For those of you with an Alpine unit that has this feature....do you use it, and what are your thoughts on it?

I'm in the process of setting mine up now....I'll let you know what I think later.

 

WOW....what a difference in sound quality! I can't believe how much better this made everything sound (I'm still running factory speakers). It definitely shifts the sounds stage to right smack dab in your face. Everything is much richer and full and right there in front of you. I even have the fader set to -3 and it still feels (sounds) like the Dave Matthews Band is playing on my dash. If you have an Alpine that has this feature and you haven't set it up yet....GO DO IT! It takes a few minutes to get all the calculations an do the math, but it's well worth it. I can't believe how much better it made things sound.....it's gonna be awesome once I get my Infinity Kappa's put in.

 

What numbers do you use for your time corrections?

 

I guess they would be pretty much the same for most of us, huh?

Anyway.....

FL = .8
FR = 0
RL = 3.1
RR = 1.8

Hook your's up and let me know what you think?

 

Those calculations seem kinda weird because usually the closest speaker next to you should have the longer delay which should be your FR, your RL which should have the least delay because your back seat is blocking the soundwaves. These wont match up very well if you have a sub in the back because the bass won't hit excatly on the beats it should be.

 

The FR (Front Right) is the farthest speaker from me, therefore its value is zero. The FL (Front Left) believe it or not is almost the same distance away as the FR speaker....therfore its delay is the least. The RL (Rear Left) is definitely the closest to my head, creating the most delay, with the RR (Rear Right) creating the second most delay.

I'm pretty sure I did this right. I measured each speaker distance to my head and then subtracted it from the farthest speaker (FR) to get the delay distance.

 

Does anyone use the Bass Focusing feature? What values do you use for it? Theres not a mathematical explanation for it in the manual like the time correction so I'm just trying to do it by ear.

 

So, what do you think?

 

What settings do you have for the X-over? and how did you get rid of that high pitched sound from the tweeders and the rears?

 

I'll tell you my measurements and numbers for comparison.

Distances from my head to the various speakers:

LF = 30"
RF = 46"
LR = 18"
RR = 38"

RF - LF = 16" = 1.2ms delay = 12 steps
RF - LR = 28" = 2.1 ms delay = 21 steps
RF - RF = 0 = 0 delay
RF - RR = 8" = .6 ms delay = 6 steps

My subs are in the rear appox. 1.2 meters away from my head, taking into consideration that the sound waves are likely bouncing off the back glass, as my subs face the rear. I calculate this to be equivalent to a 3.6 ms delay (36 steps) to all the other speakers to allow time for the subs sound to get to my head at the same time as the other speakers.

So, my settings, with Bass focus are as follows:

LF = 1.2ms + 3.6ms = 4.8ms
LR = 2.1ms + 3.6ms = 5.7ms
RF = 0ms + 3.6ms = 3.6ms
RR = 0.6ms + 3.6ms = 4.2ms

I recognize some will disagree with my measurements, however, I am measuring from my tweeter locations, in the A-pillars, which reproduce higher frequencies, and are, by far, the most localizable, imaging frequencies.

 

Are you guys measuring to the mids or the tweets in the front? Or do you have 2-ways in the bottom of the doors? You should be measuring to the tweeters.

 

I measured to the middle of the 2 speakers in the front. My time correction is slightly different than yours.

As for Bass Focus. The Alpine reps who set my old 9815 said they don't use it. It basically is a "time correction" but moves pairs of speakers together. It's for more fine tuning, personally I wouldn't use it unless you are really good at listening (use a real CD to adjust the sound).

My settings (measuring to the middle of the components)

FL-1.0
FR-0.0
RL-1.9
RR-1.8

Time correction is great. My 9835 is awesome. I think it sounds even better than the 9815 it replaced.