Where are the resident automotive audiophiles?

So at some point in the future, I am going to put a more modern stereo in my '68.

I am definitely going to replace the factory speaker in the dash with a newer dual speaker setup.

I want to put another set of speakers up front, but I don't know where. I am definitely not cutting holes in my doors. It doesn't look good and it always looks like an afterthought. I've done it several times for other Corvair owners and I hate it. Also, the kick panels are out since they are also the fresh air vents.

So I think I'm going to make some custom brackets to mount some 5.25" speakers under the dash facing down towards the floor or slightly angled towards the passengers. Anyone have a better suggestion?

I am also going to need to build a speaker box to fit in the parcel tray behind the backseat of my '68.

I'm probably going to do a 5.25" speaker on each side of a 10" sub, with an amp mounted on the front that will be hidden by the back seat when it's in the up position.

So what materials are suggested for building a speaker box?

I squeezed a pair of 5-1/4" in the original single-center-of-dash mount on my '77 Silverado. Doesn't sound wicked-awesome, but it works just fine to overcome the wind and rattle noises in the truck. I used a plastic cutting board to fit them.

The problem with having speakers in the front that fire downwards into the carpet is that you don't get particularly good sound that way. IMHO you should at least try to get components and move the tweeters somewhere else.

I'd also not put speakers into the center speaker mount if you want half decent imaging. In fact for a half decent audiophile system, you want as few speakers as possible so you don't have to fill the trunk/frunk with processors to make the whole shebang sound properly. Unfortunately the obivious place to put the speakers is the place you already rules out (doors). I can understand that, I have a strong dislike for doorcards with big holes sawed into them myself.

Is there a way you can fab up a small enclosure that you can mount to the door cards using existing screws? Say, something to replace a door pocket or similar? If that is a possibility I'd consider putting midbass & tweeters into the door-mounted enclosures and put a small sub in a very small enclosure into the center speaker mount. With the right frequency cut-off this could work. Or it could make your dash jump out the car...

Damn. I was hoping for this:

BTW, SBF, could you post up some photos of the door, front footwell area and maybe the dash to give us a better idea what you're working with?

In reply to BoxheadTim:

Yeah I'll grab some tomorrow

Could you fabricate your own kick panels with speakers in them?

In reply to SkinnyG:

It's hard to do that. The fresh air vents are a valuable thing to have especially in a coupe. There isn't a whole lot of room for modification.

Here's what I've seen done:
Enclosure built and mounted to the center tunnel in front of the shifter. Speakers pointing toward the doors or the occupants (I've seen these enclosures in different cars and Jeeps). I've also seen 8" or 10" subs built into a small box that became the passenger toe-kick (the transition between front floor board and firewall) and the interior carpet went right over it. I saw this done in a 308 and it was amazing! How about an enclosure that goes where your kick panels go, but with a duct to allow the air to still flow?

Going to need pictures to give a better suggestion. Tim has the best suggestion so far with using components. I'm a firm believer in them.

Maybe build an enclosure in between the footwells that have speakers facing up?

Edit: Dr. Boost beat me to it while I was looking up Corvair interior pictures. I am redundant

Alright, so here's some footwell/under dash pics

I think I'd fabricate a center console.

Put a box in front of the shifter.

I've installed speakers under the dash facing down when there was no other choice. It wasn't perfect, but it worked. I would use a woofer under the dash, with a pod tweeter mounted up on the dash, door or pillar for the best results. Stuff some insulation around the back of the speaker for better sound and bass. Fiberglass works, as does the sound deadening (mixed wool looking) material you can find in car trunks. You can tone down the tweeter with an inline resistor. For the rear, since nobody else answered, use MDF for the box. 3/4" is best, but 1/2" will do if you add some internal braces and it's not too big. Skip 5 1/4"s for the rear if you can and go with 6 1/2's for the best results. A pod tweeter in the back might be worthwhile too. You can mount them with self adhesive velcro and there's no mounting holes or damage.

On my Trans Am, there was a late production option in 1979-80 that had two 3.5" speakers mounted where the 4x10 mono speaker would usually be. I lucked out and found a Camaro with the same option at a junkyard years ago, but when I misplaced it, I used the factory speaker bracket for the 4x10 and mounted them in there. It doesn't sound the best, but at least there is music coming from up there. It should be super easy to fab up a mounting bracket if you go that route.

My car had 6x9's in the rear from the factory if it was optioned that way, but mine wasn't. Someone surface mounted a pair in my package tray years ago, so I just replaced them with nice Boston Acoustics ones. I can't hear the stereo over the Flowmasters anyway, so whatever.

When I strip the car down for it's upcoming resto, I am going to have to replace most of the interior. When I do that, I will get the factory-style 6x9 package tray, and it's getting some sound insulating mat of some sort. And quieter mufflers. These ones hurt.

In my 64 im building custom enclosure for the kick vents. Sliders for airflow actuated by a choke cable, and a baffled "pod" tomount my 6.5 iinfinity reference in. Also running a pair of tweets in the upper front corner of the door panel to raise the soundstage Rear speakers will only be for fill, if necessary at all. A 10 inch, with a 3 channel amp will be rounding out the audio package.

