Over the years I built out my system using only high quality components. I have JL Audio XRCSI 6.5 fronts and a JL 10w6v2 sub in the rear. I have an Alpine head unit that I am replacing with a pioneer premier because my crossover is going out. The system was designed on paper and installed by a true pro….The simple truth is I cant STAND how it sounds…It isnt the speakers I don’t like it’s the gap I have from the sound of the front speakers to the sound of the sub in the rear. .I cant correct it I’ve tried. In the end I think I just don’t like sound staging from the front only. Call me a noob or whatever but every car system that I have heard that I truly loved had LOTS of speakers and LOTS of power. So now enters the question..I no longer care who laughs or who says it sounds like crap I want REAR FILL…I thought about adding a couple of 8 inch mid bass but I feel like that is to close to the sub. So should I add 6x9 ( I know everyone dreads them) or should I add 5x7s or just some 6.5s….I know one thing for sure my days of being an audio snob because it was the "right" thing to do are over...
It seems that you are experiencing a severe loss in the critical bass-to-sub freq range. Adding speakers won't fill this gap. Your description "it’s the gap I have from the sound of the front speakers to the sound of the sub in the rear." tells the story.
Adding rears for fill may help with front soundstage imaging if done just right, but shouldn't be considered to fill in the missing music range. They may help raise the front soundstage in some applications, but if woofers are added behind you that provide the (~)60 to 100 Hz range then the problem will still occur. It would be akin to raising the LP filter on the sub to a higher frequency. That is to say, it's still behind you and the front soundstage is supposed to be designed to sound like its in front of you.
You should redesign the front and add the necessary ingredients so that you feel an impactful punch in the 80 Hz region. Like a sharp rhythmic drumbeat. It is those front woofers that should make you feel it in your chest.
Some of the things that might be wrong with your system: inadequate damping of the door sheet metal panels; loss of waves from front to back of the woofers (bad seals); flimsy mounting (no solid mounting baffles); the use of pods instead of door locations; poor crossover setup; faulty crossovers or other gear; et cetera...
As you know, this is only my opinion based on your posted information. But I believe that you should get the system (using the fronts only) properly blended with the rear sub before adding additional speakers to the problem. Make a test CD of tones in a multitude of stepping frequencies that will adequately cover the problem area. Also, record some sweeps that cover that range. This will give you some more solid data to work with.
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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.
The way I usually fix my staging with rear speakers is by eliminating them. This has worked every time I've tried it so far.
Read the post again. He has no rear speakers besides the subwoofer. He is thinking about adding some full range speakers.
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Well I went back to the basics...I cut off the EQ, I cut off the sub, leveled all of my treble/bass levels to 0 and changed my crossover for my components back to reference settings...What I figured out is my highs and mids sound like crap. They are muffled and dont produce enough sound. At this point I dont know if it is the speakers or the head unit sound I dont like. I need to pull new wire and play with the tweater positions. The 6.5 and tweets are installed low in the door. The 6.5 is mounted in an MDF ring in the door and the tweet is installed just behind it. I wanted the tweet installed just above the 6.5 but I cant because the window crank. I can build new door panels...So now the delima is what to do....I dont moving the tweet around is going to "liven" up the system...In the end I may be jaded as these speakers are crossed over and I might not like the sound because they arent full range..I really wish I could get this worked out because its driving me nuts...The one comment that has confused me so far is the Alpine comment. I have seen plenty of competition systems with Pioneer decks in them. In my opinion the premier line isnt a bad line of head units. I got into car audio a long time ago so I know there is a nostalgic old school pull for some people. The old amps were better in my opinion but I dont think HU and speakers have done anything but get better..So why do you feel the older Alpine mid-gradeHU is better than a new top of the line Pioneer primier...