Box Modification Spl Gains

[quakecitystudio]

what is your test cd? Also, are you going to slick the inside of the box, like a boat, somewhere on here someone said that they gained from making the inside of the box really smooth.

[sundownz]

what is your test cd? Also, are you going to slick the inside of the box, like a boat, somewhere on here someone said that they gained from making the inside of the box really smooth.

I just use sine waves on the iPod. DB Drag has an official CD that has the same thing on it.

And yes - resin work is on the to-do list.

[sundownz]

Tried a few things with no success :

No change - 155.6

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LOSS - Down 0.2 to 155.4

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This has gained me in the past... but not today, did 155.5 dB this way.

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155.5 dB again

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So no more gains yet!

[Torres]

i like this thread! i also read that rounding over the edges of the sub cutouts on the INSIDE of the box could help gain. i think i read that from nightshade...so you may already know that cuz he lives around there right? but either way i think that'd be good to see on the 'to do' list if it's not already there.

damn i wish this thread was done already lol so i know what to do and what not to do to my box. so far the only thing i planned on doing was a 45 in front of the port opening and the terminals. i'll make sure to get some good quality ones tho. possibly resin the inside as well

[bobonit]

What size threaded rod did you use?

[sundownz]

5/16" Rod - fits quite well into those Stinger ring terminals.

[sundownz]

Woops - I made a mistake earlier... must have looked at the wrong data for the subs I was using before. They are 3.0 DCR and not 3.5 DCR as I was assuming before.

With those D4 coils all in parallel I had 0.375 DCR per amp, which is more like a 0.5 ohm nominal load.

With the D1 Nightshades I built I have an actual 0.50 DCR load per amp, which is more like 0.70 ohms nominal.

Even still... it is doing 154.3 dB with a DCR much higher.

I may have to wire the amps down lower and try it that way with these coils. Or use a different amp configuration like four 1500Ds wired down to 0.25 DCR each to get a better comparison.

[sundownz]

So far the 1500s aren't much liking the 0.25 load. I can roll it and get a score but not high enough to do a GOOD score.

So I may just need to wait for 3500s and use the 0.5 DCR load for now and then build some other subs later once I get it all dialed it for the 0.375 DCR load again.

[testtones]

what if you were to try and run a 45 or radius from the bottom of your port up to the hatch? I'm not sure but it may lower your tuning a bit though

[oldschool]

Just an fyi for everybody I tried the pvc at the ends of the ports and lost .5 db also tried a 45 at backside of the port and lost an additional .1 which goes to show you every install will have different results.