Recommended 15" woofer for Open Baffle


2013-09-07 10:39 am
Hi everyone!
I prepare to build own Open baffle, but have problem which woofer should I use.
I consider choice between Eminence Beta 15A and PRV Audio 15W700

I read a lot of about Eminence but I can't find opinion about PRV in open baffle.
Which one in your opinion is better? or maybe you have other recommendation?
Which IS better?

Interesting question... you can make a case for either one, assuming their costs are roughly the same. Over all, assuming a passive crossover, the PRV has more potential. I am also assuming the published specs are representative. The big advantage for the PRV are xmax, cone area & a narrower break up peak. Disadvantage is lower QTS which could mean more low end crossover correction. Interested in your overall plans - goals. Knowing them I may be able to comment further. Good luck!


2013-09-07 10:39 am
I'm thinking about 2 woofers per side, on top will be fullrange Alpair 12p or Lowther PM4 (I have possibility take both for tests). I'm planning use active crossover (eg. miniDSP) with 2a3 tube amp over 250Hz.
As you said T/S parameters in specs looks good but I don't understand plot of characteristics and I can't compare this one with characterisitcs from Beta.
What conclusion?
For open baffle it is generally preferable to look for

  • high Q (-> cheap, more bass spl without equ.)
  • low fs (-> deep bass)
  • high excursion (-> more dynamic, deep bass with more spl)
  • as big as possible membrane surface

You can ofcourse also get excellent results with different Chassis too but with that combination it's the easiest and cheapest.
I have just bought a Gladen RS15FA. It has 16 mm linear Xmax one-way. It can take a lot of power, and have Fs below 30 Hz, and Qts around 0,5 (can't remember).

The build quality i superb, and the price is very reasonable. I gave 190$ in Denmark.

One thing to remember. To get som bass from an open baffle, you need some excursion, and you need a solid build woofer, that do not have mechanical noise, when its moving. Not all woofers can do this. I have eight 10" Vifa woofers right now, and they suffer from mechanical noise, when moving a lot of air.

I will test the woofer this weekend.
Low Fs is essential for OB, if you want it to play deep. I have DSP and plenty of power.

Overall sensitivity at 85 dB is not bad at all.

There is no best woofer for OB. If you have small amps and passive filters, then requirement are different than if you have DSP and big amps.

Basic requirements are
Solid woofer with good ventilation through magnet.
Adequate Linear X-max - at least 6-7 mm one way.
Low enough Fs to meet your requirements - Do you need 40 Hz or 30 hz. Do you plan for a "real" open baffle or slot loaded.

Linkwitz have his opinions and Martin King has different values he favors.


2014-07-16 7:49 pm
Room lenght defines more dipoles low end than Fs.

Modified deltalite is darn good, silent motor on every angles, plays 30hz reasonable levels even naked (6m room lenght)
I know - I do measure distortion when I eq, and use it to set filter. Right now I have to filter away anything below 35 Hz, and keep SPL at normal listening levels. With the Gladen 15" - I will be able to play about 6 dB louder (simulations show - but I still haven't measured).

A taget of 40 Hz is not mine - It's ok but not real fun. I need 30 Hz.