Fi BTL 18 T/s parameters

[Woodlawn Cabinetry 0]

What are they since there not posted on your website?

Actually, none of the parameters for any of the BTL's are posted on your website?

Edited June 25, 2008 by Mr Cabinetry

[Cr@sh 0]

haha good luck! I have looked everywhere for the fifteen inch btl. There is UK site that sells there stuff with the parameters but from 07 models I think.

[johnecon2001 82]

The BTL is the kind of sub where T/s does next to nothing in helping you design an enclosure.

[Woodlawn Cabinetry 0]

The BTL is the kind of sub where T/s does next to nothing in helping you design an enclosure.

Well, thank you for that input, but, if ya don't mind, I still would like to know what they are, even if just as a baseline reference.

[95Honda 486]

The BTL is the kind of sub where T/s does next to nothing in helping you design an enclosure.

[johnecon2001 82]

http://www.soundsolutionsaudio.com/forum/i...showtopic=18039

[Woodlawn Cabinetry 0]

http://www.soundsolutionsaudio.com/forum/i...showtopic=18039

Well, that sucks the choad.

I tell the person asking to just wing it for the enclosure spec's.

[johnecon2001 82]

The BTL isn't like a regular sub. You can still refer to what Fi recommends in the stickies in this forum for it though.

Generally, people who buy the BTL know what to do with it box wise.. it's a pretty intense sub.

[QuestionMan 0]

I have the sub i want already, so i'm not complaining, only asking, but why do parameters not matter in the btl? Why couldn't people put it in a program, many people use btls as daily drivers, so its not like btls are only used for burps 24/7. just curious

[hayes55987 0]

The BTL is just not the kind of sub that you will be porting to so that you can even out your car frequency response or try to make it as flat as possible. If you want it to be loud lower, you build it to the recommended size and port lower. If you want it to sound louder higher notes, you build it to recommended size and port higher. If you're not sure if the BTL is right for you or not, then chances may be that you're into something a bit above your needs.

If you are trying to make it into a burp sub and want to know where to peak it, just ask around for some advice but the T/S specs really still won't do you that much good here either.

[Cr@sh 0]

The BTL isn't like a regular sub. You can still refer to what Fi recommends in the stickies in this forum for it though.

Generally, people who buy the BTL know what to do with it box wise.. it's a pretty intense sub.

But those recommendations were for the older version of btl's correct?

[weasle421 1]

They have said quite a few times that they are the same for the new BTL's as well.

[Cr@sh 0]

They have said quite a few times that they are the same for the new BTL's as well.

So there were no improvements or changes made then? Well thats a relief

[Aaron Clinton 2,372]

It seems, that going bigger and just keep pouring the power on is the approach for many BTL owners.

[NDMstang65 403]

They have said quite a few times that they are the same for the new BTL's as well.

So there were no improvements or changes made then? Well thats a relief

No, if there were no improvements or changes made then we would not have came out with the new BTL. We're not going to release a new product and spend more money on tooling to get away from the 3 slug motor if there was not a difference.

The enclosure recommendations did not change, and will not change, as there is no re-invention of the wheel here. If you notice all of our enclosure recommendations are fairly similar through out the product lineup in regards to frame size. The tolerances that we give you is what we feel is best for a daily driving scenario for our speakers. If you feel the need to be a number junkie about things, sorry. If you'll model the BTL in a box program (Parameters will be up next week) it will tell you to put it in a sealed enclosure at about 11 cubic feet to get a +/- 3dB through the spectrum of interest. This is not the case and all box programs are wrong. The woofer will NOT work in a sealed enclosure to its full potential, sorry.

Sorry if you feel that way Phil, only thing I can tell you is do what every single other person has done with our products and follow our recommendations. It's not rocket science and it is not hard to follow. Everybody else has had zero issues with following the guidelines that we have put up, I still do not see why you HAVE to have them to make a box. (as well as every single dimension of the woofer, that to this day still baffles me, in the many years i've been building boxes and fabricating things i have yet to need all the dimensions that you require to build an enclosure) We set the guidelines for a reason, because it is works best for a daily scenario, regardless of what your mind and box program might say/think.

Parameters will be up next week sometime...

Thanks

-Nick

[dbjunior 0]

there are only two specs im interested in the the bl and mms im doing a comparison between spl subs a power to weight thing. everyone knows a light powerful motor does great ported so i want to see how each sub stacks up and how it differs for sub size so far the 12 looks the most favorable

[mdexxxiv 1]

They have said quite a few times that they are the same for the new BTL's as well.

So there were no improvements or changes made then? Well thats a relief

No, if there were no improvements or changes made then we would not have came out with the new BTL. We're not going to release a new product and spend more money on tooling to get away from the 3 slug motor if there was not a difference.

The enclosure recommendations did not change, and will not change, as there is no re-invention of the wheel here. If you notice all of our enclosure recommendations are fairly similar through out the product lineup in regards to frame size. The tolerances that we give you is what we feel is best for a daily driving scenario for our speakers. If you feel the need to be a number junkie about things, sorry. If you'll model the BTL in a box program (Parameters will be up next week) it will tell you to put it in a sealed enclosure at about 11 cubic feet to get a +/- 3dB through the spectrum of interest. This is not the case and all box programs are wrong. The woofer will NOT work in a sealed enclosure to its full potential, sorry.

