Mid-Size solution - FBT Verve 8ma

[Jed]

Thanks for the link . As far as 2 8's equaling a 16 youre correct they dont exactly equall a 16 but the surface area of the cones are close and 2 8's will absolutly have more low mids /bass than 1 8 .Maybe as much as 1 12 .

You may want to revisit the math involved on this. A single 8" driver has about 1/4 the surface area of a single 16" driver. Assuming flat drivers (which real drivers are not) a single 8" driver would have about 50.24 sq inches of cone area, while a single 16" driver would have about 201 sq inches of cone area.

In order to determine the actual surface area of a real world driver you would also need to know several details about the driver - true diameter (less the surround), angle of cone, dimensions of the center cap, etc.

 

[Jay Mitchell]

You may want to revisit the math involved on this.

Good idea. The parameter of importance is effective piston area. A good rule of thumb is that the piston radius in centimeters is approximately equal to the nominal diameter in inches. Therefore an 8" speaker has an effective piston radius of approximately 8cm, or 3.15".

Using the above formula, the approximate effective piston areas for three common speaker sizes are:

8" - 31.16 in^2

12" - 70.12 in^2

15" - 109.56 in^2

From the standpoint of loudspeaker design, there is no point in pursuing the concept of effective piston area any further than the above approximation. There are other parameters that affect the output capacity of the speaker. Everything else being equal - i.e., identical motor assemblies - a larger cone transducer will be more efficient at low frequencies, but everything else is never equal.

 

[Groovey Records]

Everything else being equal - i.e., identical motor assemblies - a larger cone transducer will be more efficient at low frequencies, but everything else is never equal.

Well said Everything Else never is ! :lol:

Great explanation on the theory Thanks Jay

 

[Scott Peterson]

Hey Scott just wanted to get more of your imput on the fulness of sound you are getting from the new Verve compared to your QSC as you have time to use it in larger settings and with live drummers on different stages. This may be an unfair comparisom 'cus the QSC is huge and has a 12" speaker and the Verve 8ma is 8" speaker, but I was wondering if you could describe what you are missing in the tone comparison. And I am wondering if the FBT 8ma would keep up as a single monitor source with a heavy drummer or would the QSC always be the choice for a larger stage? I believe that I have read before that the QSC feels the closest to a "real amp" or has that "in the room" feel. Are you getting most of that with the FBT? Real interested in your continued imput as you use the FBT in multiple applications.

An 8" no matter how well designed or built cannot push the volume of air a well designed and built 12" speaker can. The QSC brings a different response curve, though still pleasing and musical. It's simply a well done speaker. The FBT is totally a different animal though, 8" does not equal 12" for sheer power on the low end. The 8ma has a very tight low end, not muddy and does not break up. It does NOT have the low end extension nor the somewhat ambiguous yet popular 'thump'.

For bigger, louder, jiggle your nuts low end, go with the QSC. The 8ma will work on the loudest stage as a personal monitor, but won't make your nuts jiggle unless you are sitting on top of it (not recommended : :shock: )

 

[quonsar]

Jay, do you have a formula that translates effective piston area to absolute nut jiggle? :lol:

 

[Jed]

From the standpoint of loudspeaker design, there is no point in pursuing the concept of effective piston area any further than the above approximation. There are other parameters that affect the output capacity of the speaker. Everything else being equal - i.e., identical motor assemblies - a larger cone transducer will be more efficient at low frequencies, but everything else is never equal.

Jay thanks for the clarification / correction. I know enough math to realize that the original logic was way off but I know almost nothing about actual speaker function. I really appreciate your expertise, . . I only wish I actually understood things on a much deeper level. The shear volume of mis-information and mis-conceptions about such things must drive you nuts.

cheers,

Jed