Originally Posted by frozenice
Hey Lock, to make your system work which includes Dynamat, separates and an amp you are about 5X over budget and that is if the OP has the time, equipment, skill and desire to do plenty of DIY work. My ideas work, can be done easily and on budget. If you don't use Dynamat and separates on your system you have serious issues with bass, sound leakage, door vibrating and sound imaging.
And by using rear speakers as fill are you going back to the fifties when there was just the mono radio speaker in the middle of the dash ?
Read my subsequent post. I missed the part on the $50 budget, my mistake I apologise. If I had noticed, then the posts from other members such as yourself make more sense. Again, I apologise.
However, I'm not thinking of the 50s. I was thinking of the Hundereds of SPL and SQ competitions and numerous articals in Car audio magazines. I'm also talking about the analysis of the Bass 'Q' and the fact that the rear speakers can actually interfere with a clear sound for the driver.
I have an Audi TT, it uses the rear speakers powered off a separate amp (all factory fit not modded) as a 'fill' speaker. It also has a small sub as it is the 'Bose' set up.
This is about as good as you will get in in a car from factory (there are some expensive exception) and to my ears it is not good enough.
Rear door speakers are a waste of time really as the sound is directed away from you. all you get is reflected sound that due to the lack of timing correction inteferes with the front speakers which are building the sound stage and doing most of the work.
If you have a sub, and a decent set up, you can adjust the bass Queue to avoid this timing issue for the bass at least, and the fact that the low frequency bass is not really directional there is no problem.
If you have parcel shelf speakers, as the sound bounces (in most cars) straight off the rear screen and toward your head you can adjust for this timing issue a little more, but it will still muddy the clean stereo you will get from the front speakers. The other problem is that although door speakers can use the door as an 'enclosure' of sorts, the rear parcel shelf speakers are essentially 'free air' speakers. They will never give tight bass response and are prone to bad resonance at high volume. You will also need to build a solid parcel shelf to have any chance of good sound and these are extremely unsafe in most cars.
Rear speakers in the right application can sound ok but you would have to put so much effort into it, and get no real benefit over a decent set of fronts... why bother.
If you are only spending $50 a pair then go ahead. It will sound pretty awful anyway, but I would say the money is better spent on some front components. That is my opinion.
Someone posted the idea of kick panels. This is a great idea. If the front speakers need to be in the door. Kick panels or 'Pods' can make a huge improvement... can be very pricey to get right though.