Sorry if you feel that way Phil, only thing I can tell you is do what every single other person has done with our products and follow our recommendations. It's not rocket science and it is not hard to follow. Everybody else has had zero issues with following the guidelines that we have put up, I still do not see why you HAVE to have them to make a box. (as well as every single dimension of the woofer, that to this day still baffles me, in the many years i've been building boxes and fabricating things i have yet to need all the dimensions that you require to build an enclosure) We set the guidelines for a reason, because it is works best for a daily scenario, regardless of what your mind and box program might say/think.

Parameters will be up next week sometime...

Thanks

-Nick

Now my question regards port size. I see there is a post indicating to add 12-16 in2 for each foot of volume. What about depth? I know with stuff like the Atomic subs all you need is a 10 inch hole for a port, no depth. What do the BTL's require? They are very forgiving for box size but the port I assume has to be precision to work right. I want to make sure this works, especially when I'm getting ready to butcher a $1000.00 sheet of lexan for a box.

[Cr@sh 0]

I would like to just see these:

Vas = Equivalent air compliance (litres)

Qts = total Q of the driver at its resonant frequency

Fs = resonance frequency of the driver (Hz)

Dv = internal diameter of port (cm)

Based on an SPL design or high frequency, not the typical 33-35 hz cenario. I am looking @ 45hz for my tuning and like the guy above before I start chopping into the 1" MDF I want to make sure of a few things.

[NDMstang65 403]

They have said quite a few times that they are the same for the new BTL's as well.

So there were no improvements or changes made then? Well thats a relief

No, if there were no improvements or changes made then we would not have came out with the new BTL. We're not going to release a new product and spend more money on tooling to get away from the 3 slug motor if there was not a difference.

The enclosure recommendations did not change, and will not change, as there is no re-invention of the wheel here. If you notice all of our enclosure recommendations are fairly similar through out the product lineup in regards to frame size. The tolerances that we give you is what we feel is best for a daily driving scenario for our speakers. If you feel the need to be a number junkie about things, sorry. If you'll model the BTL in a box program (Parameters will be up next week) it will tell you to put it in a sealed enclosure at about 11 cubic feet to get a +/- 3dB through the spectrum of interest. This is not the case and all box programs are wrong. The woofer will NOT work in a sealed enclosure to its full potential, sorry.

Sorry if you feel that way Phil, only thing I can tell you is do what every single other person has done with our products and follow our recommendations. It's not rocket science and it is not hard to follow. Everybody else has had zero issues with following the guidelines that we have put up, I still do not see why you HAVE to have them to make a box. (as well as every single dimension of the woofer, that to this day still baffles me, in the many years i've been building boxes and fabricating things i have yet to need all the dimensions that you require to build an enclosure) We set the guidelines for a reason, because it is works best for a daily scenario, regardless of what your mind and box program might say/think.

Parameters will be up next week sometime...

Thanks

-Nick

Now my question regards port size. I see there is a post indicating to add 12-16 in2 for each foot of volume. What about depth? I know with stuff like the Atomic subs all you need is a 10 inch hole for a port, no depth. What do the BTL's require? They are very forgiving for box size but the port I assume has to be precision to work right. I want to make sure this works, especially when I'm getting ready to butcher a $1000.00 sheet of lexan for a box.

The depth of the port is what you have to figure out on your own as it is different for all ranges of the enclosure spectrum for a given tuning frequency, so you say ok i have x amount of cubic feet of volume..i want to use 14sq inches of port per cubic foot...

Once you figure out surface area you put the box parameters into a program like winisd and say "I want to tune this to 32Hz" and it will give you a length of the port to be...

[johnecon2001 82]

If you really need to see T/S specs, you could always buy this http://www.partsexpress.com/pe/pshowdetl.c...FTOKEN=35944016

May give you a baseline, may be way off.

[mdexxxiv 1]

Cr@sh:

I'm not sure what driver you are using but what the CARSTEREO.COM site tells me, if you are using the BTL18 in 8 cu ft @ 45hz, is that you need a port 8" X 14" X 9.9" deep. These drivers are not spec'd and by Fi's admission most box programs don't work with their drivers. Build a slot port the width of the box and full depth with a movable side, use test tones and pull it up until it hits the note. Long ports produce low notes, shorter ports for higher notes. That will save the trouble of wasting material. As for specs, they don't mean anything for these drivers. Remember, big box+ big port= big bang.

[SEBASTO 1]

fi subs

blade ice

[johnecon2001 82]

fi subs

blade ice

Those are the old BTL parameters. Not even close to the new ones.

[Cr@sh 0]

Cr@sh:

I'm not sure what driver you are using but what the CARSTEREO.COM site tells me, if you are using the BTL18 in 8 cu ft @ 45hz, is that you need a port 8" X 14" X 9.9" deep. These drivers are not spec'd and by Fi's admission most box programs don't work with their drivers. Build a slot port the width of the box and full depth with a movable side, use test tones and pull it up until it hits the note. Long ports produce low notes, shorter ports for higher notes. That will save the trouble of wasting material. As for specs, they don't mean anything for these drivers. Remember, big box+ big port= big bang.

Im using the new 15"BTL I have 12 cubic ft to work with, 20 if I want it but easly 12 so 3 per sub. My calcs give me 30hx8wx10L on the port according to nick's suggestion of 3-5 cubic ft per sub.

[DevilDriver 28]

They have said quite a few times that they are the same for the new BTL's as well.

So there were no improvements or changes made then? Well thats a relief

This is not the case and all box programs are wrong.

Any insight on what Thiele and Small's models are doing incorrectly?