PA Speakers DIY

[ZilchLab]

Originally Posted by MrMagnus

How do You guys think of the DR300 when it comes to rooms less than 100 sqm?

"DR300s are narrow dispersion long throw cabinets and are not recommended for use when the minimum speaker to audience distance is less than thirty feet, nor for venues with less than 800 seats."

[technofreak]

Well, I don't like billfitz designs that much - DR300 does it all wrong (IMO) - folded horn for mids, compression driver horns mounted the wrong way (giving 40 degrees horizontal and 90 vertical dispersion, and there's two of them, combing is inevitable). OmniTop 12 look a bit better, but you should REALLY throw out the piezos and use a good 1,4" driver with a good horn - BMS 4554 plus 18sound XT1460 is a good choice here - and cross actively around 1,3 kHz. And then you need to go 4-way and add a kick bin between sub and top to fill in the 80...200 Hz range.

If the sound quality is the most important, go for 3-way tops - a 15" bass, 6,5" or 8" mid and a small compression driver. This combination can be used without subs if needed and can have truly hi-fi sound quality. For 6,5" mid Ciare 6.38MR 3 is a suitable candidate - sensitivity of over 100 dB, can be used from 500...5000 Hz and keeps up with a 15" bass easily. For horn, Eminence APT80 is tested and good. For bass almost every mid priced 15" with more than 3 mm Xmax, Qts of around 0,35 and power handling of 400 W will do. Cross 15" to 6,5" actively and use simple passive xover for the mid-top section.

As for subs, I don't think that bill's designs are the best out there either (but they use cheap drivers), plus you need to use at least two coupled together to get anything useful out of them (I don't trust the FR graphs there too much). I'd go for 18" or double-18" (the latter in push-pull configuration, of course) for scalability - take one for a small birthday party, 16 for outdoor concert. This is because they get only louder if you add more. Horns go louder AND deeper, since they're compromised in size to be moveable. Thus they are too small to work correctly in singles.

[MrMagnus]

Well, was a bit to eager and fast but then found that the other option was more suitable in my case (even tho the DR300 would be great for outdoors, also a feature I would like).

[paulspencer]

Mr Magnus,

Here's my suggestion. If you want to design your own from scratch and that sounds like fun, then go active. Otherwise you could build a clone of an existing design.

For your own design, you want a basic measurement setup like this:
Red Spade Audio: Basic measurement setup

For a low cost active xo, MiniDSP ... all the active options discussed here:
Red Spade Audio: Active options

Drivers and box ...

I'd go with a B&C compression driver in a 12" conical waveguide from PE

along with a decent 12" mid with a nice flat response. Perhaps a B&C one of their mid priced drivers, I'd aim for better than most Eminence drivers.

Then I'd add a pro style sub with some 15" or 18" vented woofers. The advantage of the 3 way is that you quickly and easily get "fun bass" with a higher level.

BTW, any of the Geddes kits would be ideal although I won't insult them in saying they are a party speaker.

[sapi]

Hi
here you can find some PA-like hifi speakers or is it Hifi-like PA speakers Hifimaailma.fi - Artikkelit
The text is in a strange language, but I'm sure the schematics and measurements are understandable.

Cheers,
Pasi

[MrMagnus]

After some more researching in PA I have chosen to go with building modules.
At the moment I am looking in to 3- or 4- way system.

With a box with sub = lower mid, a Box with upper mid and high is what I have in mind.