Open Baffle Sub?

[Mac 11700]

Ok...I guess I am a little dense about this..I read about these here..http://www.audiocircle.com/index.php?topic=70024.0
..but really haven't found any information I can understand..
Here's what they look like..


Does a twin sub arraignment like these really work as well as a full boxed sub? Can they dig as low and as loud ? I'm guessing they won't go as loud..but if high quality drivers and amps are used..like the servo type I've been reading about...wouldn't they sound much cleaner and accurate as opposed to a normal box? Would you have to have them set way out away from the walls like other open baffle speakers to sound the best..? I am needing a sub for my media room since I sold off one of my mfw-15's last July..With all the hub bub about these servo's has my curiosity up..and it doesn't look like it would be very hard to build one..

Has any one here ever heard one of these? I guess I could try to get in touch with Danny and see what he has to say about it..but I was just wondering what you guys thought about it..I am wondering if they would sound better than my mfw-15 I had in there

Mac

[dvenardos]

I am building these. Yes, you have to have them three feet away from the wall and open baffle subs are directional. The dipole radiation pattern looks like this:

http://paws.kettering.edu/~drussell/Demos/rad2/mdq.html

The sound eminates from the front and back of the open baffle and the nulls are to the sides. Since the sondwave is not omnidirectional like a boxed sub it also doesn't load the room so you aren't supposed to get stuff rattling off the walls and the exterior sound level is also supposed to be lower.

[dweekie]

Based on my experience with OB subs (not danny's), some general (but not absolute) trends seem to be much improved sound quality, much less perceived volume (room doesn't load), less low frequency extension, and less flexibility in placement (need to face you). I would not use OB subs in a home theater (without a significant number of drivers), but for music, the MFW would not be comparable at all.

[corndog71]

I haven't heard the OB servo subs so you can skip this comment if you wish.

I did build the sealed servo sub and it is one of the best subs I've ever experienced. It starts and stops on a dime. It does music and movies better than any other sub I've heard. Even while listening to music at low to moderate levels I can hear deep into the recording and any bass or drums are reproduced in jaw-dropping detail. When watching movies it can be downright frightening with how it energizes the room.

I read all about the OB subs and wanted to build a set but alas do not have the room for them at this time. Pity too as I live in an apartment building and would prefer not to load the room so much. I'm sure you've read the same reviews that I read about them and they've all been positive.

[woofersus]

The general commentary seems to be positively glowing, but as metioned above, OB subs definitely have to be out several feet into the room to work, and won't go "boom" so much. For music it would be great not to load the room, but I think for movies I sometimes want that thundrous earthquake effect. :) I can't comment on exactly how well they'd work for movies, but just from what I've read I think I'd probably do the sealed version.

A couple of people did a sealed dual 12" servo sub with 600w servo amp and they all seem to think it's the best sub ever.

[Mac 11700]

The general commentary seems to be positively glowing, but as metioned above, OB subs definitely have to be out several feet into the room to work, and won't go "boom" so much. For music it would be great not to load the room, but I think for movies I sometimes want that thundrous earthquake effect. :) I can't comment on exactly how well they'd work for movies, but just from what I've read I think I'd probably do the sealed version.

A couple of people did a sealed dual 12" servo sub with 600w servo amp and they all seem to think it's the best sub ever.

Well..allrighty then...this is info I am looking for...Sealed servo subs seems to be the way to go ...If they can give me both the slam as my mfw-15 and sound better with music...then it might be the way to go...OK...how much would it cost to build one of these beast..

Mac

[corndog71]

I built mine for around $600.

[Jethro]

Thats sweet man... probably as good as a bang for your buck system as I could fathom.

[dvenardos]

Depends on how much you want to do. I recommend elemental design for cabinet enclosures that are great to work with and can do flat packs, bare enclosures, or fully finished.

Well..allrighty then...this is info I am looking for...Sealed servo subs seems to be the way to go ...If they can give me both the slam as my mfw-15 and sound better with music...then it might be the way to go...OK...how much would it cost to build one of these beast..

Mac

[Cujobob]

I have a dual woofer OB servo sub and highly recommend it. I believe it would take four drivers OB to be equal to a sealed 15" in max output.

They are extremely easy to integrate with mains, but as mentioned require 3 ft. from a wall.

I don't think jumping up to the 600 watt amp adds much, but then I could have my subs mixed up.

Christof on AC did a nice job building mine.

[corndog71]

IIRC Danny said the 600w amp isn't necessary. The 370w amp is perfectly capable of doing the job with one or two subs. Either way you will get full extension down into the subsonic region. You could even connect a 3rd driver to the amp if it's an OB design.

[tortoiseman2542]

Christof on AC did a nice job building mine.

Would I be breaking forum rules if I asked how much that cost to have done by Christof? I wouldn't require any special veneer. Black would be fine.



Robert