DIY Open Baffle Info Needed

I like building HiFi speakers. Recently I became enthralled with the concept of open baffle. Where can I find concise information on what specifications I should be looking for with regards to a 10" or 12" full range or coaxial driver? Any recommendations for drivers around $150 each? Are there any online DIY plans or websites I should be looking at? Thanks in advance!


2008-02-22 1:21 pm
You will find a lot of info by using the search function in this forum or Multi-Way.

My understanding is it boils down to this: the driver playing bass should be as large as allowable (high Sd), have a high Qts (>0.7 - opinions vary...) and substantial excursion capability (high Xmax). A single 10" or 12" certainly is possible, but you'll open-up choices if you go with a 15" or 18" bass driver and cross-over to pretty much any driver you like above this.

Here's something to start with:

I can't claim to keep up to date with OB design, but I think the above should still mostly stand.
Thank you so much...The little research I've done, I'm thinking a 10" full range or coax speaker to limit the baffle size and increase frontal dispersion and augment with one of my subwoofers (SVS or B&W). I recently bought KEF LS50 Metas and became a believer in Point Source technology. Eminence makes a series of speakers with screw in, coax mounted compression drivers. Much like Zu loudspeakers use. Would these be appropriate? Specs here... Or could I get away with some type of driver with a simple wizzer cone and DIY a coax mounted tweeter?


2008-02-22 1:21 pm
If you plan to use box subwoofers, you open baffle's width will still have to be made wide enough to meet the highest frequency reproduced by the sub. While a bass-only OB woofer can have baffle extensions such as U or H frames to look slimmer, doing so with the mid/high driver risks introducing reflections and diffraction.

I have no experience with the Eminence coax, but they should likely be decent enough. I'd go for at least ASD1001, preferably PSD2002 for the highs, if not something from another brand entirely. Since this is the fullrange forum though, I will say that any good fullrange should do very well on OB if properly relieved of bass duty. Just avoid the super-low Qts units, below 0.35 or so, which might struggle to reach down to the sub even on a suitably large baffle.


diyAudio Moderator
Paid Member
2004-10-07 6:05 am
SW Florida
I will say that any good fullrange should do very well on OB if properly relieved of bass duty.
I agree. I've used all sorts of fullrange drivers on OB (with 15" woofers underneath). I've used and heard many; from Vifa to TB to Wild Burro, Hem,p Saba greencone and even car speakers. All sound different but work well if high passed and supported with a woofer.
It is very easy to make open baffle speakers - too easy at first glance.

But it is very difficult to make GOOD open baffle speakers, that have controlled dispersion, smooth response and low distortion!

Some examples of both extremes and something in-between here

Rbertalotto, please think more deeply about our goals - what size, what frequency range, what spl max, passive/active, analog/dsp etc.