ARCHIVE Feeler-Group Buy 80-Series 10" Sub Mount

[aviator31]

I have mine mounted and installed, but I tried using the shallow mount Kenwood that I already had in a box. Doesn't work too great, so I suppose I need an actual FREE AIR sub to make it sound decent. I'm not looking for competition sound, just some ok bass to finish things off. I'm very happy with the bracket and install, but I'm also trying to figure out how to make it all work/fit with the factory plastic panel. Do I simply cut a big round hole in the plastic panel and mount the speaker through that with a grill? Thoughts?

 

[nukegoat]

Free air subs have different suspension to prevent them from self-destructing, but acoustically you still have to isolate the wave coming from the back of the sub from the wave that comes from the front of the sub.

http://en.wikipedia.org/wiki/Comb_filter

 

[Finnyfam60]

Free air subs have different suspension to prevent them from self-destructing, but acoustically you still have to isolate the wave coming from the back of the sub from the wave that comes from the front of the sub.

http://en.wikipedia.org/wiki/Comb_filter

Way over my head.
How about a suggested solution instead of just pointing out the problem?

 

[nukegoat]

Way over my head.
How about a suggested solution instead of just pointing out the problem?

The sub needs an enclosure, not a mount.

 

[aviator31]

Way over my head.
How about a suggested solution instead of just pointing out the problem?

That's what I'm saying! What's the solution or is there not one?

 

[landcrshr]

What we have in that rear quarter panel is not a free-air situation, it's more like an imperfect enclosure. But in any case you need to completely isolate the front from the back as nukegoat said, otherwise you will diminish the low frequencies (high-pass filter, not a comb filter).

My guess is this would be the best approach:

Do I simply cut a big round hole in the plastic panel and mount the speaker through that with a grill? Thoughts?

And don't use a mesh grille, use a more open "waffle" style grille.

 

[aviator31]

What we have in that rear quarter panel is not a free-air situation, it's more like an imperfect enclosure. But in any case you need to completely isolate the front from the back as nukegoat said, otherwise you will diminish the low frequencies (high-pass filter, not a comb filter).

My guess is this would be the best approach:


And don't use a mesh grille, use a more open "waffle" style grille.

Wish I would have known this wouldn't work before I wasted $100, oh well ya live & learn.

 

[landcrshr]

$100 for the sub mount?
You would still use it, just load the woofer outside of the panel.
You may need a spacer behind the panel though.

 

[nukegoat]

What we have in that rear quarter panel is not a free-air situation, it's more like an imperfect enclosure. But in any case you need to completely isolate the front from the back as nukegoat said, otherwise you will diminish the low frequencies (high-pass filter, not a comb filter).

My guess is this would be the best approach:


And don't use a mesh grille, use a more open "waffle" style grille.

The wave interaction from a speaker without an enclosure (or, more specifically, an imperfect enclosure) will have phasing interactions that resemble a comb filter. If you low-pass the sub enough, you may only see the cancellation part of the combing, but it'll still be a problem.

Cliffs: Acoustics are more complicated than kinematics

 

[landcrshr]

A true subwoofer is after all defined by a very low low-pass band.

I think phase interactions would be caused more by the flimsy plastic panel flexing in and out than by any "leakage" from front to back.

But then, I don't think this mounting idea was ever intended to be a high-end solution, just an upgrade over the inaudible little stock job.

 

[ewillis]

$100 for the sub mount?
You would still use it, just load the woofer outside of the panel.
You may need a spacer behind the panel though.

This kinda pisses me off as I have one sitting in the garage ready to install. I wonder if I could modify the plastic from a used 10" base tube (maybe like 4 inches of it) to mount a true sub using the bracket somehow. This might give it enough space and density to get a decent thump when coupled with the space behind the plastic. Thoughts...?

 

[nukegoat]

This kinda pisses me off as I have one sitting in the garage ready to install. I wonder if I could modify the plastic from a used 10" base tube (maybe like 4 inches of it) to mount a true sub using the bracket somehow. This might give it enough space and density to get a decent thump when coupled with the space behind the plastic. Thoughts...?

If you want to get creative you can fiberglass an enclosure of the right size or do your idea with an aperiodic membrane as close to the back of the driver as you can get, but you still need to isolate it.

 

[ewillis]

If you want to get creative you can fiberglass an enclosure of the right size or do your idea with an aperiodic membrane as close to the back of the driver as you can get, but you still need to isolate it.

I've worked in the seismic retrofitting field as well as aerospace using carbon and glass; making an enclosure would be a beeach! I think the bass tube might work. Are you saying that the tube should just reach beyond the magnet and then attach the membrane over the end of the tube (closest to the magnet)?

