I have asked this question before and been told that it is ill-advised but I suspect the answers are led by the lack of facilities to calculate.
Logically, two 6.5" woofers in a 20l cabinet will perform better than one. By the same logic two 6.5" subwoofers in that same cabinet will perform better than one. Subsequently, one subwoofer and one woofer will offer better bass performance than two woofers. Perhaps lower the bottom end by 10hz?
I ask the question because many floor-standing speakers appear to be a waste of volume.
The simplest solution would be to wire the drivers in parallel. However, a rumble level high-pass filter on the woofer could be used, but this brings the passive radiator effect into the equation.
What factors govern the frequency response of a driver? e.g. If I feed 25Hz into the sub driver it oscillates wildly, The same signal into the woofer is largely ignored.
Thoughts.
Logically, two 6.5" woofers in a 20l cabinet will perform better than one. By the same logic two 6.5" subwoofers in that same cabinet will perform better than one. Subsequently, one subwoofer and one woofer will offer better bass performance than two woofers. Perhaps lower the bottom end by 10hz?
I ask the question because many floor-standing speakers appear to be a waste of volume.
The simplest solution would be to wire the drivers in parallel. However, a rumble level high-pass filter on the woofer could be used, but this brings the passive radiator effect into the equation.
What factors govern the frequency response of a driver? e.g. If I feed 25Hz into the sub driver it oscillates wildly, The same signal into the woofer is largely ignored.
Thoughts.
Two drivers of the same type can share the same enclosure without any issues but need twice of the volume. Two different drivers can't perform equally good because each got it's own behaviour (TSP) and need a fitting alignment. I have never seen a subwoofer with the same specs. You will always have a better performance by using two separate enclosures. You may put th in the same but don't expect too much. It will work...but nothing more. The outcome can only be checked by an experiment - build both, measure, have your answer.
This is the part that I'm not convinced of. Let me try to explain why . . .
Back in the day I owned Fane 'disco' speakers: (2 x 12" drivers = 2 Piezo tweeters). One of the Fane drivers retired so had to be replaced. The cheap driver I replaced it with has a lower Fs than the original driver. The result was vastly improved bass response - so much so, I replaced one of the drivers in the other cabinet.
A good ROT is to average the driver specs to design with: http://community.fortunecity.ws/rivendell/xentar/1179/theory/dddllqd/dddllqd.html
Why do you bother asking people question, when you already made up your mind.
I am sure you made no measurements. Maybe your improvement with mismatched driver would not look so good on fr response or phase.
On the contrary, why get involved if you don't have the answer? The bulk of your comments can be summarised as "I don't know the answer without a calculator."
My first speakers were a pair of Leak Sandwiches, 200s I think. These were manufactured in the seventies. T/S Parameters were not written into the Gospel of Loudspeaker design until the mid-eighties. How Harold Leak designed such wonderful speakers with crucial information remains a mystery!
I am reliably informed that loudspeaker drivers are batch analysed and the published T/S parameter are an average. The parameters for individual drivers may vary by as much as 30%. Most drivers are tested as new, T/S parameters change over time.
As I've no intention of producing a pair of NS10 clones I really don't care how something looks on a simulator. I hear with my ears. My ideal speaker system sounds sharp at the top and warm at the bottom.
