Debating a recone for my RE 18HC D2. Looking for some insight.

[chuey_316]

I've had this sub for awhile now, and it still works great. Have been debating lately about buying a FI recone kit for it, for when it's time. When the time comes to recone, I'll want it louder, obviously, but equal or better sq wise. Also would like higher power handling.

After some googling, I've been checking out the BTL N2, but not sure if it's the right choice. I've been seeing mixed results on reconing the hc. Some say that flat wind coils will work, others say no. Also, some say that the hc motor can only handle 1600-1700w, while others say 2000-2500 daily is no problem. Just looking for some input as to a good choice.

For a little more info, I run ported in a blazer, Between 32-36hz depending on box. I listen to rock/rap, but lean more towards rap in the truck. Amp at the moment is a Belva BB5000D.

[audiofanaticz]

From what I recall they are rated for 1500rms, and they could probably handle around 2000 rms.
Its impossible to recone a woofer and give it a higher power handling. You can put a stronger coil in it, add extra spiders, etc.
But if the motor does not have the cooling vents/chamfer to keep the stronger coil cool then all that will happen is the coil will get hotter than it should and possibly blow.

I cant remember for the life of me if they have cooling chamfers around the pole piece or not, but I do remember that they do have a vented pole.

Flatwind coil or traditional round wire, it doesnt matter much since typically either coil can be made to fit the gap. Fi offers either or, so they should fit reguardless of what people say.

Scott the owner of Fi Audio and Ascendant Audio use to be the guy behind the R&D of the old RE subs, so he should know what he can put in there, especially if they are his woofer designs, and is offering recones for them.
Aluminum flatwind coils will handle more power and cool better, a round wire coil is typically copper and will give the woofer a higher BL and a higher mass, and usually handle less power for extended periods of time.

Believe me those amps are not efficient at all, their 3000 model takes 200amps to make 1300 wrms.

I use to have a video where someone had the bb5000 on an Amp Dyno and I saved it before the user deleted it, but cant find it currently it was some pretty low numbers...

[audiofanaticz]

Ok had to load my other hard drive in to the computer and found the video.

So if you are having problems with the woofer handling power, you are most likely clipping it, and it is getting hot and stinky because that amp really doesnt make enough power cleanly to feed that sub its rated rms power. So if you want that woofer to get louder your best option would be to get a new stronger better amp.

Here are screen caps of the video when it was tested at 1ohm certified, 1ohm to uncertified to clipping, and 1ohm dynamic burst on the ad-1.

1718 watts rms at 1 ohm certified at 1% THD

2091 watts rms at 1ohm uncertified to clipping

2238 watts rms at 1ohm dynamic burst

1718 watts rms at 1 ohm certified at 1% THD

2091 watts rms at 1ohm uncertified to clipping

2238 watts rms at 1ohm dynamic burst

I hope that is good enough insight for you.

[chuey_316]

Thank you. That's exactly what I was looking for. Given that the power handling will be the same, any ideas on which recone should get louder than the hc, and still sound good?

I know that the amp isn't a 5k, or even the 3k that they claim. I figured it was around 1800w before clipping, so the result of 1718w @ 12.10v is right near what I expected. At full tilt, my voltage stays up around 13.5-13.75v. Not sure if it's a regulated power supply or not, so maybe getting a bit more watts, idk. Either way, I'm happy for the $100 I paid for it.

No problem with the hc's power handling. It's rated at 1200w, and doesn't smell when pushed unless it's played under tuning freq.

[audiofanaticz]

Either recone you get wont really be louder, Honestly after reconing it will most likely be somewhat quieter than it was before until the spiders loosen up.
If you want it louder get a bigger amp that puts out more power, or a new box one that is maybe slightly larger and/or more port area.

[chuey_316]

Gotcha. I thought that maybe one recone may have more xmax, and move more air, ect... In that case, I'll just keep it how it is. Don't really wanna get a bigger amp. Subs only rated at 1200w. Now another box for sure. Planning on another build in the spring. Box right now is 7.74 cu.ft, 90.75sq", tuned at 33.7hz. Deciding if I wanna go around 8.5 cube like I had in my other truck, another abc, or pay someone to design a 4th or 6th order.

[audiofanaticz]

You can put a cone with a huge surround on a woofer and larger diameter spiders but you will need to get a new basket that will support the larger spider and additional xmax (something like a Ti basket).
But then the direct drop in recone parts from Fi will not fit and would have to be a custom build up.

Still at the end of the day you will still be limited to the motors strength and size.

If you put a different coil with a longer winding height in an attempt for more xmax chances are if the motor does not have the clearance for the moving assembly on the back stroke the coil will slam against the back plate and damage the coil.

So really you would need to tear down the woofer and get all the gap measurements and go from there to see what can be done, or even worth doing.

More then likely the recones that Fi sells for the sub are going to be slightly updated to what you have, but overall the performance will be the same once the woofers suspension is loosened up.

[chuey_316]

I learn something new everyday. Thank you, I appreciate the help.