JE Labs style open baffles

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hello!

I have been playing with the idea to build as simple/minimalistic open baffles as possible (something like JE Labs style with only one FR element).JE Labs: JE Labs Open Baffle redux

I read that some of you have had good experiences with them, but I still need more info to determine if they are suitable for my purposes or not.

MJK style open baffles with 8" TB W8-1808 + 18" woofer is my reference so far:
+++Big, deep soundstage (lots of air between instruments), open realistic mids, suitable for many music genres, also for hard/heavy rock
---Bass quality (tightness, speed), upper mid/top end small colorations

These are my wishes for the new design:

- -6dB point approx 40...45 Hz
- baffle size not bigger than the original design (35"x31")
- must work with rock music also at moderate levels
- listening distance at small room max. 3 m (~10 ft)

Is there any change to succeed?
 
don't do it sounds like you have something better already

I made one with a 12" fullrange EV driver (high q for this model) with a tweeter added to the top. Bass was still weak.

The soundstage is too low. I changed the angle of the bottom of the side pieces to lay it back some more but ultimately built the MJK alpha/ 103 OB
Much better . the thing I did not like about the MJK OB was the jump
between octaves on bass instruments between the bottom of the speaker and the top. Bari sax for instance. other than that very smooth and easy to drive.
 
I did some modeling by using Tolvan Basta. According to frequency responce there should be decent amount of bass available in 50 Hz. But element location is not optimal, as far as I can understand. Please note that Basta does not take into account room boundary reflections. Only driver properties/location and baffle size/diffraction. Comments?
 

Attachments

  • Fane 12-250TC in JE Labs OB.pdf
    372.9 KB · Views: 134
Last edited:
I got some tips from finnish hifi forum to avoid that JE Labs (Briggs) style baffle. Someone had tested it with 8" Supravox and complained that soundstage was too low. At least when listened in small sized room. Maybe better solution could be a winged (folded) baffle with piano hinges, like wild burro audio Betsys. What you think?
 
Founder of XSA-Labs
Joined 2012
Paid Member
Try a slot loaded OB - it can get pretty deep bass in a fairly narrow baffle with multiple smaller drivers. Basically, you need at minimum a 15 in high Qts driver to get sufficient bass. You can do it with qnty 6 x 6.5 in drivers, qnty 4 x 8 in drivers, qnty 2 x 12 in drivers, or single 15 inch. The slot loading approach allows drivers to be squeezed in sideways reducing frontal profile.

I was able to reach 30 Hz with 6 x 6.5 inch drivers (Qts about 1).

http://www.diyaudio.com/forums/full-range/249984-cheap-fast-ob-literally-7.html#post3805024
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.