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MikeMartel

Fi BTL 18" N2 Box

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Why would you not get an amp to do power at 2 or 1 ohms? Why strain the electricals, sub, and amp more by running it at .5 ohms? That's stupid. For comps for a burp or two is fine but if you don't know what you're doing, don't do it.

Also, I think OP should have gotten a 15 but if you bought it already, sorry. I guess you can make it work.

That's always been how I think. Just because an amp goes down further doesn't make it better for some reason. I'm in the process of looking a new amp for my dual .7 btl, and it's either going to do power at 2 ohm, or I'll get two smaller amps and strap them at 2 ohms.

get the audiopipe ap30001, does 3k at 2 ohms.

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Why would you not get an amp to do power at 2 or 1 ohms? Why strain the electricals, sub, and amp more by running it at .5 ohms? That's stupid. For comps for a burp or two is fine but if you don't know what you're doing, don't do it.

Also, I think OP should have gotten a 15 but if you bought it already, sorry. I guess you can make it work.

That's always been how I think. Just because an amp goes down further doesn't make it better for some reason. I'm in the process of looking a new amp for my dual .7 btl, and it's either going to do power at 2 ohm, or I'll get two smaller amps and strap them at 2 ohms.

get the audiopipe ap30001, does 3k at 2 ohms.

That is an option, I'm just taking my sweet time looking around because my friend is kind enough to let me borrow his 2 ab vfl100.1's whenever I need to demo, or slam on the weekend when I'm home from college.

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Explains why they have the Cresendo 3K at .5 ohms?

Smooth.

-_-"

Jeeze, such a smart guy

It is called not knowing any better, and simply being a lemming and doing exactly what the manufacturer that really makes them says. It's simply not understanding how an amplifier works..in conjunction with a speaker.

When you start to drop an amp below 1ohm more heat is being built up because the power supply and output portion of things of the amplifier simply cannot handle the demand that the output stage is wanting to get. When you do not have a subsonic filter...or one that is set improperly...you then start to make this thing that you've just microwaved move...

You are slamming the gates open/closed on the output transistors at 90+% duty cycle, which is absolutely asinine and they freak out.

Take a can of coke, pop the top open and bend it back and forth a few millimeters...within it's mechanical limitations that tab will never break. Now if you start to bend it past its mechanical limitations is when you start to get into trouble. This is where the subsonic filter comes in and making sure that you are not playing full power below port tuning frequency of a sub. If you already have something that's hot from running it hard on one of the Korean amps and you start yanking the soft parts past their mechanical limitations more and more heat builds up...

You get to the point where so much heat builds up that the spiders start smoldering...they won't catch on fire until you've clipped the signal to death, vaporized all of the flame retardant spray that the spiders are soaked in and then it smokes. (square wave form, dc voltage out of the amp because the power supply cannot handle what you are doing to it)

It's not the sub, there is absolutely nothing wrong with running those leads like they are. What's going on is an issue of the big cheap Korean amplifiers in and of themselves...and total ill-regard to what a microwave and conductive material does.

Hope this helps you understand...if you run a Crown A6000Gti you'll never have a problem...because it's an A/B amp....the other stuff that is cheap...don't run it below 1ohm or you are going to have nothing but problems because in order to get that big power cheaply and cut out on the parts that are going into the amplifier the switching frequency of the power supply must be ramped way up...in turn microwaving woofer parts.

:orly3::WTFBubble:

Yes, that is true, I think, that little which amp can work on on .5 ohm, daily. I think if you have a daily sub in daily(big) box, you have a very big box impedance rise, which mean that if you want more efficiency from amp ( :morepower1: without clipping, buy sub with dual 1 ohm wire and wire down to .5 ohm, because in real life you got 2ohm impedance or more, thats the point of this quote.

I don't know for woofer box without impedance rise. ^_^

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Back to the woofer size, you can't always make an 18 fit. I agree with whomever said you should go for a 15, saves you a lot of headache especially if you have limited box building experience. That being said, you can be as creative as you want with angled baffles and such, just don't over extend yourself and end up regretting you ever started.

