604 dispersion characteristics

[thinking]

OK, this has irritated me long enough, and I'm going to get it unloaded. I won't go back and find the previous posts that refer speciffically to the fact, but it has been noted a number of times that one of the drawbacks of the 604 is the changing directivity with respect to frequency. That is, the highs are controlled, and the lows are not, resulting in undesired LF reflections from surronding walls, etc.
That all makes sense (although I've personally never been bothered by it) and then Parts Express features a creation on the cover of their current catalog, and on their website.
Parts Express DIY Project
So we have someone touting the wonders of their creation, that it is omni directional for the lows, and directional for the highs, and to add insult to injury, they are crossing it at 1560 Hz, almost exactly the same as a 604. So what gives, why is this so great, and with the 604 it's a drawback?

[klausesser]

OK, this has irritated me long enough, and I'm going to get it unloaded. I won't go back and find the previous posts that refer speciffically to the fact, but it has been noted a number of times that one of the drawbacks of the 604 is the changing directivity with respect to frequency. That is, the highs are controlled, and the lows are not, resulting in undesired LF reflections from surronding walls, etc.
That all makes sense (although I've personally never been bothered by it) and then Parts Express features a creation on the cover of their current catalog, and on their website.
Parts Express DIY Project
So we have someone touting the wonders of their creation, that it is omni directional for the lows, and directional for the highs, and to add insult to injury, they are crossing it at 1560 Hz, almost exactly the same as a 604. So what gives, why is this so great, and with the 604 it's a drawback?

Hi!

To be honest: this is a literally needless design in my eyes. Maybe nice for people living in a designer-designed house and having more money than they might have taste . . . . ;-))

Under audio aspects . . . http://www.hostboard.com/forums/images/icons/icon13.gif
Thumbs down

"So we have someone touting the wonders of their creation, that it is omni directional for the lows, and directional for the highs,"

sensational . . . . :-)))



best, Klaus

[GM]

Hmm, AFAIK, I've been one of the most vocal around here about the polar patterns of the models with the smaller horn/higher XO point and where these have audible shortcomings compared to the early larger horn/lower XO point models, the PE project OTOH apparently does an excellent job of balancing the design trade-offs/minimizing the transition anomalies from omni to beaming of a multiple point source system, so to my way of thinking you're comparing 'apples n' oranges'.

This doesn't make the HOSS's collapsing directivity 'good' per se though, just that when choosing to use multiple point source drivers to cover a wide BW it's automatically considered an acceptable trade-off, so the performance criteria is reduced to how smooth (transparent) it is. Most of the 604 models OTOH don't do so well, so in this regard I imagine the HOSS is superior, though without polar and impedance plots combined with BW limited listening tests there's no way to know for sure.

GM

[klausesser]

Hi GM!

I came across dozens of those "stylish" designs - being "stylish" is their most remakable feature in 90% of the constructions. None of them lasted longer than some seasons and all sounded the same way: hifi-like.
(in my eyes and for my taste the design is terrible - but that of course is very personal).

Using a usual mid-range conus and a usual HF dome in combination with a subwoofer per side still is a "usual" system. The way HF-dome and MF-come are assembled looks very elaborated - but in fact it?s still a MF-cone and a HF-dome. With much more dynamic-limitations than a 604 in any incarnation.

There really are more interesting and more elaborated constructions - which use very advanced materials and assemblies to build a point-source of very high precision - and an efficiency of 90dB having ALL freq. from 180-25000hz from ONE point of about 18cm diameter.
My experience shows that as the only consequent way to reach for a "natural" directivity.

as an example: Manger Schallwandler

Maybe i?m a bit unfair and completely wrong - it?s just my impression.

best, Klaus