bend. Is this what you have found in your port experience?

[MrSkippyJ]

so it seems the question is, what exactly are we defining as improvement?

[HHR Ed]

"What I want to know is if you added the 45, but also increased the enclosure volume to account for what was taken up by the 45, what would happen. I am guessing not much in a random corner, but in the case of a port corner... I still feel it would have positive results.

I may be testing this in the future!"

You dont think thats been done,... and done.... and done.. and done..

well.. good luck with your "tests"

I'm sure its been done but has anyone documented it? Has anyone tested it in the way I mentioned above where you actually compensate for the volume the 45 takes up? I mean I'm offering to research something with my time, something that could potentially help prove something to us, and you're going to discourage me? Really?

But I mean I guess we could keep doing everything the same way we have always done it rather than trying to prove things using science, that's how the world has progressed.

Yes, I have tried as well as tons of dB Drag guys.

I tested and tested a bunch but mostly before I had a camera or YouTube channel. Heck, probably before youtube even existed.

The reason I tested was because when I was in installer school, our book on enclosures said that interior shapes did not matter as long as volume was correct. I didn't agree with this as I knew standing waves and pockets of pressure could occur inside.

So I set out to test.

As well did Terry Brocks, multi time Db Drag Champion. He had built over 100 enclosures for his CRX, and the loudest one. The one that did 159 with 4 10s was completely rectangular. No angles.

My results were the same.

What we found was that the port was the most important factor. The shape, size and length of the port was so much more important than angles or interior box shape.

It was so important that a 8.35" diameter port was over 1dB louder than a 8.5" diameter port.

Somehow I missed your post earlier, this is the type of info I am after. My main point is that adding some sort of 45 or "curve" in the port is advantageous compared to a 90 degree bend. Is this what you have found in your port experience?

In my crazy shaped test box, The woofers fired to the side, and ports fired up. I started out firing both up, then port back/woofer up. So this is a large factor as well.

But imagine 2 12s on opposite sides firing into the sides of my car. Port was firing up and justified to the rear of the box. Directly under the port was complete right angles. All 90 degrees.

The corners from the top and front of the enclosure ended up being a sharp angle, maybe 10 degrees.

Then I had a complex angle configuration on the bottom of the front to the bottom and in the corners under the woofers. Was over 10 angles in the location.

From about 2001 to 2005/2006, dB Draggers with walls were all using similar designs. Big angle behind the woofers, flat 90 behind the port.

This started changing after that to more cubical designs and scores went up in lower classes, stayed about the same in higher classes.