hi i'm an old guy, got a fi q15 on an saz 1500d in my suv.

my son wants to go to sound comps, so i figured on getting another saz1500d to stap and getting a btl for the weekends.

don't need to win but want to at least be competitive enough to keep his interest and make it worth the effort

so how much difference will the average user find between the old 2 slug btl and the new 1 slug ?

and is the difference enough that i realy should be looking for a one slug.

i get that they booth are going to be crazy but on the meter does it matter that much ?

i've heard pepole say it wasn't worth upgrading but i don't own either yet .

thanks

if you don't have any experience with the old BTL, then you will not know the difference. if you do, then you will find the new BTL simply has a slightly higher ability for SPL and power handling. the new magnet structure, (which you probably would have wanted the triple stacked version of the old BTL) but still the new structure has a stronger magnetic field better concentrated on the vc. basically the new BTL has better cone control than the old version, but as far as performance is concerned it's nothing drastic and depending on setups, it's not like ppl made the swap and gained 2-3 dbs just from subs swap. I heard of a few ppl gaining db's, but it was less than 1 db....

I def. wouldn't suggest trying to track down an old version, just get the new!

Basically they are like cars, very few upgrades but usually for the better.

I def. wouldn't suggest trying to track down an old version, just get the new!

X2

i had first figured on getting a new one.

but have seen some great deals on 2slug btl's.

that got me wondering .

i had first figured on getting a new one.

but have seen some great deals on 2slug btl's.

that got me wondering .

I would go new, unless its not in your budget. Just my.02

i had first figured on getting a new one.

but have seen some great deals on 2slug btl's.

that got me wondering .

I would go new, unless its not in your budget. Just my.02

budget is not the issue, sub is actualy the cheap part of the setup.

but 2 slug btls are getting easy to find in the $200 range still working.<cheap enough to get my attention>

so i started thinking that this thing is realy for beating the snot out of on weekends.

and started weighing used with a couple recones or new without recones.

i get that the new design is stonger and better <not to mention sexier> but i have never heard either and didn't know how much better or if it was worth it.

if the new one realy is enough better i have no problem getting that.

this type of equipment is out of my league so i have to ask those of you with experience and wisdom for your help .

thanks for all your help and opinions. it realy helps.

I have the same questions. I originally wanted to get just one BTL 18" daily but now I have the opportunity to get my hands on a couple triple stack BTL 15's.

I',m just unsure of how much a difference there are between the two and if I will really hear that much of a difference. I have two Type R 12's now, but Fi is my next choice.

I think I can get 2 triple stack BTL 15's for right at the cost of a new 18 BTL. According to the seller, they were used less than 5 times in competition and have been sitting ever since. What do you all think?

Thanks and I'm looking forward to joining the Fi crew!

Also curious on this comparison. And just for shits and giggles is there any info on the magnet weights of the 2 models ?

Thanks and I'm looking forward to joining the Fi crew!

i am already a fi fan . in love with my fi q15 .

i can't beleive that it isn't comp ready , this thing shakes the heck out of my explorer.

i understand that either btl will be louder than my Q , but it is hard to grasp how much louder .

not looking for db numbers that is what we will be chasing at the comps .

but don't want to get a year into trying to gain db's and then wish that i got a new btl .

and on the same idea the difference in price from 2 slug vs 1 slug buys recones + a years worth of mdf for box testing .

so far it seems like folks with experience are recomending the new 1 slug .

i guess if i'm going to be swapping heavy boxes on weekends i should make it worth it .

and thanks everyone for opinions .

i took the advice of folks on here to steer me to the q last year , and got just what i was looking for .

Adrian- magnet weight is less on newer style than the older style with 3 slugs. newer magnet is much larger diameter around the pole piece though, which actually has more effect than a longer magnet.

OP- 2 slug models were really meant for burping, they are shorter and are not meant for as much excursion for playing music. most competitions now, bassrace and bass-boxing are playing music, therefore even if you got an older model then you would want the triple stacked with daily tinsels not the two slug setup for SPL only.

djmedik91- if the two 15" BTL's are fully loaded (built for daily use) then I would recommend two 15's over a single 18 any day. more cone area, and higher potential of power handling so potential to be louder. although I have seen a single 18 do over 170db! (wasn't a BTL, but it was a single 18)

Adrian- magnet weight is less on newer style than the older style with 3 slugs. newer magnet is much larger diameter around the pole piece though, which actually has more effect than a longer magnet.

OP- 2 slug models were really meant for burping, they are shorter and are not meant for as much excursion for playing music. most competitions now, bassrace and bass-boxing are playing music, therefore even if you got an older model then you would want the triple stacked with daily tinsels not the two slug setup for SPL only.

djmedik91- if the two 15" BTL's are fully loaded (built for daily use) then I would recommend two 15's over a single 18 any day. more cone area, and higher potential of power handling so potential to be louder. although I have seen a single 18 do over 170db! (wasn't a BTL, but it was a single 18)

The single 18" DD ?

you got it

1. 
   

OP- 2 slug models were really meant for burping, they are shorter and are not meant for as much excursion for playing music. most competitions now, bassrace and bass-boxing are playing music

thanks this is the stuff i need to know before i waste too much money.

you got it

How much power do they send to that thing to make it get numbers like that?

Have seen it in two instances. I think the guy puts like 60k on it if I remember. the other time was the kinetik world record team. on one sub with half a coil they burped like a 172. since it was only half a coil it was twice the resistance, and normal power is somewhere around 150k watts I believe. so probably like 75k. that van is a crazy build though. not really my cup of tea, but it is cool someone has done it. BTW i watched them get the world record in person, crazy watching something burp over 180 db's, that's ~ to the shuttle launch, on the launch pad! lol

How do they even power that?

Old BTL's had 3 slugs....... :-/

And Christian, they power with alot of 16volt batteries.

Old BTL's had 3 slugs....... :-/

And Christian, they power with alot of 16volt batteries.

I meant do they hook up multiple amps to one voice coil or do they just have amps that put out that much power?

Old BTL's had 3 slugs....... :-/

And Christian, they power with alot of 16volt batteries.

I meant do they hook up multiple amps to one voice coil or do they just have amps that put out that much power?

Quad coil woofers with 2 amps per coil usually, so 8 amps a sub, running LOW ohm loads like .175 per amp at 18v.

Im pretty sure its a multitude of amps, I doubt they have amps that do that much power by themselves.

Im pretty sure its a multitude of amps, I doubt they have amps that do that much power by themselves.

Yeah, that's what I was thinking. I just wanted to make sure.

it's some crazy number of stetsom 16kd's...I believe .25 ohm and yes at 18volts

Lets get this back on topic, so OP what have you decided to do (buy old if you can find one or buy new)?

I gained .7 dB with (4) 15's on 14000 watts going from 3 slug BTL's to new single

slug. Both were long coil, dual 1, and dual 1 daily gap.

If you buy the old used model, make sure you get good pictures of the tensil leads to make sure they are in good shape before you buy. The BTL's have so much excursion, people are bad about slapping the cone into the spider landing, which kills the leads.

Brian