[Rudra Sen]

Originally Posted by navin

Time Alignment is the next step up.

OK Navin, don't shout at me. I'm not at all a regular in this audio discussion and that's why the question. How do we do this time alignment thing with older head unit? Is there a way or not?

[agambhandari]

Originally Posted by DerAlte

How does that work? Do you mean use the rear speakers *only* for low frequencies, cutting out the rest with the LPF?

If the rear speakers are not capable of going low by themselves, it wouldn't help. Unlike in dieting, leaving out some of the stuff does not get one any gains!

The LPF will give mostly the Low Frequency waves to the Rear Speakers and attenuate the others.

Yes, the speakers also need to be able to give off the bass.
But applying LPF will alllow a more bass heavy sound at all volumes.

You can get the whole process here

[DerAlte]

Originally Posted by agambhandari

... You can get the whole process ...

Oh! Thanks, I learn something new everyday.

But, do you realize that with LPF you don't get 'bass-heavy music', rather ONLY bass? That would mean rear passengers hear only thump-thump and nothing else, right?

OTOH, *without* LPF everything will be heard together as it was meant to be. The 6x9s will make decent bass as is, albeit not as low as a sub.

[agambhandari]

Originally Posted by DerAlte

Thanks, I learn something new everyday!!!

But, do you realize that with LPF you don't get 'bass-heavy music', rather ONLY bass? That would mean rear passengers hear only thump-thump and nothing else, right?

Yes the rear speakers will mostly ''thump'' but in tandem with a nice pair of front speakers,it can be pretty good .
It won't be only bass, the higher frequency sound will only be attenuated (not killed completely)
at least better than trying to extract bass from smaller front speakers.(in the case without LPF )

[navin]

Originally Posted by agambhandari

A good pairs coaxials at the back can be used provided the HU is a good one.

Check if the HU can apply LPF(Low Pass Filter) to the rear speakers, it will make the Rear Speakers a "Pseudo-Woofer" and gove you acceptable levels of bass.

If he LPFs a full range driver the rear speaker will produce only bass ( in the case of a 6x9 it would be mid-bass). LPF alone won't make the bass come from the front. You need judicious tuning that some amplifiers provide and even that just gives a semblance of bass. If one listens closely you can hear the bass is coming from the rear. Bass is odd in a way, you feel it as much as you hear it.

Originally Posted by Rudra Sen

OK Navin, don't shout at me. I'm not at all a regular in this audio discussion and that's why the question. How do we do this time alignment thing with older head unit? Is there a way or not?

Where there is a will there is a way. If for some reason you need the OEM or older HU you can add a processor. But really the most economical way is to tune judiciously.

You remember the old adage "the presence of bass must not be obvious, but it's absence should be". If you tune any system with this in mind you should trick your ear to ignore the location of the subwoofer. In a car it is a bit more difficult but not impossible. What do you think we audio fanatics did before DSP came along. We relied on ears and common sense.

You will surprised what a reduction of 2db or a change of crossover frequency by 10Hz can do. Take your 3 favourite tracks and listen. Tune. Then listen again. It is just that simple. Just like when you take pictures, you look, compose in your head, then shoot. In audio too you listen, visualise what you need to do, then do it.

[mi2n]

Originally Posted by navin

Start with a HU that has 3 pairs of pre out (so you can add amplifiers later) and if possible time alignment. Get the 4" and 6x9s for now. When the budget permits, add damping, a well tuned subwoofer and the time alignment (optional).

Sorry for the delayed update, but got the following installed as per Navin's guidance:

JVC KW R500 : 2 Pre-outs only, has HPF/LPF
JBL CS4 4" in dashboard and
JBL GTO 949 6x9s on a rear MDF tray.

Results :
1.The soundstage at the rear is way better than my setup (contemplating an upgrade myself), but somehow I'm getting the feeling that the HU is not being able to drive the 6x9s to their optimum potential.
2. The soundstage at the front is however not any better than my current cheap Blaupunkts provides, the CS4 even manages to sound a bit harsher.

Outcome :
This Beat D is getting an Amplifier and Sub-woofer pronto!
Budget for Amp + Sub + wiring ~ 11k, the lower the better.
Contemplating a 4 channel Amp and an 8" subwoofer.

Queries :
1. Placement of the sub-woofer? I've read that sub-woofers can be tucked under the front seats, that would be ideal. However, given the clearance under the Beat's front seats, one wonders how a sub can go in there? Afterall, improving the frontal soundstage is the target.
The next choice would be to fit the sub on the rear MDF Parcel tray in between the 6x9s. There is even marked provision for the same in the tray. What are the pros and cons?
Only as the last option would we put(reluctantly) the sub in the boot in an enclosure. The bootspace, albeit already tiny, is required. That is why we originally wanted a no sub setup and that is why we will settle for a 8" sub now. Will a sub in the boot be able to affect the front soundstage? There's enough bass for the backbenchers from the 6x9s already.
2. Which sub and amplifier would fit in the given budget? Would like a 4 channel Amp so that the rear 6x9s could use it too.

Thanks and best regards for the festive season!

[navin]

Originally Posted by mi2n

2. The soundstage at the front is however not any better than my current cheap Blaupunkts provides, the CS4 even manages to sound a bit harsher.

1. Placement of the sub-woofer? I've read that sub-woofers can be tucked under the front seats, that would be ideal. However, given the clearance under the Beat's front seats, one wonders how a sub can go in there? Afterall, improving the frontal soundstage is the target.
The next choice would be to fit the sub on the rear MDF Parcel tray in between the 6x9s. There is even marked provision for the same in the tray. What are the pros and cons?
Only as the last option would we put(reluctantly) the sub in the boot in an enclosure. The bootspace, albeit already tiny, is required. That is why we originally wanted a no sub setup and that is why we will settle for a 8" sub now. Will a sub in the boot be able to affect the front soundstage? There's enough bass for the backbenchers from the 6x9s already.
2. Which sub and amplifier would fit in the given budget? Would like a 4 channel Amp so that the rear 6x9s could use it too.!

If you find the sound too harsh try dropping the treble by 2db. This is the unfortunate part of the Internet. We can't determine you taste in sound.

You can get some slim subwoofers that go below the seat but these do not produce any real bass. They produce more mid-bass but this could improve the subjective balance of the overall sound.

If you get a 4 ch. amp and use it for the subwoofer and rear speakers the balance of sound will shift to the rear. As it is the bigger 6x9s are more efficient than the small front speakers. I would recommend using the amp to drive the front speakers instead and also using the HPF on the amp to limit the bass going into the front speakers.

[tjacob]

Hello Navin,

I dunno if this is appropriate to ask but you seem to have a thorough knowledge of the workings of car audio equipment and sound in general. I'm sure all this is from years of collective knowledge from various sources, educational or may be your own understanding & research but if you were to point a beginner like me to a good source (website or even books), what would it be ?

Thanks in adv. for any help.