Sundown SA 18s

[Justin braaapp]

I'd get one yardsale or used. Because they are only 2.5" coil, they get loud on less power.
Send 1k clamped to an SA 18 and Fi SP4 18. Then tell me which one is louder

This is a good point. My sp4 on a nendo 3500 wanted way more power to get to its full potential but when I put an ab vfl 12 on the same amp with the gains backed down the 12 was reaching mechanical limits and getting surprisingly louder to the ear than the sp4 but the sp4 did just crush it on low end. But basically I agree with adulbrich that 2.5 coils will take less power to get loud than a bigger coil would. I wouldn't hesitate on the sa's man they are stout subs, heard one sa 15 in a trunk on 1000 wrms and that thing was getting down and loved the power

 

[adulbrich 5,000+ posts]

This is a good point. My sp4 on a nendo 3500 wanted way more power to get to its full potential but when I put an ab vfl 12 on the same amp with the gains backed down the 12 was reaching mechanical limits and getting surprisingly louder to the ear than the sp4 but the sp4 did just crush it on low end. But basically I agree with adulbrich that 2.5 coils will take less power to get loud than a bigger coil would. I wouldn't hesitate on the sa's man they are stout subs, heard one sa 15 in a trunk on 1000 wrms and that thing was getting down and loved the power

I've got an SP4 coming in the mail, was supposed to ship today. What was yours wired to on the 3500? Could it take more mechanically? I was thinking I'd do .5 on my M4a for burps

 

[massivespl]

and ive been in the 156s with 2 3" coiled woofers. you dont need 16k watts to be loud. efficiency is where its at (and honestly, the woofers I used weren't even terribly efficient).
more efficient driver= less power needed. less power needed= less heat. less heat= less coil needed.

look, I'm not downing your audio choices, I'm legitimately glad you're happy. however, you cannot logically argue that its not a better idea to have a more efficient setup, all things being equal.

I can say with 1000% certainty, im happier with my current setup than I EVER was with any of my 4" coil drivers. (2 18" tc 5200s, 2 18" tc lms, 2 15" ss xxx).

of course, time could account for a change in taste.

I never once said anything about efficiency. I'm talking about handling heat better. And in the burp vids of te SA 18 isn't Jacob throwing 8k at one for a 157 or whatever? Is 8k efficient?

 

[Justin braaapp]

Bigger coil will handle heat better that's a fact unless ur comparing some really cheap coils to some very high end coils.I've had 4 4" coil woofers wired to .5ohm on a crossfire 8k and hardly got really warm, then went to 4 SA 18s and wired to 1ohm and they would get hot fast on lower note songs and would get stinky after a song full tilt... But now I have 2 3" coil nsv3 18s on a crossfire 8k at .5ohm and those mofo eat up the power and bang all day long. This is just personal experience I've had. So take it for what you will.

You had them on about 4 times rated power that's the only reason haha I would expect them to get hot at that power. However for the power OP has it would probably be ideal to go with the sa's. Either way that system sounds like it was nasty man!

 

[Justin braaapp]

I've got an SP4 coming in the mail, was supposed to ship today. What was yours wired to on the 3500? Could it take more mechanically? I was thinking I'd do .5 on my M4a for burps

Mine was wired at 1 ohm on the 3500 and it really wanted more to reach its full potential which I didn't like because at the time I was broke lol. I did burn up the tinsel leads on the power I had it on though so hopefully they fixed that issue because I never even pushed that thing into clipping or ran it on low voltage so just food for thought. Don't get me wrong though that sp4 was stupid nasty on lower end and just tore apart my truck but it still wanted more haha

 

[adulbrich 5,000+ posts]

Mine was wired at 1 ohm on the 3500 and it really wanted more to reach its full potential which I didn't like because at the time I was broke lol. I did burn up the tinsel leads on the power I had it on though so hopefully they fixed that issue because I never even pushed that thing into clipping or ran it on low voltage so just food for thought. Don't get me wrong though that sp4 was stupid nasty on lower end and just tore apart my truck but it still wanted more haha

Alright, cool. Thanks!

 

[Justin braaapp]

Alright, cool. Thanks!

No problem brotha

 

[Justin braaapp]

Alright, cool. Thanks!

not to derail this thread but I wanted to ask you how you liked your x-10? Im going to be putting my two zv4 15's is this weekend and was just wondering how that x treated you

 

[adulbrich 5,000+ posts]

not to derail this thread but I wanted to ask you how you liked your x-10? Im going to be putting my two zv4 15's is this weekend and was just wondering how that x treated you

I ran it infinite baffle, so that is way different than other installs. I'm assuming you're going ported, so my opinion isn't really fair. It sounded great, but was not nearly loud enough for me. Just kind of complimented the music. One 10" in IB is way different than some 15's ported. You should be happy

 

[Justin braaapp]

I ran it infinite baffle, so that is way different than other installs. I'm assuming you're going ported, so my opinion isn't really fair. It sounded great, but was not nearly loud enough for me. Just kind of complimented the music. One 10" in IB is way different than some 15's ported. You should be happy

Oh dang didn't know you did IB, Thanks for the input though man!

 

[adulbrich 5,000+ posts]

Oh dang didn't know you did IB, Thanks for the input though man!

No problem! I'm running my custom N3's IB, so hopefully things work out this time.

 

[Justin braaapp]

No problem! I'm running my custom N3's IB, so hopefully things work out this time.

Do a build thread for sure!

 

[adulbrich 5,000+ posts]

Do a build thread for sure!

It's in my sig, lol. I'm actually about to go outside and do some work right now

 

[sundownz Pro Seller]

I never once said anything about efficiency. I'm talking about handling heat better. And in the burp vids of te SA 18 isn't Jacob throwing 8k at one for a 157 or whatever? Is 8k efficient?

Indeed -- absolute thermal performance is *generally* increased with a bigger coil -- all else being equal. In my particular example earlier -- a 3" coil performed worse than a 2.5" because some cooling features were removed (otherwise motor venting was identical).

For the SA-18 I started out with a desired compliance (that is soft enough to work well with 600-watts but stiff enough to take some abuse) -- and in order to achieve the desired level of excursion needed a certain coil length -- so that lead me to the voice coil. A 3" aluminum coil is too light and a 3" copper coil is too heavy to meet my first goal -- it would need to be too soft with the AL coil and too stiff with the CU coil in 3" to achieve the FS level I wanted (and this compliance being too low or high). A 2.5" copper coil is just right to hit the performance goal I had in mind.

So for a driver designed for 600-1,000 watts jumping a coil size often offers no benefit and can actually hurt the overall performance of the driver. So for this application, and thus this thread, the fixation on coil size is really misplaced.

Now -- in your case with that much power -- an SA-18 is obviously not going to take the place of a big nasty driver like the NS v.3 by any means.

---

As far as the SPL scores -- it was actually quite efficient up to the lower 150s. Takes quite a bit to hit that 154 legal / 158 kick score -- the SA, of course, beings to run out of steam //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

For reference, though, we dropped a DD 9518H-SC in there and only gained a few tenths at our power level (battery limited).

 

[adulbrich 5,000+ posts]

The 9500 series can take quite a bit of power too, but again, it's only rated at 1500 RMS. Not too surprised gains weren't significant.