Question - Mismatched Speakers within same cab

[bassman08]

I currently have an empty 4x10 that I'm considering loading with the following:

2 10's rated at 200W RMS with a 2" voice-coil and 50 oz magnets, sensitivity 99db, stamped frame, xmax .25 - frequency range 65 - 7000 hz

2 10's rated at 250W RMS with a 3" voice-coil and 50 oz magnets, sensitivity 96 db, cast frame, xmax .25 - frequency range 50 - 4500 hz

I have not decided if I'm going to add a tweeter driver or not to the cabinet yet (it currently doesn't have one).

I know that the specs for the 250W speakers suggest they are better made (with the exception of the sensitivity). The reason I am considering using two different types of speakers is to cover a broader spectrum in the frequency range. I like my cabinets to have good note articulation and I know the treble frequencies add to how crisp the sound of the notes will be.

Is all this a bad idea and should I just pick one type of speaker and load with all 4 the same? Or maybe, should I just change one of the drivers and leave the other three the same?

If I make them all the same, I'm leaning toward the 250W speakers, but any input on this would be greatly appreciated.

 

[ESP-LTD]

I would be surprised if those specs on the cheaper ones are accurate; if it has a .25" Xmax I bet it doesn't do 7k AND have 99db sensitivity. On the better speaker, the specs make more sense but I'd want to see the rest of the specs (like Qts, XMech and such). A 50 oz magnet isn't much considering the length of the voice coil to go .25" I think I'd use something that said Eminence, where I knew what I was really trading off.

I'd stick to one type unless you want to internally partition the cab into seperate parts.

 

[billfitzmaurice]

The mismatched drivers are the least of your concerns. If the cabinet tuning isn't matched to the drivers T/S parameters it won't function optimally. The specs that you've quoted affect response far less than do fs, Vas, and Qts.

 

[Petebass]

The mismatched drivers are the least of your concerns. If the cabinet tuning isn't matched to the drivers T/S parameters it won't function optimally.

Agreed. If you must used mismatched speakers, always use the "two cabs within one cab" method. By isolating each type of speaker into it's own chamber, you can tune each part of the cab seperately. In other words, if one lot of speakers needs to be tuned to say 50Hz, and the other lot of speakers to 40Hz, you can do this without any problems. If all 4 speakers are sharing one chamber, it's impossible to tune the cab correctly.