Open Baffle Opinions - I Won't go back to Boxed Speakers Evr Again (maybe....)


https://photos.app.goo.gl/cg64ScibP75b1YVF6

My very last DIY effort after doing the DIY Speaker thing (for myself only) for 35 years (only 5 pairs built in that time). These are my best effort WRT to sound quality. Bass down to 30Hz, sweet treble and midrange to die for.

All Parts Express Drivers. GRS Planar, GRS 12" (Qts = 1.27) Woofers, and Dynavox 5 1/4" midrange/midbass Drivers. All in $600. Still some tweaking to to on the Cabinet and the Crossovers. A simple 1st Order 16uF Sonicraft Capacitor on the Tweeter and a 2nd Order Bandpass on the 3 Dynavox Drivers. The H-Frame Woofers section is powered by an ICE Power Class D (1000W@4 Ω). Two for stereo of course. MiniDSP dialed in for a 250Hz Linkwitz-Riley 4th Order LPF, the Bandpass is 250Hz - 2500Hz, and the Magnetic Planar BG knockoff by GRS takes over at 2500Hz. No L-Pads anywhere !

My question is what is the Phantom Center like ? Mine is not as focused as I’d like it to be. But my God, the soundstage, imaging, front to back depth is amazing. Clarity like I’ve never heard before form a Box Speaker and the Bass is like I’ve never experienced. No Box Boom. 40Hz all Day and I can hit 30 Hz with very little attenuation

rajugsw
  1. Build a box around just the Midwoofers leaving just the 12" Woofers and the Tweeters Dipole. Changing the crossover points from 250Hz - 2500Hz to 120Hz - 2500Hz won't be hard. I have lots of Inductors laying around that I can cobble something together. Lowering the 12" Woofers LPF to 120Hz is a snap with miniDSP.
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man you are way ahead of my DIYer skills. I have no idea what you are talking about. 
However , though i do lack the science and deeper understanding of these things,,does not mean i am not willing to do some DIY stuff on my own. 
I just shipped back the Seas Fa22rcz after 15  minutes of testing .
So I am back to the drawng board,
Going witha  Davidlouis Lowther/Voxativ clone. The 2020 version,  the 8 incher. 

so my New Thor design will be dual W18 E001's + the Lowther/Vox clone 8. 
Adam at Madisound on <my> new Thor said of it,~~sounds like you got a  real Frankensteinspeaker going on there~~~lol, Yep, hope the 87db midbass pair up well with the 95db FR..


jimob
18 posts
05-10-2021 8:16pm
I have owned 2 Spatial audio labs speakers ,and currently
saving for the Exceptional X3s. They have a great minimal Xover only 3 parts, the CustomBeyma AmT midrange-Tweeter,is excellent and there is no Xover in the critical midrange from 1k on up , very efficient 97db-1watt, 12 inch mid bass , and from 90 Hz down to 25 HZ and is powered for deep clear Bass.


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Sounds really nice what you got going on there.

I just cked out Beyma's cp750TI horns, weighing in at 15 lbs each!!!!
Really nice, 
But have to pass up these massive  and tempting , horns. 
Staying with a  FR + midbass design. 
The FR goes up into the 10k-15k range, and thats all I need.
I have no interest at all past 15k as 99% of classical music has nothing at all past 15k.
Sure a horn goes right up to 20k. 
But for what purpose????
zero interest. 
As well  these  , high tech compression mid tweets , have incredible sensitivity at 100-120 db sens. 
Again for what purpose??
My amp is a  true 100 watt PP.
On midrange/highs I look  for 94/95 sens. Even 97db is too high. 
I listen extremely near field in my small room  , so anything higher than 95db is a overkill.

Over 95db on a  full range, this would mean gain on the linestage would be set very low, which would not allow the W18E001's to open up..
The dual W18E001's are acting like a  bass floor for the Full range.
Really  is a Frankenstein of a  speaker
I havea  pair of open baffle,, well honestly, they have 1 screw hopding the driver to the top of the Thor cabinet,, The Millennium spot is now open as a  front baffle, , took out most of the stuffing fill and placed a 1 inch pad behind each W18/
Lots of bass and sounds super. The Diatone 6.5 is far superior to the Millennium tweeter for full rich midrange/highs. Even a bit lo nice solid upper bass. 
We need to begin thinking outside the box. 
I should have made this Frankenstein pre-upgrade on the Thors. 
The loss in that upgrade project  really pushed my bottons and I came up with this New Thor design in frustration and despair. 
Suffering is the root of creativity. 

I don't process some of the technical jargon in this post but isn't the open baffle concept what the Dahlquist DQ 10 was trying to accomplish?  I own a pair and they sound fabulous..  Just curious....
Very fun and interesting project you've done!

If the three drivers were sealed as stated above, based on the specs for the drivers, they will naturally have an F3 of 130hz, with a 0.105cuft which should make crossing over at that point quite simple.  With a QTS for these drivers being .34, and an EPB of 137, I think they could benefit from being boxed in. Although, they would prefer a ported design, which is not a good idea for an OB speaker :)

Would be very curious to see what the difference would be having the 3 drivers in the same sealed cabinet vs having them in their own sealed enclosures. 

I'm a bit confused as to the reasoning behind the H frame and how it dissects the top woofer. Asking because I have been wanting to build some open baffle speakers for myself, but 4x15" woofers, 2x6.5" full range drivers and a (possibly) rear firing super tweeter (not to mention crossovers) they can get quite costly as an experiment.  The wings and associated math to sort out baffle step is something I have not wanted to take on quite yet either.

Decwares approach with the curved edges is an interesting design approach, but again, either math, or a LOT of wood being cut to experiment with.


@bdp24 , @atmasphere - I have also found that moving the speakers further into the room and adding some diffusion behind the speakers helps a lot with the imaging and soundstage. I have two 2x4' GIK panels with diffusor plates behind each speaker and have the speakers placed such that the front of the baffle is about 7ft from the front wall.  This creates a deep sound stage with nicely focused imaging. I wouldn't say it's the sharpest imaging I've ever heard, but I really like the overall presentation. 

@sejodiren - yes the DQ10s were one of the first speakers to popularize open baffle, although these speakers used a conventional box enclosure for the woofer.