2.5" Voice coils or 3"?

[DonH 5,000+ posts]

no problems with a 2.5" or 3" coil. like stated its all a culmination of soft parts. spiders, and weight of the cone, stiffness of the surround etc. all play a very important role in the sound reproduction of a driver.

 

[DonH 5,000+ posts]

[quote name='mclerico83']i would get 2 xfl's from @mylows10 ;

and a box from @double 07 ; be very happy and loud for under 600 bucks lol[/QUOTE]



i wouldnt get those subwoofers if someone held a gun to my head, the box tho thats a good choice. no disrespect to mylows, I am just not impressed by any american bass drivers outputs.

 

[mylows10 5,000+ posts]

well he could get dc subs too,which would be my first choice

 

[AndrewHD 10+ year member]

Thanks guys, I am now looking for 2 12's with softer parts and lower power handling than the BTL. My goal is not all out SPL anymore (already removed the second battery but still have big 3 and HO alternator). I would like it to sound good but be loud at all volume levels. I just didn't like how I needed to crank the volume to get the most out of the BTL. I am thinking of getting the SA 12's ported to 30hz in 3.75-4.0 cubic feet on around 1,500 watts @4ohms. By the way I was running the BTL on a Sundown SAZ 2500 at 1 ohm with dual batteries. Just looking to downgrade the power but still have plenty of air movement. Is this a good idea?

 

[mclerico83 5,000+ posts]

Dc is nice. I would also look at some ssd from fi.

 

[*Ace* 10+ year member]

Isn't this always a problem with low qts subs? They need excessive power to play loudly.


Well if you don't have to give more power to the sub with the softer suspension to get the same SPL as the "SPL" driver' date=' then why do "SPL" drivers even exist? The hell's the point????

Isn't the goal to get as much SPL as possible with the least amount of power?[/quote']

Try giving a sub with an extremely soft suspension 5000 watts rms for a burp and see if the spider tears, coil bottoms out, etc. SPL subs use stiff suspensions for mechanical power handling.

So in SPL subs you want to aim for low MMS and high BL for efficiency, and also stiff spiders for mechanical power handling when dealing with extreme power levels.

 

[hispls 5,000+ posts]

Hey guys just need a little help understanding the differences between the two voice coil diameters. When I had 3" coils on my BTL the sub would require massive amounts of power to get moving. I was wondering if I stepped down to a sub with 2.5" coils would it require less power to get moving?

Coil power handling is roughly 100W per layer multiplied by the diameter (in inches). This can vary of course, but a decent rule of thumb.

BTL takes a lot of power to get moving because the suspension is stiff enough to stand on also. If you have limited power on tap an SPL sub that's designed to take 2000W + is likely not going to be your best solution and they'll almost never be terribly musical.

I'd say if you have the Sundown 2500 you don't want to mess with 2.5" coil sub unless you're using a pair of them and even then you'll be pushing it.

I suspect you might get more go out of that sub if you just re-cone it with a softer suspension.

 

[VWBobby 10+ year member]

What you are talking about is efficiency. The more efficient the sub is, the less power it needs for the same output to the point of distortion. I'm glad you are choosing this route over more power and less efficient subs. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

A SPL sub is designed to put out the most SPL at the specified tuning range or peak of the box and vehicle cabin. A stiff SPL sub will usually peak out a lot higher (55-65 hz range) than a sub that is designed more for SQL or SQ. For this reason, a stiff suspension SPL sub needs a heavy 3" or 4" coil and more power to overcome the restriction of the spider and surround (QTS).

I would rather take 2 efficient subs at 1500-2000 watts that can play flat from 20hz to 65hz than 1 inefficient sub with 2000-4000 watts that will peak around 55-65hz and not sound very good at any other range.

 

[AndrewHD 10+ year member]

What you are talking about is efficiency. The more efficient the sub is, the less power it needs for the same output to the point of distortion. I'm glad you are choosing this route over more power and less efficient subs. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif
A SPL sub is designed to put out the most SPL at the specified tuning range or peak of the box and vehicle cabin. A stiff SPL sub will usually peak out a lot higher (55-65 hz range) than a sub that is designed more for SQL or SQ. For this reason, a stiff suspension SPL sub needs a heavy 3" or 4" coil and more power to overcome the restriction of the spider and surround (QTS).

I would rather take 2 efficient subs at 1500-2000 watts that can play flat from 20hz to 65hz than 1 inefficient sub with 2000-4000 watts that will peak around 55-65hz and not sound very good at any other range.

Thanks for your reply. I had my 15" BTL tuned at 35hz and once at 30hz and while it did get very loud, I knew it has more potential. But in my trunk car I believe 2 12's would move more air (not concerned with the numbers on the meter) while sounding better.

 

[mlstrass 5,000+ posts]

You could get a recone for the BTL with diff soft parts, ones that are more friendly for a daily set up.