some car audio decisions

[J_Dunavin]

It is just a work car, but i've got some decent gear that i'm not using, so i might as well put it to good use.
So far:
Keenwood dkc X589 cd player
Kac-x4r amp
Boston 6.2 component front speakers
kfc-x130 5 1/4 rear speakers
Audioquest speaker wire
"peal and seal" sound deadener... works pretty good!

SO..
I want to do something a little more special than just wood screw this thing to the seat back.
Right now i am leaning toward making a false floor with a plexi window to mount the amp under. Buy some cheap used amp thing, to run am autotuba. (Don't worry the x4r can handle all my crossover needs. )
BUT if i do an auto tuba then it will sit over my cool plexi window deal.
Iv'e also thought about two 8 inch JL w1's. That could also sit under this, now taller false floor.

So i guess it comes down to an auto tube vs. two eight in JL's, and cool looks, vs. overall functionality.
The auto tuba is still unique enough. I guess I could install the amp on top of the auto tuba with a trim panel over all of that, but then the auto tuba doesn't come out, if i need to..... though i suppose after it's all said and done, two JL's would take up the same room.

Oh i should mention that I don't have the JL's or a driver for an auto tuba, but that the guy i bought the boston's from has the JLs He made me a fine offer.
I also don't have an sub amp yet... any takers????

[Steve Regier]

Are you going to listen with your eyes or ears? ... seriously. What is more cool a plexi floor and showy gear that may boom but ,eah it's like every body else. Or do you want a sub with serious fidelity and efficiency that those JBLs can't touch all powered on a $50 amp from Walmart. I find that EVERYONE that has been present for my Autotuba demonstration is impressed that a single 8" sub powered on a tiny amp can be so refined and powerful. On the other hand I just installed dual 12s in a Focus. They are boomier but muddy and very much like everything else out there... but if that is what you want.....
I vote for the Autotuba.
If you really want to get strange get a tube amp kit and run the tuba on that. Now that would be dinner and a show.

[CoronaOperator]

My advice and for what its worth, I'm still working on my car system 22 years later, getting real close to being finished


If you plan on showing your car or competing then go the fancy route, if not I wouldn't bother making the trunk all fancy. PIA for everyday life like road trips, shopping, changing flat tire etc. I'd spend my time and money where it counts, on the sound. The autotuba will absolutely destroy 2 8" jl's, heck it will destroy 2 12" jl's. If you don't have your amps bolted to it, it can be removed when nessesary, be it a house party or for a flat tire.

With what you got I'd recommend you use your sound deadener for the front doors (30% coverage on the flat panels is plenty), 6.5" woofer in the front doors, might have to make a baffle for it depending on the car. Seal up the baffle and any holes you can in the door with plexi, caulking, screws, or all of the above. if you use a mdf mounting ring, seal it to prevent water damage. If you can't use the factory mounts, use one of these http://www.parts-express.com/pe/showdet ... er=260-788 to prevent water damage to the woofer, just cut out the bottom half so the woofer can breathe. Think umbrella.

I'd mount the tweets in the a-pillars, might want to experiment with double sided tape for a while until you find a sweet spot, every car is different.

I'd also ditch the rear speakers unless you want to get into 5.1 or 7.1 surround sound. Rear speakers will only drag your image behind you. In a car imaging is everything. You want the sound to be at the center of the dash at eye level.

I'd also go with the autotuba. It sounds phenominal and will go louder than your front components can keep up with, it also has a cool factor. When I tell the pro audio sound companies around here that I have a folded horn in my car, they go nuts and insist on an audition, they leave the audition with an ear to ear grin on their face and let me in on their secret audio club!

After that I'd bridge your amp for your front components and purchase an amp for the autotuba. Something along the lines of a hifonics amp, cheap, loads of features, and gets the job done. Wire your amps up with the proper fuses in place (by the battery) to protect your car.

Then its just a matter of tuning your system. Your amplifier has some dsp features like time alignment to get your image right and your cd player has some eq available. If your lazy like me a jbl ms-8, or jbl ms-2 might be up your alley although I do have a DCX2496 in there for good measure

Have fun with your build!

[CoronaOperator]

If you really want to get strange get a tube amp kit and run the tuba on that. Now that would be dinner and a show.

Done that with a Butler TD1500. It didn't have the punch that a solid state amp has, maybey a bad design? I'm using a sony explode (not recommended - overheats) amp now and using the tube amp for the mids.

Added some pics, I learned that around here without them it didn't happen


nice orange glowing tubes

http://s769.photobucket.com/albums/xx33 ... ?start=all

[Tom Smit]

AT

[J_Dunavin]

What's the recommended voltage limit? High pass freq? ect?

[Mikey]

The recommended MCM and TB drivers are 4 ohms, but 4 0hms is also added by the horn, so total cab impedance is 8 ohms. If you use dual drivers, wired in parallel, cab impedence is 4 ohms, which is much more car-amp-friendly. A standard single-driver AT is 15"w, but a dually is only 3" wider ... 18".

HP @ 40hz.

IF memory serves me correctly, you limit at 22v for the MCM 8"er. With drivers in parallel, that doesn't change.

[J_Dunavin]

22v? So maybe i should be looking for an amp that's rated somewhere in the 150-200W @4 ohm range?
That should give me some head room too right?
I may bid on an Ebay amp soon... is a 100 W enough?

[Tom Smit]

22 volts it is. And an amp that does 100 to 150 watts at 4 ohm is right. But just make sure you hook up a volt meter to it while running the AT to get a feel for when you're at the limit.

My door speakers aren't great so I low-pass at 140 hz.

[Kirk Baptista]

As for the convenince factor of being easily removable, for my AutoTuba I wired an RCA jack in the wall in the back compartment, along with a cig lighter port. My amp is installed on the closed end of my AT, and I extended the AT sides to surround and protect it. Last, I cut handle holes in both ends and wired the amp up with a short RCA for signal and a cig lighter adapter for power. When I want to remove it, I just unhook two things and it's out (or back in). Now the only problem I am having is it sliding around, so some rubber feet may be in order.
.

[CoronaOperator]

... with a short RCA for signal and a cig lighter adapter for power. When I want to remove it, I just unhook two things and it's out (or back in) ...

How do you manage the remote amp turn on wire? I see dead batteries if you forget to unplug the amp, or is the powerwire drawn from the ignition switch? The OP would be hooking up 2 amps, way to much current for that. They do make 70amp relays which could handle the current.

[Kirk Baptista]

... with a short RCA for signal and a cig lighter adapter for power. When I want to remove it, I just unhook two things and it's out (or back in) ...

How do you manage the remote amp turn on wire? I see dead batteries if you forget to unplug the amp, or is the powerwire drawn from the ignition switch? The OP would be hooking up 2 amps, way to much current for that. They do make 70amp relays which could handle the current.

The power outlet is switched by the ignition. The remote power is jumpered from the main power.
Small amp, seems to work fine.