I can relate, as my trunk is huge but oddly shaped (Chrysler lhs) allowing only 14" of clearance where I want the sub to sit.

Didn't stop me from getting a 15 in there149289_575112188576_17506340_33040577_2129527_n.jpg

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Explains why they have the Cresendo 3K at .5 ohms?

Smooth.

-_-"

Jeeze, such a smart guy

It is called not knowing any better, and simply being a lemming and doing exactly what the manufacturer that really makes them says. It's simply not understanding how an amplifier works..in conjunction with a speaker.

When you start to drop an amp below 1ohm more heat is being built up because the power supply and output portion of things of the amplifier simply cannot handle the demand that the output stage is wanting to get. When you do not have a subsonic filter...or one that is set improperly...you then start to make this thing that you've just microwaved move...

You are slamming the gates open/closed on the output transistors at 90+% duty cycle, which is absolutely asinine and they freak out.

Take a can of coke, pop the top open and bend it back and forth a few millimeters...within it's mechanical limitations that tab will never break. Now if you start to bend it past its mechanical limitations is when you start to get into trouble. This is where the subsonic filter comes in and making sure that you are not playing full power below port tuning frequency of a sub. If you already have something that's hot from running it hard on one of the Korean amps and you start yanking the soft parts past their mechanical limitations more and more heat builds up...

You get to the point where so much heat builds up that the spiders start smoldering...they won't catch on fire until you've clipped the signal to death, vaporized all of the flame retardant spray that the spiders are soaked in and then it smokes. (square wave form, dc voltage out of the amp because the power supply cannot handle what you are doing to it)

It's not the sub, there is absolutely nothing wrong with running those leads like they are. What's going on is an issue of the big cheap Korean amplifiers in and of themselves...and total ill-regard to what a microwave and conductive material does.

Hope this helps you understand...if you run a Crown A6000Gti you'll never have a problem...because it's an A/B amp....the other stuff that is cheap...don't run it below 1ohm or you are going to have nothing but problems because in order to get that big power cheaply and cut out on the parts that are going into the amplifier the switching frequency of the power supply must be ramped way up...in turn microwaving woofer parts.

:orly3::WTFBubble:

Yes, that is true, I think, that little which amp can work on on .5 ohm, daily. I think if you have a daily sub in daily(big) box, you have a very big box impedance rise, which mean that if you want more efficiency from amp ( :morepower1: without clipping, buy sub with dual 1 ohm wire and wire down to .5 ohm, because in real life you got 2ohm impedance or more, thats the point of this quote.

I don't know for woofer box without impedance rise. ^_^

So..after I explain why to not do something...you continue to say let's do it?

The last thing on your mind in a daily driving install should be impedance rise...in a musical application it simply does not matter!

SPL burping is another scenario.

Unless you want to invest heavily in recones...I'm telling you do NOT do it.

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Explains why they have the Cresendo 3K at .5 ohms?

Smooth.

-_-"

Jeeze, such a smart guy

It is called not knowing any better, and simply being a lemming and doing exactly what the manufacturer that really makes them says. It's simply not understanding how an amplifier works..in conjunction with a speaker.

When you start to drop an amp below 1ohm more heat is being built up because the power supply and output portion of things of the amplifier simply cannot handle the demand that the output stage is wanting to get. When you do not have a subsonic filter...or one that is set improperly...you then start to make this thing that you've just microwaved move...

You are slamming the gates open/closed on the output transistors at 90+% duty cycle, which is absolutely asinine and they freak out.

Take a can of coke, pop the top open and bend it back and forth a few millimeters...within it's mechanical limitations that tab will never break. Now if you start to bend it past its mechanical limitations is when you start to get into trouble. This is where the subsonic filter comes in and making sure that you are not playing full power below port tuning frequency of a sub. If you already have something that's hot from running it hard on one of the Korean amps and you start yanking the soft parts past their mechanical limitations more and more heat builds up...

