mate was saying that his JVC h/u has function to make the subs hit a second before the music plays. that way by the time it reaches him the music from the speakers and the subbass integrate. has anyone heard of this before?

ive been looking to upgrade my JVC in the sig to a alpine. would an alpine h/u be able to do something like that? im curious cause delayed subbass annoys me .

i have the JL audio 12w1v2 in a JL ported box. as for everyone else this only happens when listening to something more dynamic. i have also tried different sub positioning in the boot.

are there any other suggestions?

thanks

Alex

It's called Time Alignment (or 'TA'), and most mid-to-high spec head units have it.

cheers, will have to look at something like that, cause its annoying as hell

can we move this to the beginners section?

your JVC deck wont do that, and its difficult to find "time alignment" or "delay" in headunits under about $5-600. the Alpine 9887 will do what you ask.

However, you can overcome your issues of "group delay" without time alignment. Quite probably, the issue is related to the box. Have you tried using a sealed box? was the ported box built especially for the sub, or was it just a generic JL ported box? have you tried swapping the + and - on the sub?

give that a go, keep moving it around and facing it backwards and forwards and see how you go.

honestly, I'd try a sealed box first though...

now now, no need to bite, i think this can go in here just as much as it can go into the beginners section.

yes i already realise that my JVC deck doesnt do that. and yes, i WAS asking whether alpine will do that. are there are any other alpine models worth having a look at with similar function between rrp300 and the 9887?

i havent tried swapping the terminals on this particular sub but i HAVE done it on my old JL sub and it didnt really do much except make it sound worse.

the ported box is the generic one that was sold with the sub, so ill have to measure it up to see if it has the required volume. i realise that ported boxes are more unforgiving on size than sealed. the only problem i see with a sealed box is that the sub is only 200WRMS and while its a fairly efficient driver the best quality ill get out of it is with a ported box

thanks for your input

sorry 92gen2, didnt mean that to sound rude or snooty (snooty...snotty?) - it was meant for the moderators

you're probably right about ported giving you more output, but its also the likely cause of the group delay you are hearing. Why not give it a go in a sealed enclosure (maybe 3db quieter but sounds less like crape), or post up the specs (Qts, Qes, Vas etc) so someone can model them and see what the best box is for that sub.

I suggested swapping the speaker wire at the sub because this changes the phase of the sub - instead of the cone pushing out at a given moment, it now pulls in. Do a search for phase in this section to get some more info.

As for headunits, you could try looking in the "for sale" section here, as units with time alignment do come up regularly for sale, and cheap too, if you know what you're looking for.

I'm not convinced that time alignment will solve all of the problems you are hearing, thats all...

good luck!

You must miss Victoria VIP, ya grumpy bum

92gen2 - it might also be an issue with the port on your box. With a ported sub, the port size and length also come into play, as well as the box size. If the port is not correct for your sub, you may get 'huffing' type sounds, or muffled bass. Would be worth checking those specs as well

Check this link - LINKY FOR YOUR SUB

it has the PDF file which tells you the correct dimensions for your box, and port size etc etc