nom

I don't know if anyone knows this particular head unit - the Alpine somethingsomething 7998? Anyway, seriously complicated. Ye gods . It's a bit of a change after my old Nak45, which was one of the units that goes for my usual idea that a volume **** makes things quite complicated enough, thanks very much . This thing has an active crossover (for sub, rear & front), a parametric equaliser, a 'time shift' thingy (with additional bass focusing engine ?!?!) and then the usual gadgetry on top.

Anyway, I was wondering if anyone has any experience in setting up this sort/stlye/complication of thing... The active crossover I'm happy with (have one anyway, now unused ); the parametric doobrie just takes a bit of getting used to with the particular speaker set up, but the timing malarky really has me thrown. I've managed to adjust the whole lot so it no longer sounds pants (the word I'd use to describe the sound when I first installed the system).
There must be a knack. And someone must want to give it to me

I thought the order of attack here was crossover, timing, bass shift, equaliser. Seems the way as the first affects the next blah blah all the way down.

I've done all the calculations for using speed of sound, etc. to set it up as 'technically' correct, but as usual with these things, technically correct doesn't really mean much. The bass - as usual - is the really hard thing to set up. Vocals, guitar, etc. I can get sounding better than I thought would be possible in a car, but the second any bass starts coming through, we're back to 'pants' again. The subs seem out of phase, but by 90 degrees or so, rather than 180 - switching the phasing of the subs by 180 doesn't make much difference to the sound, except that one way round the phasing is cancelling out the bottom end & enforginc the upper bass, the other phase enforces the lower & not the upper.
Have I missed something obvious here? The crossovers which will impact all of this have the subs crossing over a fair bit with the front speakers at the upper end (they're 7" speakers in the doors & go pretty low) & I'm wondering if this is why the cancellation is there (at the upper frequencies in one phasing). I could probably get there in the end, but I've been at it for nearly 3 hours so far & things are moving rather slowly...

Sorry for the hugely long question, but I thought I needed to put a bit of explanation in there!

Si.t

sounds like a bit of time wave adjustment needs to be done, and this unit dosen't do that everything else, mind if all else fails i'll have it...

This link explains wave alignment fairly well. its a pdf manual by the way)

cheers

[Edited by Si.t - 3/5/2003 6:50:17 PM]