You get to the point where so much heat builds up that the spiders start smoldering...they won't catch on fire until you've clipped the signal to death, vaporized all of the flame retardant spray that the spiders are soaked in and then it smokes. (square wave form, dc voltage out of the amp because the power supply cannot handle what you are doing to it)

It's not the sub, there is absolutely nothing wrong with running those leads like they are. What's going on is an issue of the big cheap Korean amplifiers in and of themselves...and total ill-regard to what a microwave and conductive material does.

Hope this helps you understand...if you run a Crown A6000Gti you'll never have a problem...because it's an A/B amp....the other stuff that is cheap...don't run it below 1ohm or you are going to have nothing but problems because in order to get that big power cheaply and cut out on the parts that are going into the amplifier the switching frequency of the power supply must be ramped way up...in turn microwaving woofer parts.

:orly3::WTFBubble:

Yes, that is true, I think, that little which amp can work on on .5 ohm, daily. I think if you have a daily sub in daily(big) box, you have a very big box impedance rise, which mean that if you want more efficiency from amp ( :morepower1: without clipping, buy sub with dual 1 ohm wire and wire down to .5 ohm, because in real life you got 2ohm impedance or more, thats the point of this quote.

I don't know for woofer box without impedance rise. ^_^

So..after I explain why to not do something...you continue to say let's do it?

The last thing on your mind in a daily driving install should be impedance rise...in a musical application it simply does not matter!

SPL burping is another scenario.

Unless you want to invest heavily in recones...I'm telling you do NOT do it.

It's sad, someone with such experience and knowledge in the field and yet people continue to ignore you. But hey, they pay the price in the end :attempt:

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Yeah..they pay the price in the end..if they would just slow down for 2 minutes and read they would never have an issue!

But they come at our head for a minute because we're at the end of the chain. The sub is the thing that makes the noise that they desire, so if it blows up then it is our warranty issue..

The only problem is warranty covers manufacturing defects, not ignorance or stupidity.

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Explains why they have the Cresendo 3K at .5 ohms?

Smooth.

-_-"

Jeeze, such a smart guy

It is called not knowing any better, and simply being a lemming and doing exactly what the manufacturer that really makes them says. It's simply not understanding how an amplifier works..in conjunction with a speaker.

When you start to drop an amp below 1ohm more heat is being built up because the power supply and output portion of things of the amplifier simply cannot handle the demand that the output stage is wanting to get. When you do not have a subsonic filter...or one that is set improperly...you then start to make this thing that you've just microwaved move...

You are slamming the gates open/closed on the output transistors at 90+% duty cycle, which is absolutely asinine and they freak out.

Take a can of coke, pop the top open and bend it back and forth a few millimeters...within it's mechanical limitations that tab will never break. Now if you start to bend it past its mechanical limitations is when you start to get into trouble. This is where the subsonic filter comes in and making sure that you are not playing full power below port tuning frequency of a sub. If you already have something that's hot from running it hard on one of the Korean amps and you start yanking the soft parts past their mechanical limitations more and more heat builds up...

You get to the point where so much heat builds up that the spiders start smoldering...they won't catch on fire until you've clipped the signal to death, vaporized all of the flame retardant spray that the spiders are soaked in and then it smokes. (square wave form, dc voltage out of the amp because the power supply cannot handle what you are doing to it)

It's not the sub, there is absolutely nothing wrong with running those leads like they are. What's going on is an issue of the big cheap Korean amplifiers in and of themselves...and total ill-regard to what a microwave and conductive material does.

Hope this helps you understand...if you run a Crown A6000Gti you'll never have a problem...because it's an A/B amp....the other stuff that is cheap...don't run it below 1ohm or you are going to have nothing but problems because in order to get that big power cheaply and cut out on the parts that are going into the amplifier the switching frequency of the power supply must be ramped way up...in turn microwaving woofer parts.

:orly3::WTFBubble:

Yes, that is true, I think, that little which amp can work on on .5 ohm, daily. I think if you have a daily sub in daily(big) box, you have a very big box impedance rise, which mean that if you want more efficiency from amp ( :morepower1: without clipping, buy sub with dual 1 ohm wire and wire down to .5 ohm, because in real life you got 2ohm impedance or more, thats the point of this quote.

