Resin vs. Non-Resin test (spl results inside)

[PSturmer]

for everyone into spl i thought i would post these results

so my first test was birch vs. mdf.

box was 1.25 cubes net and it came out to be they had the same db output.

here is the thread:

http://www.caraudio.com/forum/showthread.php?t=274407



so in this test there were 2 identical box's. one had 3 layers of resin in the inside, the other did not.







results:

non resin:
~800 watts.....140.9
~2200 watts...144.1

resin:
~800 watts.....140.6
~2200 watts...144.1

i did multiple trials with the 2200 watt setup and got consistent 144.0-144.2. i did not have another dmm on hand so i was not able to see whether the reactive load changed.


it is hard to make conclusions about these results. what i learned is on small box's resin does not increase output. with larger box's resin could help just because of the fact it will add strength. on the scale my box is on, strength is not a concern.

[Canaan]

Nice post.

Just wondering, what freq. did you peak at in these tests?


I have gained a few 10ths from resin before, but that was always in 4cuft+ boxes.
Also, my note usually went up ~1hz...so that could account for the gains.

Edit:
Also, I see your #'s came up alil since the last testing you posted.
Are these test boxes the same as the other test boxes?

And, did you roll/paint on the resin...or pour it in?

[PSturmer]

Nice post.

Just wondering, what freq. did you peak at in these tests?


I have gained a few 10ths from resin before, but that was always in 4cuft+ boxes.
Also, my note usually went up ~1hz...so that could account for the gains.

Edit:
Also, I see your #'s came up alil since the last testing you posted.
Are these test boxes the same as the other test boxes?

And, did you roll/paint on the resin...or pour it in?

i played 50hz. i dont peak there though. the numbers being any higher then last tests is not significant. there are many other variables that have changed since.

[ngsm13]

it is hard to make conclusions about these results. what i learned is on small box's resin does not increase output. with larger box's resin could help just because of the fact it will add strength. on the scale my box is on, strength is not a concern.

Simple adding resin, does not add any strength what so ever.

R-tard.

nG

[mrogowski]

I was just going to post that. I believe you can get resin with fibers in it which would add strength though.

Informative post nonetheless.

[97cavy]

I just dont really understand your tests. First off, ive never seen anyone say that birtch is "louder" Its justed used to save weight and for its strength...so im not really sure where that came into the test?

And I know mulitple people who have seen gains from smoothing the interior/port opening but its much more then just resin'ing and calling it a day thinking your going to gain....

[mrogowski]

Perhaps this is the thread to post this question:

Has anyone performed SPL testing on enclosures with a highly reflective interior to see if there is a gain in output? I was chatting with someone who had aluminum tape covering the outside of his SPL box. Just curious if this would have a similar effect in the inside...

[JimJ]

In much the same way that standing waves aren't as big of an issue in subwoofer enclosures as they are in, say, bookshelf monitors, I'd think it wouldn't make as much of a difference...

Although Snoopdan had good luck with that marble port, so who knows

[ngsm13]

It all has to deal with making the interior of the box smoother, less friction... allowing the air to flow at a higher velocity...

So, whatever you use... it doesn't much matter.

nG

[mrogowski]

Ok, thanks.

[AudioXtremes]

In such a small box with a external aero resin shouldn't help much.

In a large box with a wood port smoothing it helps. My van has a few gallons.

[sundownz]

My box = needs resin... it's rough as heck

[AudioXtremes]

Drive to indy and we'll work on it Jake.

[sundownz]

Drive to indy and we'll work on it Jake.

It's not ready to drive very far yet I need to replace the rear axle seals... they are leaking grease all over my rear drum brakes so it doesn't like stopping that much *laughs*

[AudioXtremes]

Sounds exciting. My brakes in the crx went out at a drag show and I hit a truck.