AV-15 tuning frequency opinions (1 Viewer)

[Brian-K-Owens]

Hi,

My friend and I built the sonotube for his AV-15 this weekend.

Here are the specs:

Internal NET volume is 235 liters (8.35 ft^3).
Right now, the port tuning is at 18-18.5Hz.
Stryke 350 watt plate amp, bass boost removed (so no subsonic filter).


I am wondering about the port tuning. Can I increase the tuning frequency to 19.5-20 Hz to get a little more output between 20-40Hz, or is it a better idea to leave it lower, since there will not be a subsonic filter? Will he even notice a difference with a change that small?

Thanks,
Brian Owens

 

[Jack Gilvey]

I'd bet that there's no way you'd notice a difference between an 18Hz and 20hz tuning since room effects tend to overwhelm "graphs" down there, and certainly not between 18.5Hz and 19.5Hz. As you say, the lower tuning will offer slightly more woofer protection below Fb, while the benefits in excursion and output above Fb with the higher tuning appear quite minimal.

 

[Brian-K-Owens]

Thanks Jack!!!

We actually finished the project on Monday night. Left the ports tuned to around 18 Hz.

It sounds AWESOME!!!!! The amp350 plate amp will get it really loud, but it could handle quite a bit more power. Might have to look at an external amp later.

Lower end response is great!! The guy I built it for is replacing a Polk PSW650, and the AV-15 setup makes the Polk sound really bad!!!

Brian

 

[Jack Gilvey]

Cool!

If you did eventually get a pro amp for it, you'd definitely want to add an infrasonic filter also...more power would be too dangerous without.

 

[FredC]

I will be building a sonosub with the same components. I'm just curious if you mounted the Amp to the sub and how you did it. I've been contemplating mounting a box to the side of the sonotube so I dont have to cut into it.

 

[Brian-K-Owens]

I cut a hole in the tube and mount the amp to the side.

When I cut the sonotube caps out, I cut one of the caps in the corner of the sheet of wood in the correct position to allow me to use the "scrap" wood as the top and bottom of my amp mounting plate. That is hard to describe. . . see what I am saying? The leftover wood from the cap cutout is already the correct radius to mount on the outside of the cap, so if it cut near a good straight edge, most of the work for the amp mounting "box" is done!!

Hope to get a couple of pictures of the AV-15 and my tumults posted soon.

Brian