Blew my 12".....AGAIN!!!!!

[Arjank]

I just read the title, "Blew my 12".....AGAIN!!!!!" and not the OP or any of the follow up posts, but I congratulate you not only on your physical endowment, but your flexibility as well.

With 12" you ain't that flexible though

 

[Coolhandjjl]

And I've seen 5" drivers that couldn't handle an AM radio.

There are crappy drivers made everyday. But, all things being equal, a larger driver can always go lower with more volume. It's based entirely on the ability to move air.

Get a 10" speaker with great excursion, and a 15" with e same excursion, and the 15" will go lower every single time.

All things are never equal, so those analogies aren't very useful.

I suggest some review of the basics first.
Thiele/Small - Wikipedia, the free encyclopedia
The Thiele/Small Parameters have been around since the '70s, but are the industry standard for describing driver characteristics and behavior.

Speaker size alone is not very useful criteria at all in determining how much air can be displaced.
In addition to the T/S Parameters, there is tuning frequency, multiple driver coupling, box design, etc. There are engineered cabs using 8" drivers that more more air than an 18".

....Forcing a smaller driver to inefficiently drive down where a larger speaker can do it easily is a massive waste of time, energy and money.

A properly engineered cab does not force anything. Again, just because a driver has a larger diameter than another does not mean it can go lower or louder.

A wall of 5" drivers, is nothing but a different way to move the same amount of air, as far fewer 15" or 18" drivers.
...

Again, mis-information. Even if the surface area and excursion of the 15 was equal to the sum of surface area of an array of smaller ones, IE moving the same amount of air, the array of smaller ones wins every time. Why? Because it's an array! And arrays couple the sound waves of multiple drivers together to add more dBs than merely the sum of individual displacement.

5" drivers have a better transient response. That's why it's clear. It has the low end because of the number of drivers.

Compared to what? I bet you are one of those that believe that 10's are "faster" than 15's.

It was pointed out earlier that there are no single 10" cabinets. It's because that cabinet would be utterly useless.

There are many high quality and well engineered 1x10 bass cabs available. Even 1x8 ones. Stop spreading mis-information.

....
I'm not going to post a resume here, but I have worked with some of the finest loudspeakers in the world - Bowers and Wilkins - and I know what I'm talking about....

Hi-Fi and backline/pro audio are two entirely different animals. Their goals are very different.

Yeah. I passed high school math.

They are almost identical in surface area. But nice try.

Cone surface area is a much more useful measurement than cone diameter. Surface area more accurately describes the volume of air moved and the frequency response of the driver. Some drivers are straight sides, some are curved wall, some have large dustups, some have small dustcaps, some have flatter dust caps, some are spherical. All these variables translates into the volume of air moved and at what frequencies.

 

[Honch]

... I've been using it as the low end of a biAmp setup with only frequencies below 100Khz going to it...

little wonder, you bat...the rest of us don't consider 100 Khz "low end" or even hear it. Let alone any speaker that can handle it at all...But if you do, kudos...

Sorry, I couldn't help myself...although I know there's a K too much in there...only bats can hear up there...

 

[CL400Peavey]

Guys.... We are getting majorly off topic.

Do any of you have recommendations for the 6th, 7th, and 8th drivers this guy should buy?

 

[Bill Whitehurst]

OP
you are working yourself way too hard.
I too have a BX 1500.
I just built a fEARful 15/6/1 and run it
bridged.
900 watts, full range.
Clean.
Clear.
Deep.
Only one 55 pound cab to move.

OK, not real cheap, but probably cheaper than
the 5 speakers you have already killed.

 

[Arjank]

Guys.... We are getting majorly off topic.

Do any of you have recommendations for the 6th, 7th, and 8th drivers this guy should buy?

Yes, as far as potent 12" drivers go [Invalid or Expired Link Removed]

 

[Coolhandjjl]

If a 12 isn't gonna do the job ( and it always did....till it blew that is) Then yes, I suppose I would swap the 12 for a 15. But then I get into the " what's a portable 15" cab that will act as a good low range cab in a BiAmp rig?

ooh boy....

A high quality and appropriately spec'd 12" can easily beat out a mediocre 15". I used to have an Ampeg B100R Rocket Bass 100 watt combo amp. Nice for coffee shops, but that 15" driver would fart out when the lows were pushed, and pretty much come to the verge of destroying itself when playing with a loud drummer. OTHO, a fEARful 12/6 or fEARful 12sub can easily handle a 500 watt head, hit an SPL of 122dBs with that power, and be only approx -3dB at 47Hz. That's much higher output and better low end response than your Avatar.

 

[kosmicwizard]

I think you meant HIGH pass filter. And the frequency at which it is set would depend largely on the cabinet, driver, acoustic slope, etc... best done with modeling software.

Whether or not i used the right words doesn't really matter. At least he got my point and i was genuinely trying to help, unlike a lot of other sarcastic responses in thus thread. Modelling software or not he is sending too much through if he is sending everything below 100kHz.

 

[BurningSkies]

Also, yes there are a few cabs with single 10's that can go low. Speaker size doesn't have to do with what it can produce in terms of low...but it has more to how efficiently it can do it. Its the reason that PJB can use those little drivers but uses a whole bunch of them. Of course, the other factor that one may have to take into account is dispersion in the mids.

How much volume per watt is based upon displacement which is based upon excursion and driver area. The OP is picking drivers that don't move far enough and/or aren't moving the amount of air he requires. In this case you pick a driver that moves more air by way of longer excursion or bigger cone area.

I would also agree that the OP should consider using an HPF such as the HPF-3 by FDeck to trim the signal below 30~35hz. It won't noticeably alter the audible tone, but will protect drivers from killing them dead due to over excursion.

 

[Coolhandjjl]

May I suggest that you just don't have enough rig for the gig?

The math is pretty simple actually... Knowing the SPL sensitivity at 1 watt/1meter at the lowest frequency you intend to reproduce, then extrapolate to the safe power handling of the speaker (using the RMS or continuous rating, not the program or peak rating) if the resulting number is less than your needed SPL at whatever distance you need it at then you do not have enough rig to accomplish what you hope.

These are exactly the calculations used when determining how much PA is needed in a touring rig to get the job done acceptably.

I suspect that you are WAY off in the ability of any 112 to meet your needs.

Great post.

There are few 112 cabs that can do rock with a loud drummer at the levels needed in a bar. This is the niche the boutique small companies and DIY engineers have filled. Greenboy Designs (fEARful/FEARLESS), AudioKinesis, Barefaced, Baer, MAS, Bill Fitzmaurice, probably forgot a few. They cost more, but are worth it.

 

[Arjank]

Hi-Fi and backline/pro audio are two entirely different animals.

Well, you can make exceptional sounding Hifi loudspeakers with pro audio drivers but not the other way around.

 

[dheafey]

Whether or not i used the right words doesn't really matter. At least he got my point and i was genuinely trying to help, unlike a lot of other sarcastic responses in thus thread. Modelling software or not he is sending too much through if he is sending everything below 100kHz.

It's not a case of "right words". HPF vs. LPF are circuits used to do specific things. If you get them wrong, it'll either sound like crap and/or you'll blow your speaker, again. My bad if you deem my response sarcastic; it wasn't meant to be.

 

[DwaynieAD]

this has gotta be a troll

 

[Coolhandjjl]

But this "all a speaker size tells is its size" nonsense needs to stop.

Not nonsense, fact.

Where's Bill Fitzmaurice when you need him!!

 

[Jim Carr]

Thiele/Small - Wikipedia, the free encyclopedia

All things are never equal, so those analogies aren't very useful.

Speaker size is only one of many criteria that determines how much air can be displaced.
In addition to the T/S Parameters, there is tuning frequency, multiple drivers coupling, box design, etc. There are engineered cabs using 8" drivers that more more air than an 18".

A properly engineered cab does not force anything. Again, just because a driver has a larger diameter than another does not mean it can go lower or louder.

...Even if the surface area and excursion of the 15 was equal to the sum of surface area of an array of smaller ones, IE moving the same amount of air, the array of smaller ones wins every time. Why? Because it's an array! And arrays couple the sound waves of multiple drivers together to add more dBs than merely the sum of individual displacement.

...I bet you are one of those that believe that 10's are "faster" than 15's.

There are many high quality and well engineered 1x10 bass cabs available. Even 8" ones. Stop spreading mis-information.
Hi-Fi and backline/pro audio are two entirely different animals. Their goal are very different.

Surface area is a much more useful measurement than cone diameter. Surface area more accurately describes the volume of air moved and the frequency response of the driver. Some drivers are straight sides, some are curved wall, some have large dustcaps, some have small dustcaps, some have flatter dust caps, some are spherical. All these variables translates into the volume of air moved and at what frequencies.

Now there you go again, citing facts! What a nerd.

 

[agedhorse]

If you guys were to do the math, I don't think ANY of the recommendations for a single 12" driver will get the necessary SPL at enough LF extension with the 300 watts available. I also suspect that the amp is being driven hard into clipping, so a thermal rating of ~500 watts would be necessary to survive. That takes away the higher sensitivity driver options too.

 

[Arjank]

That's why I recommended the BMS driver which can handle 800watts and has dito mechanical abilities, problem is that you need more amp power, 300watts ain't enough.....You can't have small cab, low-end extension and high sensitivity...

 

[CL400Peavey]

If you guys were to do the math, I don't think ANY of the recommendations for a single 12" driver will get the necessary SPL at enough LF extension with the 300 watts available. I also suspect that the amp is being driven hard into clipping, so a thermal rating of ~500 watts would be necessary to survive. That takes away the higher sensitivity driver options too.

You cool it with your logic in this thread... The OP is going to keep destroying 12" drivers until some magic driver comes to him.

 

[InhumanResource]

You probably just got some bad drivers.

I say you get another and go again.

5 bad drivers in a row? Somehow I doubt it. He is asking too much of the 112 with this setup.

 

[BurningSkies]

5 bad drivers in a row? Somehow I doubt it. He is asking too much of the 112 with this setup.

Anyone can see that with 24 likes on my comment that all of TB's membership endorses the fact that he's just gotten 5 bad drivers and there's no way that it's user error.