PA speaker cabs - 2way vs 3way

[Barisaxman]

My experience is that most three way cabinets (MI Grade, we're not talking concert sound) simply sound better in the vocal frequencies than their equivalent two-way cabinet. Being very general here, but most of it probably has to do with the quality of components. A lot of two ways cross over from the horn to the low frequency driver in a range that greatly affects the vocal quality. By utilizing a third driver in that same frequency range, the vocals tend to sound cleaner/clearer to my ear than a typical two way speaker. Instead of making either the horn or low frequency driver work near the limits of their frequency response, the extra driver cleans up those frequencies. This all assumes of course a well engineered cabinet and effective crossover points.

 

[Petebass]

Yeah concert rigs are a different animal because quite often there's enough speakers in an array or semi-array that no one is really off-axis. That's hardly ever the case with small PA systems or standalone bass cabs, therefore an improvement in off-axis response is more easily noticed.

 

[KeithAlanK]

The band I play in uses Peavey SP4s on top and their folded horn single 18 subs.
Powered by Crown MacroTechs, this system is the best club sound I've ever used.
Period.


The trick with the SP4s is that the 2x15" Black Widows have a passive crossover between them at 250hz.
They sound surprisingly good when used fullrange (fried crossover, but it was just a wedding) but when used with good subs they really sing.
The bottom 15" only has to worry about 90hz-250hz, so I can dial in as much meat as I need and they'll never fart.
The top 15" covers the vocal and guitar range really well, up to 1.6Khz I think.
Without those lower frequencies making a mess with IM distortion, it does a really great job of staying clean and clear and articulate, while a 6 or 10" mid driver would have trouble handling the same amount of power.

Might as well mention the horn...
Very wide dispersion, especially compared to the EV and JBL tops I mix with other bands.
And the bottom of the horn slopes down at a much sharper angle than any others I have seen, so the people sitting in front can hear very well, instead of the highs beaming over their heads.

Other brands also have a passive crossover between the "low" drivers.
With subs added, you get a four-way system with just 2 amps.
Just because there are passive X-overs doesn't mean the sound can't be amazing, and you can still bi-amp them if you want.

I ran sound for a band that ripped out the passive X-overs and tri-amped their SP4s, and it sounded terrible compared to the way they were designed.
I warned them!
First band I ever quit in almost 30 years.
That says something for cabinets that are well-designed and built--2-way, 3-way, doesn't matter.
Sound is all that matters.