[James Romeyn]

Will audition my friend's just-completed active triamped OB this Monday.  JBL 15 paralleled w/ JBL 12 (800 Hz LPxo), JBL 2397 mid horn lens (115dB!!!), tweeter unknown:




   

[JoshK]

Those woofers look like Altecs to my eyes.  But I could be wrong.

[James Romeyn]

Josh
I'm 99.99% sure he said both woofs are JBL.  I'll see/hear it Monday & will report.  I hope it doesn't sound as good as it looks because I just spent money on several drivers for a completely different kind of speaker project.  It looks great w/ the radial lens mid & tweeter atop...retro-modern mix.  W/ the grill attached the OB woof panel reminds me of a short cutoff old Beveridge stat.   

[androuski]

Could you tell more about enlosure ? They are kind of wharfedale sfb :

http://www.troelsgravesen.dk/Wharfedale_cat_files/SFB-3.pdf

 

[James Romeyn]

Josh
You was right; 15 & 12 both Altec, my bad  JBL mid & slot tweeter.

 Friend said all xo 2nd order, in-phase drivers.  Josh am I not right that when both hp & lp are 2nd order the resulting overlap range is 180-degrees out of phase w/ each other?  Friend said no, such applies only to 3/4th order, which sounded way hokey to me.  But I'm not about to argue such things, esp w/ a guy having an MEE.     

Androuski
I looked pretty closely at the enclosures but don't know how to describe it except to say it was indeed an OB.  Readers may recognize much more than I do about this because I'm not well versed on OB. 

I know the bass sounded great, shocking how low was the cutoff. 

Kinda didn't like the overall presentation to some extent though obviously great dynamics.  Think I prefer his other system w/ the box JBL 15/12, same mid driver w/ huge horn & same tweeter, passive xo. 

Anyway, I'm still happily moving forward on my ASA Pro Monitor bipole clone w/ design help by master Duke LeJeune; prototype enclosure due any day....5/8" particle board under 5/8 real russion baltic birch ply.

You've never seen so much random high end tube & other gear as in my buddy's 5500sf house.  It's almost mind numbing. 

[JoshK]

Josh
You was right; 15 & 12 both Altec, my bad  JBL mid & slot tweeter.

 Friend said all xo 2nd order, in-phase drivers.  Josh am I not right that when both hp & lp are 2nd order the resulting overlap range is 180-degrees out of phase w/ each other?  Friend said no, such applies only to 3/4th order, which sounded way hokey to me.  But I'm not about to argue such things, esp w/ a guy having an MEE.     

Altec woofers are cooler in my book than JBLs.    
I was under the impression that symmetric 2nd order slopes result in 180? phase shift too.  I thought that is why 2nd/3rd assymetric slopes were so popular.  I only know what I've read at this point, I haven't designed really any xo's.

[Unison845]

An update to Altec/JBL Open baffle.

The ALtec 416 has been replaced with Supravox Field Coil, the ALtec 414 replaced with TAD 2001 an 500Hz 12 in horn. JBL 2440/horn and tweeter reomoved. This OB now become a 2 way.

[James Romeyn]

Why, why, why is this hobby so much fun? 

"Unknown and unknowable," me thinks, as my friend/PhD/retired philosophy instructor is fond of saying!!!!!

Everyone have a happy thanksgiving!

Check Duke's AudioKinesis forum for our art exhibit music/audio show/food charity this coming Saturday in Logan!  The best audio/music show ever in Utah! 

   

[Unison845]

An Open Baffle Hartsfield.