Supraloud84 said:
4x6's will fit nicely. In my opinon I would recommend installing a really good front stage setup first. mabye a 6 1/2" compnent set, building door or floor pos and mount the tweets at the base of the A pillars. You wont even feel the need for rear speakers and it will sound a ton better than just putting rear speakers in. It works on the theory of imaging and staging.
I agree. I've had two Supras with two different sound systems. My first had 3.5's in the front, 5.25's in the back and a 8" sub. It sounded pretty good but I could hear the loss in the mid-range. The bass was great though. In the other setup I have 4" in the front and 5.25" in the back with no sub. The mid-range is a lot better and if I ever add a sub to this I'm sure it will sound a whole lot better, but I still feel it will lack in the mid-range. I think if you're gonna get serious about audio in an mk2 you really do need to go with seperates in the front. A 6.5" woofer in the door panel, a 3.5" in the stock front speaker location and a tweater hanging off the A pillar or flush mounted right on the dash where it meets the A pillar (that last option is a lot of work, but would look and sound great).
As for the rears... Well, the 5.25" is probably the best you can do in terms of sound quality. I've heard that the oval shaped speakers have a muddy bass sound and are not recommended if sound quality is important. The important thing about installing a 5.25" speaker is to create some kind of baffle by creating a barrier around the speaker frame to keep the air from the top side of the driver from mixing with the air from the bottom side. In other words, you want to prevent the +ve sound waves from cancelling out with the -ve sound waves (this is what makes an open-air speaker sound very tinny without any bass at all). What I did was use some simple putty and gause and just sealed off the open spaces around the stock frame so that when I fitted the 5.25" speaker into it there were no gaps around the frame itself. I then took some pillow filler ($3 for a bag at WallMart) and stuffed the inside of the panels to limit the size of the baffles (the panel cavety where the speakers are located is a huge air pocket extending from the back of the car all the way to the doors and is anything but air-tight) . By doing this you also help prevent panel rattle as the pillow-filler presses against the plastic panels and holds them firm (I highly recommend pillow-filler even if you don't care about sound quality just for this reason alone). It also acts as a mild sound deadener. And oh yeah, I also installed real sound deadening material (Brown Bread, sorta like Dynamat) on the speaker frames to prevent any rattles caused by the speakers. I placed Brown Bread all over the car's sheet metal over the wheel wells to lower road noise and to help further reduce any vibrations caused by deep bass. All this adds up to a much quieter car with better sounding speakers. The same can be done in the front.
Hope this all makes sense, I realise I'm babbling here, but I figured someone might find it all useful.
- Mike