Pivk your head unit first, locations and size of front drivers second, build the rest to fill in the holes.

I shouldn't have come back to this thread. I'm going on eBay looking at Corvairs now. If I buy one, I'm telling my wife to IM SBF and direct her wrath that-a-way.

SyntheticBlinkerFluid wrote: So I think I'm going to make some custom brackets to mount some 5.25" speakers under the dash facing down towards the floor or slightly angled towards the passengers. Anyone have a better suggestion?

Accurate sound in the mid and treble range requires a soundstage that comes from primarily a direct source.... meaning that the speakers point toward the ears, or at least have a direct line-of-sight to the ears. If you are looking for quality sound, this would be a very poor location. The reason is, higher frequencies don't make turns well. Its why when a boom-boom car drives by you only hear the boom and not the treble. The long sound waves of bass go through things. High frequencies are easily quelled when they encounter something. If your speakers are aimed at (for instance) the floor mats or someone's shoes, the frequencies that are absorbed versus the ones reflected are highly variable and you get a poor soundstage.

For the same reason, the best location for tweeters is in the same place, or within about 3-4" of the mids. If they are placed further apart than that, your ear can distinguish between their locations. You might end up getting the same frequency production, but it will sound like there are little speakers screaming at you. Keep them close to the mids so the sound waves play well with each other.

The only way I would choose this is if you are desperate for tunes in the car and don't want to hear anything with clarity. If you are looking for quality sound, this is the absolute last place I would put speakers.... well, except in the engine compartment or something.

Best position for mid drivers is always at a point that is equidistant from each ear and as close to eye level as possible. In a car that is nearly impossible. Doors are mildly acceptable as long as there is a console or something in the middle. Speakers that point directly toward each other make odd standing waves, and a small movement of your head left or right can make big "pockets" of frequency cancellation. Dashboards at or near the corners is ok, but the driver's side will be much closer to the left ear than the passenger side will be to the right ear. That is why kick panels are almost always the best choice.

I am also going to need to build a speaker box to fit in the parcel tray behind the backseat of my '68. I'm probably going to do a 5.25" speaker on each side of a 10" sub, with an amp mounted on the front that will be hidden by the back seat when it's in the up position. So what materials are suggested for building a speaker box?

MDF is the material of choice. 3/4" thickness should be fine for all but larger panels. When you screw it together, always use some form of adhesive, always pre-drill, and use longer screws than you think you need. I use 2-1/4" or 2-5/8" in 3/4" MDF. The reason is, MDF is basically like cardboard that is glued together under high pressure. Screwing into the end grain is a terrible way of holding it. For that reason, I use a polyurethane glue or epoxy (oh, alright, sometimes I use elmers) and assemble it with long screws. Don't use the screws as your mechanical bond, they'll loosen and eventually fail. Basically think of the screws as permanent reinforcing clamps that stabilize a glued joint.

In reply to curtis73:

Thanks for the info. I think the front speakers are going to be trial and error.

DrBoost wrote: I shouldn't have come back to this thread. I'm going on eBay looking at Corvairs now. If I buy one, I'm telling my wife to IM SBF and direct her wrath that-a-way.

Hey now......

http://youtu.be/rbMo1Tp6GnE

SyntheticBlinkerFluid wrote: In reply to curtis73: Thanks for the info. I think the front speakers are going to be trial and error.

Sounds like my first wife... ba dum dum, tssss

I thought about suggesting separate tweeters so you could hide the 5.25s under the dash and have tweeters pointing out, but that would really sound "screamy."

Its hard to tell from the photos, but would it be possible to hang speakers down from the lower dash pointing back toward you? Let me draw something quick to demonstrate...

curtis73 wrote: I thought about suggesting separate tweeters so you could hide the 5.25s under the dash and have tweeters pointing out, but that would really sound "screamy."

Not if you do it right

If you built some little wedge boxes like this:

So that you could mount the speakers facing like this:

They would be removable, point in the right direction, and sound better. You could shape them and contour them by using foam molds and fiberglass, or even better... what about a 3" long piece of 4" PVC pipe holding a toilet flange? Mount the speakers to the flange, screw it under the dash so it points out? Totally removable. No cutting doors.

Go onto Youtube, look up a guy named Steve Meade, and in his videos look up the worst shop build ever.

He basically goes back and fixes a terrible job by another shop on a classic. its like 10 parts video, and may give you good ideas.

I'm not sure if I remember this 100% correct, but I recall hearing that anything around human voice frequencies is mostly handled by the tweeter. Anything below can be handled by a good quality bass unit - not a sub-woofer per se, but a quality speaker that's light enough to still handle frequencies that are not totally bass frequencies. Careful enclosure design will allow good bass reproduction from the same unit.

Is it possible to mount a dome tweeter (best for sound dispersion according to this website) somewhere in a convenient hole in the top of the dash? Then maybe you can do away with the need for a large speaker in the front, and just have them in the rear of the cabin.