Poultrygeist
Lunatic Member
I had these OB Tektons on long term loan and had lots of fun with them. The little Fostexs were so detailed but without the H-frames there wasn't enough meat on the bone. Eric at Tekton sells dual subs for these OB's.
Open Baffle Epiphany!
- Thread starter cptnCanada
- Start date
Most of the compression drivers I have, there is just a cover with a thin piece of foam in it covering the rear of the diaphragm. Remove the cover and the diaphragm's rear surface is totally exposed.
Mister Pig
Pigamus Maximus
Here is a close up pic of the back of the coax speaker with the Radian diaphragm visible. Sorry for the pic, the ambient light sort of fuzzed things out.
Here is a pic that's a bit better, and you can see how the back of the co ax driver is arranged.
Regards
Mister Pig
Attachments
To get the maximum gain of mutual coupling, you would normally want the driver pair to be as close as possible. The distance that's acceptable is dependant on the frequency you run them up to. But with that small of a driver for the top end, I'm thinking you'll be needing to run the woofers up pretty high so that suggests getting them cozy.
No need for a big gap to the top end driver either as more energy is present further from the crossover point than people realize. The greater the distance, the further you have to be from them to not hear them as distinctly seperate sources.
Different people feel differently about how low to have the woofers. Some want the gain from being close to the floor. Personally, I dislike the coloration of the bump of that gain and I prefer more distance. But getting the mids towards ear level is pretty generally accepted as a good target.
Using lower Q woofers means you'll probably want to be able to add some eq in some way down lower to compensate for the tighter movement at resonance. As long as the driver can move that far and you have the power to push it, that's the route to work on.
Good luck with it and get the cuttin' done so the music can flow!!
EV3
Tasty MP! I had not run across that option of the open back for those specific drivers that way. Though I had heard of taking the back off CD's.
If and when I ever get time to finish it up, I'm going to have a mono stack of 6 of the 15" Augies for LF on my OB rig.
Don't think it'll be as pretty as what you've got there though. I had just spotted your Hawthorne thread in the last couple days. Very nice....EV3
Poultrygeist
Lunatic Member
These B&G Neo3 planar tweeters are a good choice. For use in OB's they require removal of the back covers which are designed to come off with a little pressure.
mhardy6647
Lunatic Member
everything is designed to come off with a little pressure. All guys know this; it is in our genes
;-)
;-)
Mister Pig
Pigamus Maximus
That is still of little solace if you have been triple dog dared to stick your tongue to that flag pole......if you were unwise enough to accept that challenge.
Regards
Mister Pig
jhoyt
Incomprehensible space llama
Our esteemed brother Red Green would surely agree. :yes:
tomlinmgt
Lunatic Member
Here is a close up pic of the back of the coax speaker with the Radian diaphragm visible. Sorry for the pic, the ambient light sort of fuzzed things out.
Here is a pic that's a bit better, and you can see how the back of the co ax driver is arranged.
Well how 'bout that...here I've been thinking all along cd's can't propagate a rear wave (clearly this noob still has plenty to learn). I took at look at my Radian 475PB's and the back cover is plastic. I peeked under the emblem/model badge on the back and it's solid. But it looks like your's is the same as mine, but with a hole. I wonder if I could get an open back cover plate like yours from Radian? :scratch2:
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Mister Pig
Pigamus Maximus
Well how 'bout that...here I've been thinking all along cd's can't propagate a rear wave (clearly this noob still has plenty to learn). I took at look at my Radian 475PB's and the back cover is plastic. I peeked under the emblem/model badge on the back and it's solid. But it looks like your's is the same as mine, but with a hole. I wonder if I could get an open back cover plate like yours from Radian? :scratch2:
I think you are going to have to buy another closed back and open it yourself. The ones I got with my speakers are an upgrade option, and the price is a bit outrageous for what they are. I can't complain, I didn't pay the asking cost for them. There is a screen across the opening, and it is held in place by a large o-ring.
Regards
Mister Pig
tomlinmgt
Lunatic Member
Hmmm...so I was kickin' around the idea of trying an open backed Radian in a QSC 152 with a TD15M covering mid range in an OB with one (or two) IB15 covering 80-ish and down....just to play around a little. I guess that wouldn't work since I sure can't play the Lambdas up as high as you're suggesting, Dave. I suppose I'll just try it with monopolar HF.
tomlinmgt
Lunatic Member
The screen covering the Ti tweeter in my L100t's was secured the same way. Clever, but kind of a PITA to get on and off.
Mister Pig
Pigamus Maximus
Buy yourself an extra set of backs, cut them open and experiment and see what you like. You will have a bit of a chance in experimenting with crossover points if you want. I have listened to both arrangements, and prefer the dipole back. Yes the speaker is a bit softer, but when I weigh all the positives and negatives, well I take the dipole arrangement. All in all it is a pretty cheap endeavor, and then you know.
Regards
Mister Pig
tomlinmgt
Lunatic Member
My observation about the o-ring secured screen was more trivial than anything else. I surely wouldn't let something like that stand in the way of realizing sonic superiority. My issue has more to do what Dave alluded to...namely the higher xover point required to avoid having to EQ the Radian.
Poultrygeist
Lunatic Member
Not unusual to see surgery performed on the rear damping chamber for use in OB. Here's an example in the Emerald Physic's clone build.
http://www.tweakaudio.com/EVS-2/Modding_the_Emerald_Physics_spe.html
http://www.tweakaudio.com/EVS-2/Modding_the_Emerald_Physics_spe.html