Stereo. amps. & sub questions

[rauto13]

I just got a 12" sub installed behind the seat, sounds good, I think I have already pissed off the neighbors. I have a couple questions though.

The rear panel of the truck now vibrates badly whenever the sub hits. Will Dynamat or something similar stop this vibration? It is pretty annoying and the vibration sounds really bad outside the truck.

I put in a Jensen amp that I had laying around. The amp is 2/3/4 channel. I have put the amp in three channel mode and bridged the outputs to one four ohm sub and did not hook up anything to the other two channels. Will this hurt the amp running bridged into one sub, with nothing on the front channels on the amp?

I looked up the instruction manual online and the amp is meant to be bridged and can run four seperate channels, two channels with the rear channels bridged (three channels), or front & rear channels bridged into two speakers (two channels). I am thinking it is okay to run just one channel off the rear bridged outputs, but don't want to burn it up.

Does anyone know how well a passive radiator setup with one 12" sub works? I need as much room behind the drivers seat as possible, hence only one sub behind the passenger seat. I thought about using the Blaupunkt overdrive subs and cutting my box down, but they are not available any more. Too bad, only three inches deep mounting depth.

Anyone else know of any very thin mount 12" subs, say 4 inches mount depth or less?

Thanks for the help.

ps. Anyone got a couple of 12" Blaupunkt overdrives ya don't need anymore?

[randomhero472]

any free air/radiator sub isnt going to have the sound of an enclosed box, i would think you could find a sub w/a shallow depth, check www.crutchfield.com, another way to do it, if you know what your doing is to line the rear wheel of the cab and then build a fiberglass/wood encloser off of it, that would easily give you 3/4"-1.5" more depth for mounting the speaker, the amp should be ok the way you have it wired up.. and dynamat will solve 99% of your rattling problems, hope that helps

[rauto13]

I have a sealed box behind the seat for two twelves, only have one installed and playing, cause the one behind the drivers seat makes the seat too far forward.

I have seen a passive radiator at Crutchfield and am thinking about using it in the sealed box with the other 12" sub, the shallowest sub I have found is about the same as I have now. I was thinking about trimming the drivers side of the box and putting in the passive radiator, due to the shallow depth of the passive radiator, anyone tried this before?

I don't have the skills to custom make a box with fiberglass

[djracer]

I would not use a passive radiator! You should hook your highes to the other 2 channels of the amp it may damage the amp not having a load on those two channels! Give me the max dimensions you have for a box and I'll see what I can find in a shallow sub!

Kevin

[rauto13]

I actually think I can use the one sub that I have already in, the bass is definately enough, but I have one side of the box just sittin open, thought I would try the pass rad just to fill the hole, looks kinda weird with an open hole for a sub.

I'll measure it tomarrow, I want to cut the box down so that I can put the seats back as far as I can, I thing about a 4 to 4 1/2 inch mount depth I could live with, maybe, just maybe 5 inch depth

Although after driving the truck around tonight, I may not use another sub, I am thinking about just cutting down the box and having a place to mount relays, alarm, wiring, etc...

I'll get pics tomarrow and post them for some ideas

little tired right now

and DJ, just curious, why not use a pass rad?

[tbirdman88]

http://www.earthquakesound.com/SWS04.htm look at this web sight, i just heard about these yesterday. as thin as 3" mounting depth. there is guy here in wichita ks area that can get them. hope this helps.

donnie-87 short1/2 ton crewcab
tbirdman88

[djracer]

Rauto
Passive radiators kinda died in car stereo in the late 80's! They are subs now that work in really small enclosures and still sound real good! I put 2 twelves behind the seat in a new 2500hd crew cab and its really tight! One thing I would suggest is to build your box out of 1/2 MDF! That would help your depth problem!

Kevin

[randomhero472]

another option if you plan on keeping one sub is to build yourself a box that would be ported for one sub, and shallow for behind your seat, i've done tons of these boxes when i worked for a jl audio/alpine shop.. pm if you want, i could draw you somthing up that would work and actually be quite a bit louder

[djracer]

Originally Posted by randomhero472

another option if you plan on keeping one sub is to build yourself a box that would be ported for one sub, and shallow for behind your seat, i've done tons of these boxes when i worked for a jl audio/alpine shop.. pm if you want, i could draw you somthing up that would work and actually be quite a bit louder

If output is all you are looking for this would be a good option! I personally prefer the sound of a sealed box! In my 95 suburban I had a huge ported box with 4 15's with 2000 watts on each and it was unreal! We had it tuned real low and if would shake you teeth out!

Kevin