 

[landcrshr]

...or do your idea with an aperiodic membrane as close to the back of the driver as you can get.

That claims to be a technique to flatten response in a small enclosure, but it comes with a price.

"...The trade off here is a decrease in output in the bottom octave."

Taken from this article (which, from what I read, isn't entirely accurate): http://www.teamaudionutz.com/tutorial/1/AP_Enclosures-The_Aperiodic_Cookbook

 

[RS6tofj80]

That claims to be a technique to flatten response in a small enclosure, but it comes with a price.

"...The trade off here is a decrease in output in the bottom octave."

Taken from this article (which, from what I read, isn't entirely accurate): http://www.teamaudionutz.com/tutorial/1/AP_Enclosures-The_Aperiodic_Cookbook

 

[RS6tofj80]

Like Many I have limited expectations for the level of base but don't really need much more.... so I started my instal today....

I'm using the 5th channel of my Kenwood 5 channel amp that sunder my river seats to power this - dedicated 400 watts with the wire run under the carpet and into the rear area.... I've already done most of the fattmatt in the compartment....

I also picked up a spare plastic panel as I plan to cut it up and also add storage access and dual Blue sea elec panel to replace the ashtray.

mounting is pretty straight forward - 3 screws and 2 bolts on the lower - I found I had to remove hangers for the rear taillight wire runs.....

bolted in it's pretty rigid.....and with the woofer in place will be more so - I'm still thinking I'm going to run a angle iron channel up under the 2 left mounting points and catch it onto one of the woofer mounts to esnure it stays firm....

after mocking it up my thought is that I will mount the woofer by cutting out the right shape into the panel and using a 3/4 or 1 " spacer to match it up........ unfortunately that will mean cutting into the "vent" below the factory grill so likely I will end up getting the whole panel covered in vinyl and Glassing / fatt mattting the inside to make it as much of a "cabinet " as I can....

I've ordered up a Rockford Fostgate 10" that will run free-air and matching grille / and the two options for spacers - hoping to finish it off early this week.......

Anyone found other options ?

 

[RS6tofj80]

The sub and spacer arrived today.... ended up going Kicker as the RF was backordered and supposedly not as good for Freeair - or modified Free air as I hope to do....

Might try it out tonight and post up some pics. Anyone else got their bracket and sub in ? thoughts or comments and what worked or things to do ?

thanks

 

[AATLAS1X]

Happy Memorial Day to all.

We have our yearly Memorial Day sale till the end of the month, please see my sig line.

I have the last of this run up for sale till the end of the month, here. http://shop.metrictlc.com/80-Series-10-sub-woofer-mount-G-30.htm?categoryId=-1

 

[AATLAS1X]

I made a few pretty good mistakes the last few months on the sub mount and the accessory mount that mounts behind the cubby in front of the sub mount. I didn't call out the material thickness on the mount and I did on another part. So they assumed they were the same thickness. The first run of sub mounts were done in 18ga and were so flimsy.

The accessory mount mount I failed to mate the two together in SW and forgot they shared the same hole. They do not! So you couldn't mount them together.

One pallet of ACC mounts went to the recycling. I was sideways about my mistake, however I fixed it and improved on the design. Should have those in a few weeks. Pictured is a drawing showing them together and I maxed out the space. The extra hole in the bottom is for the OE wiring harness clip.

 

[BigAxeJack]

I finally completed this install! I ended up going with a smaller amp that fits in the original cubby space. Eventually I'd like to get the accessory panel and mount an inverter, etc in that spot, but I'm happy for now. It took some cutting to fit the MDF spacing ring behind the trim panel. Also the ring pushes the panel out just enough to cause one top trim clip to not engage fully.

This had been a trouble spot in my cruiser since I purchased it. The PO had gone to great lengths to have a 6" sub installed in a custom box in the factory sub location. The "professionals" had used plumber's strap and wood screws to hang the amp in the dead space, and this had it such that the cubby and door could not be used. Then the PO managed to lose the factory speaker grill. So my quarter panel has been full of holes since day one. Not any more!

When I first installed the bracket and turned it on the sub sounded crappy. Lots of rattles and the "comb filter" effect mentioned earlier. Taking out the third row seatbelt assembly helped with the rattle. Once the sub and trim panel were tightened down all the rattles went away. I still get some combing at high volume, which I attribute to the vent-like opening directly below the cone and the fact that this is a less-than-acoustically-ideal set up. Maybe I'll seal that vent up later, and maybe it'll help, but I'm still pretty pleased overall. This bracket option probably won't impress the low-rider crowd, but to have both storage and bass in the Cruiser is pretty sweet! Thanks AATLAS1X for giving us another option!

I'm curious how some of the others' experiences with this sub mount have been...