Old model BTL 18?

[Schmuck 1]

I am looking at buying 2 18" BTL and the seller says that they are fully loaded but they do not have the 3rd mag. How would this effect the performance of the subs. He says that they have 5 spiders and a fresh recone. My question is how much of an effect not having the 3rd slug has on the sub. Do they not get as loud, do they not handle the power as well? What exactly does the 3rd magnet do for the sub?

[tejcurrent 13]

If it doesn't have the 3rd slug it isn't 'loaded'.

IIRC one of the largest benefits was it coupled well with the high xmax coil giving things more room to travel. Chances are it doesn't have the high xmax coils either. Hopefully someone who understands things a bit better could chime in.

Edited July 1, 2008 by tejcurrent

[meccalli 1]

well....stacked magnets generally increase the potential (coupled with other factors)for a greater xmech and increasing the amount of air displaced.i am not too sure about its effect on the power handling..but it does not reduce it.however when magnets are stacked a net effect is "seen" as one single magnet with the "strength" of the individual slugs ..but in reality ,strength is evenly spread and actually has an effect that reduces the bl force factor of the entire structure ..which was taken into consideration of the new btl.therefore...the new design

[Schmuck 1]

So how much performance am i missing out on with just the standard BTL with cooling as opposed to the fully loaded BTL with the 3rd slug and hi xmax coil?

[meccalli 1]

well ...you will miss out on some displacement due to the lack of the extended voice coil and maybe a little power handling.....if you are talking about one without cooling..magnetic flux will be much higher and more suited for a burp scenario..however...the btl u described that you have is fine for a daily beater..hope that helps.

[Schmuck 1]

yeah these have cooling and 5 spiders from what I understand. He said that they are fully loaded but FI just forgot to add the 3rd slug. But I got in touch with FI and they said that they did not forget to add the 3rd slug that they are the standard model BTL's and could possibly have cooling. So my question is how do the standard dual slug BTL's with cooling perform for daily on 2200 RMS each?

[BKOLFO4 29]

I am going to have to ask. . . .How much for them? That would be a big part of my decision to buy them.

With 2200 watts, you should be ok with the 2 slug version if the box is designed correctly and your subsonic filter is set correctly.

IIRC, the 2 slug vs 3 slug with long coil is 16mm vs. 27mm Xmax.

Used BTL's are for sale quite often, so unless you are being offered for a smoking deal, look for the next deal with 3 slugs if you are worried about it.

Brian

[meccalli 1]

I am going to have to ask. . . .How much for them? That would be a big part of my decision to buy them.

With 2200 watts, you should be ok with the 2 slug version if the box is designed correctly and your subsonic filter is set correctly.

IIRC, the 2 slug vs 3 slug with long coil is 16mm vs. 27mm Xmax.

Used BTL's are for sale quite often, so unless you are being offered for a smoking deal, look for the next deal with 3 slugs if you are worried about it.

Brian

X2 ......exceptionally well(if the price..and conditions... are right...lol)

[Schmuck 1]

Can get the pair for $550 shipped and they have been freshly reconed.