Normal Practice To Use 6 1/2" Sub With 8" Speaker?


I have a PMC TLE1 subwoofer with dual 6 1/2" drivers and speakers with 8" drivers. I am thinking whether it is a norm to combine subwoofers with speakers that have bigger drivers. The PMC subwoofer with smaller drivers goes down flat to 22Hz while the speaker with bigger drivers goes down to 40Hz+/-3dB. I am just curious since my impression is it is more appropriate to use subwoofers with a driver size that is at least similar or larger than the speaker's driver apart from looking at the specifications.

In my case I reckon it is technically acceptable to hook up the sub to the speakers since it does go down lower than the speakers? I just feel a little awkward using a sub that has smaller drivers compared to the main speakers although the results can be good(I think).

Any advice would be appreciated.
ryder
Your sub is a Transmission Line design. The size of the drivers being 6 1/2 inches is less important than the design of the box they mount into. The box itself is tuned to play that low in frequency by the length of the line built within them using those specific drivers. Two six inch drivers will move a consciderable amount of air , much like a single 12 inch would. Focal use to sell 4 inch subs that played ridiculously low and punchy. The size of the driver in subs depends on the quality and design ( sealed, ported, TLE) of the sub enclosure. Large drivers do not dictate the quality of bass you hear in either 2 channel or home theatre. Cheers
The main thing I believe is,does the sub woofer have the sound pressure to match the speakers? What I'm trying to say is,if your playing your speakers at the loudest level you like,will the sub produce the low frequencies you like at the same level?And do so without distortion or stress?If it does I don't see why not.
Has,
Please 'do the math'.
Double the diameter of a circle and the area goes up 4X.

This means that 2x6" drivers have half the area of a single 12.
Large drivers do not dictate the quality of bass you hear in either 2 channel or home theatre

Perhaps not but they sure determine the quantity of good quality bass. Only large drivers (several of them) will get you up into the 110 db SPL at 20 Hz with low distortion.
quality VS quantity. The eternal struggle.

But of course, as the Russians (military) say, 'Quantity has a quality all its own'.