Help choosing a midrange setup ( W15 or W18 Nextel drivers ) please.

[Branwell]

Hello,

I am hoping for some opinions. Some input.

If you where to do a 3 way and where given a choice between two midranges setups, which would you chose and why ?.

The tweeter would be a Seas Millennium, and the bass, a pair of non sub bass drivers per side allowing a crossover point as high as 500hz if needed.

The crossover is a DEQX, so you have no crossover concerns.

The midrange choices are :

1. A single Seas W18 Nextel per side. ( WWMT )
2. A pair of Seas W15 Nextels per side ( WWMTM )

So…what would you do and why ?.

Thanks,

Branwell

[Paul H]

First let me say I haven't seen or heard these drivers, just looked at some spec sheets... but I'd use the W18.

One major reason to use the W15's that I can see is to cross over to the tweeter higher. However, using two W15's the centre-centre distance is going to be at least 9", which according to rules of thumb I've picked up on this forum and checked myself during testing would suggest a max crossover point around 1500 Hz. A higher crossover at that spacing will tend to reveal the two drivers as separate sound sources, rather than a single combined. The W18 can certainly be crossed this high - I'd actually suggest around 1500-1600.

Breakup modes on the W15 is only slightly higher than the W18 (~ 5,000 vs 4,000).

The W15 has a curious bump in the impedance around 800-900 Hz which may suggest some problems/distortion??

One W18 is cheaper than two W15's.

If you were going passive there might be some benefit in the higher efficiency of two paralelled mids, but you're using active crossovers, so no advantage there.

Two W15's in mtm would have less vertical dispersion; whether that's better or worse for you depends on your intended use.

That's my 2 cents ..

Paul