4 inch four layer coil versus 3 in 8 layer coil?

A 4" coil typically has superior cooling capacity. You'd need something like the nightshade's super long 4 layer 3" coil in order to begin matching heat dissipation. The super long 3" coils can get the heat dissipation of a 4" coil or close to it, but you wind up losing a lot of efficiency, because a lot of the coil isn't in the strongest gauss part of the motor, sacrifice you make for a super long coil. A 4" coil will typically have more of the coil itself centered in the gauss of the motor.

4" is about twice the circumference of 3", so a 4" coil is usually going to weigh a ton more.

So as far as high powered stuff goes:

3" 8 layer woofer: lower Mms, higher Fs, more efficiency, less inherent heat dissipation.

4" 4 layer coil: typically very high Mms, sometimes low or unusually low Fs (good for high power music), super good heat dissipation.

So my overall general statement, as I design for many 3 and 4 inch coiled woofers, is that now days, if you want to score loudly and be more efficient and accurate, do the 3" coil. If you want a more low end daily that'll take ungodly amounts of power, then do the 4" coil.

Depends on the woofer, about 2000-2500 w RMS is where I would start looking at 4" coils over 3", considering ferrite motors only. 3" coiled neo's might be the best overall coil and motor combination that exists for car audio.

4" coiled woofers tend to naturally have big Xmax inherently, I think it has to do with most 4" coiled woofers have 10" spider packs or larger spiders than 3" coiled woofers, and they get that Xmax while using the motor strength well, maybe unlike some of Sundown's super long 3" coils. Not hating, I really like their woofers, but I highly suspect the efficiency issues people have with those woofers are because of the super long coils are limited with how much of the coil can actually be inside of the usable gauss of the motor at any given time, because it's a smaller, concentrated area.
 
If you're gonna run 3000+ watts, I would either do a neo 3" or a 4" ferrite for sure.

If you're gonna run 2kw, you could do a lot of different 3" ferrite motor woofers. I still think at 2500w I would opt for a 4" coiled woofer for daily, personally.
 
If you're gonna run 3000+ watts, I would either do a neo 3" or a 4" ferrite for sure.

If you're gonna run 2kw, you could do a lot of different 3" ferrite motor woofers. I still think at 2500w I would opt for a 4" coiled woofer for daily, personally.
What would be the advantage of the 5 inch coil Morel uses in their subs? They don’t typically have high power handling. Would that give the Morel an SQ advantage?
 
How about a 7.4" coil
Parts Express has a 15 with 7.4x2.25 with 3500 watt rms
I seriously debated on ordering one for future considerations but the dual 8 ohm VC changed my mind along with the sealed enclosure recommendation
 
If you're gonna run 3000+ watts, I would either do a neo 3" or a 4" ferrite for sure.

If you're gonna run 2kw, you could do a lot of different 3" ferrite motor woofers. I still think at 2500w I would opt for a 4" coiled woofer for daily, personally.
That makes sense to me. I was wanting to run right at 3K. If I run a single 21 in 8.5 cubes it should be the 4-in coil but I'm thinking 215s with 3 inch neo coils sounds like the best option for me if it means better efficiency accuracy and heat dissipation.
 
I've had some monster 4" coil subs. I stick with 3" now... giggity.
I'm just so tempted to run a single big 21 with a 4-in coil because I've always had multiple sub setups.
The fi neo version of the omega/delta 4-in 4.11 looks interesting.
Has options to upgrade to the plus coil extra Gap and extra spider as well. Good BL and would do well in a low-tuned big box I bet. With the heavy coil option I could probably run 5k to it.
 
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5 inch coil Morel
I would imagine that is going to look more like a PA coil than the beefy stuff you'd find in DD 99XX, DC LV6, or various "team" woofers.

As far as the information I have got from very reliable source and my own experience 3" 8 layer will hold more heat than 4" 4 layer but 4 layer may be more efficient all things equal because you start to need a very wide gap to fit those thick coils. I like TC 4hp variants, LV6 DC, and DD 99XX for 4" coil subs. The American Bass and Soundqubed 4" coil models are pretty solid if you're not into spending big.

If you're looking into Neo, check out Pierce Audio. They have neo lineup and I've had good luck with their parts in the past and their motors I've seen around performed quite well. I think they also make some huge cones.
 
For the 21" neo sub you are looking at there isn't really much downside to going with a 4 inch coil. The motor force on a neo is usually pretty damn high and a shorter wind 4" coil will give you alot more efficiency than a taller 3" coil.

I'm probably a bit biased, but I've ran 2", 3", and 4" motors, 3" and 4" neo. For a low power daily, a 2 inch sub built on a TI frame will work wonders. Once you start getting into the 1k power range a 3" coil helps a ton with reliability. Getting closer to 2k and the 4" coil starts to make more and more sense.

