Looks interesting, but oh that price! No audition allowed, pay first then pickup!!!???
Ultra-Fi Altec 4x515B/Altec 288,1803B/JBL 075 HF horn driver - pair !!! For Sale - Canuck Audio Mart
Looks interesting, but oh that price! No audition allowed, pay first then pickup!!!???
Ultra-Fi Altec 4x515B/Altec 288,1803B/JBL 075 HF horn driver - pair !!! For Sale - Canuck Audio Mart
Wow those cabs are interesting too. Guess they weren't too interested in the fit and finish. Lol
Also isnt push/pull supposed to be setup with one woofer mounted correctly, and the other one backwards? Those are both backwards.
And finally, wouldn't that woofer setup be better for some car subwoofers, and not Altec 515's.
I would say the whole package is just worth what the loose parts are

Not especially well made home brew cabinets posted at about triple their worth. Yes, I need to rush out and but that without an audition.
Your neighbors called. They like your music.
Yeah, push-pull is normally one driver forward facing on the baffle and one reversed to cancel out even harmonic vibrations whereas clamshell is isobaric[k] loading that allows the cab to be significantly reduced in net volume [Vb] at the expense of losing the second driver's output, so normally restricted to either drivers that require huge cabs to go low like most Altecs or need super small cabs required for many mobile audio installs.
Since the 515B is dustcap ventilated, I have to wonder if these have been driven hard enough to heat damage the VCs; probably not due to system efficiency, but no test gear, audition for me = assume the 515s need reconing. Indeed, for me the only really high $$ item is the 1803s.
Have to wonder about the owner's hearing acuity as having done hearing tests on how high isobaric can be XO'd at high SQ as well as read quite a few on the forums pretty much limits them to a couple of octaves at most due to phase inversion, i.e 400 Hz with a 515 is pushing four octaves, so if nothing else the WLs are < the driver's Sd, so the frame is definitely adding harmonic distortion, if not outright whistling/chuffing background noises.
GM
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.

At least triple their worth. He's looking for a sucker.
Your neighbors called. They like your music.
I saw in the ad how they mentioned the 8x 515 woofers. I think its a very odd setup.
Like I said, I am used to seeing isobaric setups with one woofer facing in, and the other facing out. I'm not sure what they have is even isobaric. Seems like the cone area is the same as one woofer, when doubling the two up.
I'm more familar with isobaric cabs from my car speaker days. I tried it, and it does sound good. But I have never tried it the way they have in the ad
And like GM said, they might have overheated the VC's running them this way.
Again, one in, one out is push-pull, so designed like any other dual driver alignment whereas clamshell or one behind the other in a compression chamber is isobaric[k], with clamshell being the technically better performer of the two due to least trapped volume, though some folks claim [no clue myself] that push-pull isobaric is the best sounding [scroll down for layouts]: How to Build a Subwoofer Box | KICKER(R)
GM
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
I have experience with the push/pull isobaric but had never seen the clamshell version until this ad. Interesting
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