Stick with my AV15, or upgrade to the TD18H+?

[littlepucker]

I can't argue with much of this, but if you're going to be a dick, here's proof that i did EXACTLY what you told me to do:
http://www.aespeakers.com/phpbb2/viewtopic.php?f=2&t=1720

My enclosure is 3.5 cubes tuned to 25 Hz. Port is 14.5" x 2", therefore 29 inches^2.

You will lose this battle.

 

[John_E_Janowitz 10+ year member]

I can't argue with much of this, but if you're going to be a dick, here's proof that i did EXACTLY what you told me to do:
http://www.aespeakers.com/phpbb2/viewtopic.php?f=2&t=1720

My enclosure is 3.5 cubes tuned to 25 Hz. Port is 14.5" x 2", therefore 29 inches^2.

I apologize. I thought when you actually built it you ended up going much smaller than that. The 14.5x2 slot port should be good for up to around 1000W input before running into much port compression.

John

 

[kendogg 10+ year member]

You will lose this battle.

If only you knew some of the people I know,and some of the things I know //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

Unfortunately, I'm not an engineer, so I'd have to hand the laptop over to my engineer friend with a physics degree to correctly word it to prove a majority of ^^^^ is bullshit. Basically, you'd need to measure everything in the car, and would have to plot out a graph of all the known info, including the electrical sine wave in milliseconds, to have any idea if there's really any significant cancellation. And I have plenty of new info as to why the sub does a few of the quirky things it does, but I'll keep them to myself. Moral of the story - if it seems to good to be true - it probably is.

But like I've said - I've learned my lesson,and I'm sure nobody wants to hear about any of the shortcomings of their wonder subs //content.invisioncic.com/y282845/emoticons/rolleyes.gif.c1fef805e9d1464d377451cd5bc18bfb.gif

 

[John_E_Janowitz 10+ year member]

Unfortunately, I'm not an engineer, so I'd have to hand the laptop over to my engineer friend with a physics degree to correctly word it to prove a majority of ^^^^ is bullshit. Basically, you'd need to measure everything in the car, and would have to plot out a graph of all the known info, including the electrical sine wave in milliseconds, to have any idea if there's really any significant cancellation. And I have plenty of new info as to why the sub does a few of the quirky things it does, but I'll keep them to myself. Moral of the story - if it seems to good to be true - it probably is.
But like I've said - I've learned my lesson,and I'm sure nobody wants to hear about any of the shortcomings of their wonder subs //content.invisioncic.com/y282845/emoticons/rolleyes.gif.c1fef805e9d1464d377451cd5bc18bfb.gif

I'm not sure what you're claiming is BS, but that's ok. You don't have to plot out anything to know if there is a cancellation. You adjust the phase on the amp and year it, or measure it. People often try to apply math to things and do difficult calculations that are much easier done in the real world than on paper. But yes, cancellations from phase not being coherent are a big issue in majority of vehicles, home theaters, recording studios, live sound applications, etc. This is why processors have both time delay and phase adjustment as both need to be correctly setup.

Anyway, I would love to have info on the "quirky things" the woofer does and know about the shortcomings. I have had nobody else have any of these issues, but if there are legitimate problems with the woofer I would of course like to deal with them appropriately. Send me a PM or IM and let me know what your findings are or feel free to post them here.

One other interesting thing I found regarding the AV series was actually measurements posted back in october last year. The first of the AV woofers went to AV123 for use in their UFW12 subwoofer upgrade. Mark Seaton did very thorough testing on it as you can see in his results here.

http://www.av123forum.com/showthread.php?p=672192#post672192

Again notice the midbass, very flat to well above 100hz. When the limiter on the 1000W amp kicks in to avoid clipping, there is virtually NO power compression.

John