Very nice review. This makes me really wanna go out to my truck and start fooling around with the tuning a bit. I believe currently my crossovers are setup at the same points you had initially, so I wanna try bumping up the tweeters and rolling the mids off a little smoother like you did.
It's worth a shot. When I originally tuned the system, I played with a variety of crossover points and kept notes on each one. Going back for a retune, I reviewed the notes and started working with alternate permutations, eventually arriving at the present config.
I also find that walking away from tuning helps. I know from experience that my ears lose their acuity after ~1/2 hour of concentrated listening. If I'm tuning, say, the EQ, and I make more than 2-3 changes in that time period, I shut off the system and come back later.
If you don't mind what does the gear in the install entail and could you give a general description of the install? Looks like you mentioned a 9887 HU, are the doors deadened and sealed, were the mids installed in the doors or in kicks and such.
HU - Alpine 9887
Tweeter amp - ARC Mini (to be replaced with a Zapco 200.2 later this week)
Mid amp- Zapco AG350
Sub - Blaupunkt PCwb1200 in 1.5ft3 ported (this thing is sensitive enough to drive with a hair dryer)
Sub amp - PG Xenon X400.1
Car - Evo IX SE
The mids are mounted in the factory locations low in the doors. The doors are deadened and sealed with RAAMmat. Due to the Polks' prodigious low-end dynamics, I still need to address an audible vibration in the door cards that manifests itself at ~80Hz.
The tweeters are installed low in the A-pillars. As the tweeters' frequency response noticeably varies with positioning, I tried to aim them symmetrically. Meaning, both are off-axis to the listener.
Due to the nature of the car, weight was and still is a major consideration: the sub and its enclosure weigh a total of 33lbs, the amp racks are made from Baltic Birch to save weight...well...you get the picture.
The tweeters definitely do like to be mostly on axis, I believe within 15-20° they seem to loose a bit of detail in the upper region when placed off axis, still sound wonderful with the relatively lower frequencies but a hint of just something missing. Least this is what I found when experimenting with them.
I found that having the tweeters on/off axis was mostly a matter of amplitude. The musical information remained; it was just projected at a lower relative volume. This said, I usually aim high-rez (home) speakers directly at the listener's ears and gain a greater sense of focus.
Thanks again, definitely a big fan of the SR6500's specially active
Any time. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif
