Page 15 of 21

Re: Introducing SPL Chart

Posted: Thu Feb 23, 2012 2:29 pm
by Bill Fitzmaurice
It's not the driver, it's the cab. :horse:

Re: Introducing SPL Chart

Posted: Thu Feb 23, 2012 3:55 pm
by Gregory East
That's not really true is it?

In the case of 3015lf v lab15 it works out a wash, but that's not the same as saying the driver doesn't matter as far as sensitivity goes.

Re: Introducing SPL Chart

Posted: Thu Feb 23, 2012 5:35 pm
by GrooveFrequencies
So your saying that the response for both drivers is the same, as well as output? Sorry for all the questions, its just alot of time and money to invest. And i want to make sure i build something i'm happy with. I notice that with all your designs, sensitivity varies with different drivers...obviously some are superior to others as far as output is concerned....or am i a completely wrong???

Re: Introducing SPL Chart

Posted: Thu Feb 23, 2012 6:04 pm
by GrooveFrequencies
Bill Fitzmaurice wrote:
DaveK wrote:Bass players, check this out! Jack210 == Omni 15
-1. Jack 210 is 4 ohms, O15 is 8. Jack 210 has 294cc displacement, O15 has 846cc. SPL charts alone do not tell the whole story. And there's still no such thing as a free lunch.
The reason i asked was the 3015lf has a vd of 846cc and 450w power handling, compared to the lab 15's 968cc and 600w power handling. So wouldn't the Lab have more output that the 3015lf in the new t48 design?!? i get that the cab has alot to do with it but does this make no difference?

Re: Introducing SPL Chart

Posted: Thu Feb 23, 2012 6:10 pm
by Bill Fitzmaurice
Gregory East wrote:That's not really true is it?

In the case of 3015lf v lab15 it works out a wash, but that's not the same as saying the driver doesn't matter as far as sensitivity goes.
True, if the driver doesn't have compatible specs it won't give the sensitivity and response that one with compatible specs will.
The reason i asked was the 3015lf has a vd of 846cc and 450w power handling, compared to the lab 15's 968cc and 600w power handling. So wouldn't the Lab have more output that the 3015lf in the new t48 design?
No, because the Lab doesn't have specs that work as well as the 3015LF. It wouldn't be in the plans at all if it were not for the rise in neo driver prices and their sometimes tenuous availability. So while it has a higher Pe and xmax it doesn't work any better, just about the same.

Re: Introducing SPL Chart

Posted: Thu Feb 23, 2012 6:19 pm
by GrooveFrequencies
Thanks bill! No free lunch for me haha. Thanks for setting me straight :D

Re: Introducing SPL Chart

Posted: Thu Mar 08, 2012 1:34 pm
by Saginaw Sound
Reading all this leads me to believe that there was a specific driver in mind during the design process. As I have the CD I see each of the plans say pretty much the same thing.

The least expensive recommended driver is the DRIVER A. To check pro-sound drivers for suitability the acceptable Fs is between xx and xx Hz, Qts from .xx to .xx, xmax no less than x mm. Upgrade Eminence drivers include the DRIVER B, DRIVER C and DRIVER D. Ultra light options include the DRIVER E and DRIVER F. You also may load it with a twelve with similar specs, such as the DRIVER G and DRIVER H, DRIVER I and DRIVER J.

I have no idea what software program is utilized in making the plans for the cabinets and I have no idea what comes first... The driver and it's specs, or the plan that dictates what the specs of the driver are to be.

In the first scenario (if the driver and it's specs were inserted into a computer and the cabinets were designed), I would like to know what drivers were these designed modeled after. If this is the case, where can we get the list that will make our new cabinets sing as they were designed to?

In the second scenario (if the plan is drawn up and a general driver spec is produced from the plan) then I can see where it would have much room for personal preference on driver selection including variables such as money and weight. If this is the case, then there is much room for experimentation of drivers used provided it's within the recommended specs.

Re: Introducing SPL Chart

Posted: Thu Mar 08, 2012 3:02 pm
by Gregory East
There are premium expensive drivers for t48 but they don't get much discussion because 1 they're bloody dear 2 they give hardly any extra spl.

Drivers suitable for horn cabs are rare.

I gather from Leland's post on your thread that the 3015lf has dropped back in price enough to make lab15's sit on the shelf.

Re: Introducing SPL Chart

Posted: Fri Mar 09, 2012 12:59 am
by SeisTres
I think Bill started with the drivers that gave the most performance for the money and modeled his cabs to accommodate them. Revision being made as they were phased out and new drivers introduced.

So basically they're made to work best with the 2510,2512,2515,3012lf,3015lf. I remember reading long ago the titan 48 was introduced even before the 3015lf was available, so i guess the idea varies somewhat. Anything other than that and basically we're deviating from the "optimal" drivers.

Re: Introducing SPL Chart

Posted: Fri Mar 09, 2012 9:02 am
by Saginaw Sound
That's all I want to do. Build the best cabinet with the best matched driver.

I'm finding the LAB 15 for 190 out the door. 3015lf is 198 out the door.

15 lbs difference would be worth an extra $8.

Re: Introducing SPL Chart

Posted: Fri Mar 09, 2012 10:22 am
by Bill Fitzmaurice
Saginaw Sound wrote:That's all I want to do. Build the best cabinet with the best matched driver.
Have you read the plans?

T39 and T48 comparison spls

Posted: Mon Apr 02, 2012 1:32 pm
by Rich4349
Just comparing some Titan variations.

( red) SIX 36" wide T48s vplated

( royal ) SIX 24" wide T48s vplated

(kelly green) FOUR 30" wide T39s vplated

( maroon ) TWO 36" wide T48s vplated

(navy blue) TWO 30" wide T39s vplated

(forest grn) FOUR 27" wide T60

(turqoise ) TWO 27" wide T60s

( purple) ONE 27" wide T60s



Also shown are associated high pass points for 2 or 4 (OR MORE) Titans. Performance below these lines FOR TITANS should be disregarded. Here the T60 reigns supreme.

And, yes, I can see that this chart is close to a cluster feck, visually. :ugeek:


Re: Introducing SPL Chart

Posted: Sun Aug 26, 2012 11:15 pm
by Dan30
Anyone have a chart of a QSC K12? I'd like to compare it to my Yammie.

Re: Introducing SPL Chart

Posted: Mon Aug 27, 2012 7:44 am
by Bill Fitzmaurice
Dan30 wrote:Anyone have a chart of a QSC K12? I'd like to compare it to my Yammie.
Even QSC doesn't have one. :roll:

Re: Introducing SPL Chart

Posted: Tue Aug 28, 2012 11:57 am
by BrentEvans
Bill Fitzmaurice wrote:
Dan30 wrote:Anyone have a chart of a QSC K12? I'd like to compare it to my Yammie.
Even QSC doesn't have one. :roll:
Might that be because, being an active speaker, they are doing some DSP correction inside the box, making any raw response chart irrelevant, and any corrected response chart nearly useless?