I don't know for woofer box without impedance rise. ^_^

HAHAHAHAHA THAT IS THE MOST A$$ BACKWARDS THING I HAVE EVER HEARD!!! IF YOU PLOT THE IMPEDANCE IT'S OHMS VS FREQUENCY THE IMPEDANCE WILL RISE AT LIKE 60 Hz AND PLUMMET DOWN ELSEWHERE. New rule: if you don't have a degree in acoustics, don't speculate about things you have no chance of comprehending. Running an amp @ one ohm, even if its rated at one ohm, increases the TOTAL HARMONIC DISTORTION significantly, draws more current through the transistors which increases heat dissipation at a parabolic rate, and has MINIMAL RESULTING BENEFIT probably a SINGLE DECIBEL if ur lucky, 3 if you do it PERFECTLY. There's no reason to run an amp at half its lowest rated impedance, unless you want those transistors to all POP like pimples. I've seen it, they blow up. Ruin your THD and make your speakers non-linear. Nothing you said makes sense at all. Period.

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Lmfao..

Jebus

People take the internet to seriously.

Whole buncha ass clowns on here now a day just thinking they know.

Stang does, I'm not dissing, but watch me get banned

Fine by me

Either way, not knowing and knowing are two completely different things

My friend doesn't know shit and almost blew my old subs

I retuned it the correct way, viola, sounds amazing

I only need an amp that will run at .5 ohms only for car shows

Not like I'm dailying with the system at that ohm.

Though you assumed with your head that I was

But thanks for being a total helpful dick, LOL

Either way, my amp isn't stable past 2 and I plan on getting another Q dual 1 to run it at 1 ohm

hmm, sundown it is

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Lmfao..

Jebus

People take the internet to seriously.

Whole buncha ass clowns on here now a day just thinking they know.

Stang does, I'm not dissing, but watch me get banned

Fine by me

Either way, not knowing and knowing are two completely different things

My friend doesn't know shit and almost blew my old subs

I retuned it the correct way, viola, sounds amazing

I only need an amp that will run at .5 ohms only for car shows

Not like I'm dailying with the system at that ohm.

Though you assumed with your head that I was

But thanks for being a total helpful dick, LOL

Either way, my amp isn't stable past 2 and I plan on getting another Q dual 1 to run it at 1 ohm

hmm, sundown it is

I'm not being a smartass..

I'm trying to help you out and save you some money? I would not have spent the time to explain why you should not do something..if you should not do it.

Other people read these threads as well..they see you running it at .5ohm..and just like youtube video's you did it so i can to.

Things are not that simple...just because john force can drive a funny car doesn't mean you or I can too..and I've been around drag racing my entire life and I know that I can't hop in it and set records.

If you burn things up you simply can not say that I did not warn you...I do not want other users on this board to think that they can go do it. Because that is going to cause a bunch of recones...and I do not want that.

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Alright well to the people who say i should get a 15 instead of an 18, the box will only have to be 3" shorter, im sure i can make up that volume by increase the depth, it really wont be that hard... its a full size trunk, i can fit atleast 2 dead bodies :D

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i don't go around running my Q on .5 because i can even if the saz-3000D said it could do half ohm i don't have the electrical to back it up and i like my amp and plain on keeping it around for quite a few years.

so nick i know you have probably said this at one point or another but what do you think about how i have my rig set up. 15" Q on a saz-3000D @2 ohms in a 2.8^ft box tuned at 30hz or 32hz with aero. think its ok to leave it as is?

also what do you think about a loaded N2 (D2) for daily in the same box for spl events or fun, last question what are your thoughts on the saz-3000d as an amp and how it preforms at 4ohm, 2ohm, and 1omh loads.

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Lmfao..

Jebus

People take the internet to seriously.

Whole buncha ass clowns on here now a day just thinking they know.