I'm only throwing 1200w at my 4" coil neo right now. I know the coil can handle double that. Besides the bragging rights, the only real reasons to go Neo are weight savings and efficiency. Personally, I love efficiency.

Matt
 
For the 21" neo sub you are looking at there isn't really much downside to going with a 4 inch coil. The motor force on a neo is usually pretty damn high and a shorter wind 4" coil will give you alot more efficiency than a taller 3" coil.

I'm probably a bit biased, but I've ran 2", 3", and 4" motors, 3" and 4" neo. For a low power daily, a 2 inch sub built on a TI frame will work wonders. Once you start getting into the 1k power range a 3" coil helps a ton with reliability. Getting closer to 2k and the 4" coil starts to make more and more sense.

I'm only throwing 1200w at my 4" coil neo right now. I know the coil can handle double that. Besides the bragging rights, the only real reasons to go Neo are weight savings and efficiency. Personally, I love efficiency.

Matt
Yeah I'm willing to spend a little more to save weight and have better efficiency that's exactly what I want.
 
I would imagine that is going to look more like a PA coil than the beefy stuff you'd find in DD 99XX, DC LV6, or various "team" woofers.

As far as the information I have got from very reliable source and my own experience 3" 8 layer will hold more heat than 4" 4 layer but 4 layer may be more efficient all things equal because you start to need a very wide gap to fit those thick coils. I like TC 4hp variants, LV6 DC, and DD 99XX for 4" coil subs. The American Bass and Soundqubed 4" coil models are pretty solid if you're not into spending big.

If you're looking into Neo, check out Pierce Audio. They have neo lineup and I've had good luck with their parts in the past and their motors I've seen around performed quite well. I think they also make some huge cones.
I know the 3-in 8 layer incriminator audio judge and Warden are pretty damn impressive as well
 
I would imagine that is going to look more like a PA coil than the beefy stuff you'd find in DD 99XX, DC LV6, or various "team" woofers.

As far as the information I have got from very reliable source and my own experience 3" 8 layer will hold more heat than 4" 4 layer but 4 layer may be more efficient all things equal because you start to need a very wide gap to fit those thick coils. I like TC 4hp variants, LV6 DC, and DD 99XX for 4" coil subs. The American Bass and Soundqubed 4" coil models are pretty solid if you're not into spending big.

If you're looking into Neo, check out Pierce Audio. They have neo lineup and I've had good luck with their parts in the past and their motors I've seen around performed quite well. I think they also make some huge cones.
Wow the pierce audio stuff looks good
 
If you're gonna run 3000+ watts, I would either do a neo 3" or a 4" ferrite for sure.

If you're gonna run 2kw, you could do a lot of different 3" ferrite motor woofers. I still think at 2500w I would opt for a 4" coiled woofer for daily, personally.
So you think if I go with a single 4-in coil sub for daily it should be ferrite for sure?
I'm willing to go that route because still would be saving weight if I went with a single large sub at ~80 lbs that could take 3 to 5K. In the SUV I'm getting I'll have space to build up the 60hz and up range so I would like that digging low shaking ability of a low tuned big coil sub.
 
I would imagine that is going to look more like a PA coil than the beefy stuff you'd find in DD 99XX, DC LV6, or various "team" woofers.

As far as the information I have got from very reliable source and my own experience 3" 8 layer will hold more heat than 4" 4 layer but 4 layer may be more efficient all things equal because you start to need a very wide gap to fit those thick coils. I like TC 4hp variants, LV6 DC, and DD 99XX for 4" coil subs. The American Bass and Soundqubed 4" coil models are pretty solid if you're not into spending big.

If you're looking into Neo, check out Pierce Audio. They have neo lineup and I've had good luck with their parts in the past and their motors I've seen around performed quite well. I think they also make some huge cones.

Yeah, I'm talking about non pro audio subs. There are big coiled pro audio subs that are more IB like, it's a totally different design than like a DD or Fi with a 4" coil.
 
I would do 2 15's.
While I'm definitely fascinated with a single big sub big coil setup, I'm going to take your advice and go with 2 15s. The three inch coils and neo motors do look good, and I can definitely see how it would dissipate heat better and be more accurate for music.
Say I wanted to keep my subwoofer weight at 80 lb Max what are some good neo 3-in coil subs that can handle 1500 to 2K that weigh 40 lb or less? Lightweight and smaller box requirements are definitely my best friends!
 
Idk what the Fi SSD calls for but they should be taking orders soon as they said end of June or July. Those are beefy subwoofer and the rms is 1,500 watts. Plus Fi subwoofers are known to take more.


These can work in any design and they have a few options from the 3.5 up to the 3.9. Yeah the wait ***** but you would be happy with a Fi Subwoofer.

 
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