[mauiliner]

I'm just about to instal my new JBL component speakers (GTO 608C) in the front doors and wondered if I should use the Scosche SAHR6 Speaker Mounting Brackets or a spacer ring like Heli did in this thread http://www.ridgelineownersclub.com/...ics/43960-jbl-gt6-6-6-3-4-2-way-speakers.html

Also, what is the deal with the F.A.S.T. system?

 

[optimus29]

I would go with 3/4 MDF rings, The fast rings I believe i have 3 pieces that are used, not sure but I do no from reading the article on them, blocks out unwanted noise's

 

[OhSix]

I'm just about to instal my new JBL component speakers (GTO 608C) in the front doors and wondered if I should use the Scosche SAHR6 Speaker Mounting Brackets or a spacer ring like Heli did in this thread http://www.ridgelineownersclub.com/...ics/43960-jbl-gt6-6-6-3-4-2-way-speakers.html

Also, what is the deal with the F.A.S.T. system?

Aside from being a spacer to align the face of the speaker with the opening in the door panel, the function of an adapter is providing a mechanical coupling between the speaker and inner door sheet metal, improving the interface of two baffles the speaker will vibrate. In that regard, MDF is more "robust" than molded ABS. The degree to which acoustics benefit from one or the other material is not only subjective, but dependent on other factors such as power fed to the speaker. In a high power system, the more attention paid to coupling the speaker to the inner sheet metal, the better. IMO: the "improvement" offered by the increased density of MDF over ABS is incremental in most applications but is never wasted effort.

Be aware: since the door is somewhat "leaky" (environmentally speaking) anything inside the door will be exposed to more moisture than it would if it were used inside the cabin - sometimes coming into direct contact with water. Since MDF is glue and saw dust, it does not handle moisture well and will decompose overtime.

If you purchase or cut your own MDF plates, its a good idea to spend a little time coating them with spray rubber or moisture resistant primer/paint like Krylon.

Currently, I'm using a combo of 1/2" MDF coated with Eastwood spray rubber. The plates are laminated to 1/4" ABS. The stack up turned out to be perfect, with the door port meeting speaker face perfectly.

A few images for your review:

 

[mauiliner]

Great info OhSix!
What is the reason for stacking MDF and ABS? Can I just use a 3/4" MDF ring (sealed of course)?
Aloha!

 

[OhSix]

Great info OhSix!
What is the reason for stacking MDF and ABS? Can I just use a 3/4" MDF ring (sealed of course)?
Aloha!

MDF & ABS = superior acoustics via resonant management accomplished by isolating the materials thru use of micro-thin double-sided thermo inductive polymer tape! PFFFT!

Seriously, the real reason was: there happened to be scrap 1/2" MDF & 1/4" ABS laying around in the garage. Plus I was itching to experiment - and get those monster Silver Flutes installed. Which really means I was too lazy to make a run to the hardware store. LOL.

The stack up worked out by shear dumb luck. Errr, I mean a detailed study of door curvatures and precise measurements.



A`ole pilikia!

 

[Elkhunter]

I'm just about to instal my new JBL component speakers (GTO 608C) in the front doors and wondered if I should use the Scosche SAHR6 Speaker Mounting Brackets or a spacer ring like Heli did in this thread http://www.ridgelineownersclub.com/...ics/43960-jbl-gt6-6-6-3-4-2-way-speakers.html

Also, what is the deal with the F.A.S.T. system?

I went with the carpet lined MDF spacer rings with my JBL GT7-6's....just with I had thought to paint them as OhSix suggested.