Stang does, I'm not dissing, but watch me get banned

Fine by me

Either way, not knowing and knowing are two completely different things

My friend doesn't know shit and almost blew my old subs

I retuned it the correct way, viola, sounds amazing

I only need an amp that will run at .5 ohms only for car shows

Not like I'm dailying with the system at that ohm.

Though you assumed with your head that I was

But thanks for being a total helpful dick, LOL

Either way, my amp isn't stable past 2 and I plan on getting another Q dual 1 to run it at 1 ohm

hmm, sundown it is

I apologize for trying to keep the internet free of misinformation... for the record I've hand-built more amplifiers than sundown has sold to date. If you don't wanna take advice from the Fi moderators you shouldn't be on this forum.

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i don't go around running my Q on .5 because i can even if the saz-3000D said it could do half ohm i don't have the electrical to back it up and i like my amp and plain on keeping it around for quite a few years.

so nick i know you have probably said this at one point or another but what do you think about how i have my rig set up. 15" Q on a saz-3000D @2 ohms in a 2.8^ft box tuned at 30hz or 32hz with aero. think its ok to leave it as is?

also what do you think about a loaded N2 (D2) for daily in the same box for spl events or fun, last question what are your thoughts on the saz-3000d as an amp and how it preforms at 4ohm, 2ohm, and 1omh loads.

Begin rant:

:stands on soap box:

You don't want to get me started on any amps from Korea/China :) I will rant about them for days. Stephen Mantz and I feel the same way about them...it's kind of scary of how similar our views are.

They're cheap..and they work ok to a point. But there is so much stupidity behind how they work and what they are doing it is annoying that an "engineer" would come up with what they do/did. The build houses in China/Korea are all about cutting cost and parts because they make a billion of the same things a year. If you can save a dollar on every board, that is a billion dollars which adds up..I can understand that. But me, being me and how Scott and I stay true to what we do and how we do things...I, myself will never be a person to buy something and resell it and have no hand in it at all other then the UPS label, sorry. It is not my style. I am a control freak and I refuse to associate myself with anything that I do not truly do myself here, in the states. I'd feel like an ass buying amplifiers and marking them up 150% to turn profit on something where I had zero effort in..and truly do not know how every single component works and its function as a whole. Only for somebody else to "borrow" what "I" came up with and put it in a different case and call it their own and undercut me and sell them for 100% per unit margin. When I get involved in something, I know it inside..out..and backwards through the entire process. You have far less 'copies' or 'knockoffs' when you actually build everything yourself and machine parts in house and have the machinery to do what you need to do.

/rant.

2.8 cubes is a wee small for the N2's. It would be ok for a burp if that is what you are trying to do...for musical applications it is going to be a tad peaky and anemic on the bottom end.

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so if it was you what would your amp of choice be and what would would be the smallest box you would put the N2 in for daily.

also would FI ever make an amp?

sorry to keep wasting your time just like your point of view on things.

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so if it was you what would your amp of choice be and what would would be the smallest box you would put the N2 in for daily.

also would FI ever make an amp?

sorry to keep wasting your time just like your point of view on things.

My personal amp of choice is between the old zapco 9.0's, and the Crown amplifiers from JBL the bpx2200.1 was a FANTASTIC amp.

I vow to my grave to never have anything to do with an amplifier until I do it myself..in house.

If it happens..cool..if not, that's cool too. I see no point in jumping in a pool that 30 other people have already peed in and are swimming in. That's just stupid.

3 cubes is the bare minimum I would use one in myself..the smaller you make it the more the bottom end is going to be anemic.

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Oh my, it seems we arent even talking about my setup anymore ^^ haha

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thanks for your time nick.

Not a problem sir

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I agree with stang as well... the most useful part of most mass-produced amps are the heatsinks. Rip out the guts and you have a nice platform to start mounting some real fets (the kind you can only buy in ridiculous bulk for about 15 grand), an industrial power supply, mock up a basic signal processor and balance current demands and voila you got an amp! It's amazing how much better a well-built amplifier performs with proper components. I prefer smaller analog-style amps but some of my students graduate up to some pretty beefy digital circuitry. had one kid from England who took his Lanzar/ legacy p.o.s. stripped it and designed his own got around 2300 watt output, after a small headache cramming in so many fets. he was so happy he gave it to me as a gift when he graduated and moved back to England. now its in my fiance's jeep liberty mounted under the backseat; been pounding away for about 5 years now without really getting warm even (@4 ohms). I'm lucky to have lots of circuit components at my disposal tho

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I agree with stang as well... the most useful part of most mass-produced amps are the heatsinks. Rip out the guts and you have a nice platform to start mounting some real fets (the kind you can only buy in ridiculous bulk for about 15 grand), an industrial power supply, mock up a basic signal processor and balance current demands and voila you got an amp! It's amazing how much better a well-built amplifier performs with proper components. I prefer smaller analog-style amps but some of my students graduate up to some pretty beefy digital circuitry. had one kid from England who took his Lanzar/ legacy p.o.s. stripped it and designed his own got around 2300 watt output, after a small headache cramming in so many fets. he was so happy he gave it to me as a gift when he graduated and moved back to England. now its in my fiance's jeep liberty mounted under the backseat; been pounding away for about 5 years now without really getting warm even (@4 ohms). I'm lucky to have lots of circuit components at my disposal tho

might be fun to rebuild my saz-3k some day.

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I agree with stang as well... the most useful part of most mass-produced amps are the heatsinks. Rip out the guts and you have a nice platform to start mounting some real fets (the kind you can only buy in ridiculous bulk for about 15 grand), an industrial power supply, mock up a basic signal processor and balance current demands and voila you got an amp! It's amazing how much better a well-built amplifier performs with proper components. I prefer smaller analog-style amps but some of my students graduate up to some pretty beefy digital circuitry. had one kid from England who took his Lanzar/ legacy p.o.s. stripped it and designed his own got around 2300 watt output, after a small headache cramming in so many fets. he was so happy he gave it to me as a gift when he graduated and moved back to England. now its in my fiance's jeep liberty mounted under the backseat; been pounding away for about 5 years now without really getting warm even (@4 ohms). I'm lucky to have lots of circuit components at my disposal tho

might be fun to rebuild my saz-3k some day.

Come on up to Rensselaer Polytechnic Institute in Albany during a school year and ill be happy to walk you through it... just sign up for some simple class, they love eager students in the machine shop :)

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I agree with stang as well... the most useful part of most mass-produced amps are the heatsinks. Rip out the guts and you have a nice platform to start mounting some real fets (the kind you can only buy in ridiculous bulk for about 15 grand), an industrial power supply, mock up a basic signal processor and balance current demands and voila you got an amp! It's amazing how much better a well-built amplifier performs with proper components. I prefer smaller analog-style amps but some of my students graduate up to some pretty beefy digital circuitry. had one kid from England who took his Lanzar/ legacy p.o.s. stripped it and designed his own got around 2300 watt output, after a small headache cramming in so many fets. he was so happy he gave it to me as a gift when he graduated and moved back to England. now its in my fiance's jeep liberty mounted under the backseat; been pounding away for about 5 years now without really getting warm even (@4 ohms). I'm lucky to have lots of circuit components at my disposal tho

Ahh..4ohm power. I don't like 2ohm power..but I can deal with it and have dealt with it.

I don't mind a switching power supply...IF it is done properly..and well, you know as well as I do..switching shit at 120kHz is going to cause nothing but problems, but DAMN is it cheap.

Have we crossed paths before?

:)

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Alright, now i dont want to seem like i want everyone else to do my work for me, Iv just never built a box before... iv been trying to read up on how to measure the inside volume and the port ect. But I really dont understand it :S.. Now refering back to the suggested cut out sheet by Fi, i can keep all the dimensions the same except for the 22" height, the max i can make it is about 19". With that in mind how would i be able to change the box so i can keep it at the 7.00 cubic feet.. Sorry again, i dont want to seem lazy i just really cant wrap my head around it right now.

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