Separation

[dragnix 5,000+ posts]

bass from the rear? i thought bass isn't directional

 

[Techchild 10+ year member]

bass from the rear? i thought bass isn't directional

I whent out and played around with the eq a bit and it sounds a little better.

If you were local I would let you hear what I mean.

 

[squeak9798 5,000+ posts]

@ dbfan187: yes if u wanna delay one mid compared to the other, but he wants to bring the bass up front...TC is the only way to tweak it right

Wrong.

It's likely a subwoofer integration issue which can be cured with proper level adjustment, crossover selection, phase adjustment (yes, phase for the subwoofer matters, also phase adjustments don't delay anything) and potentially some EQ work. Time alignment is FAR from the only way to fix an integration problem, and at this point I would presume it's the least of his worries because I'm guessing that the proper attention hasn't been given to the aforementioned. Time alignment may or may not be necessary, but the items I mentioned are absolutely necessary for proper integration.

OP: What does the rest of your system consist of ? Because for proper subwoofer integration we can't focus solely on the subwoofer.....the setup of the front stage is also going to play a roll. And what sub setup are you using (i.e. what sub in what enclosure) ?

 

[JimJ 5,000+ posts]

Could be a lack of midbass problem...

 

[mile098 10+ year member]

Wrong.
It's likely a subwoofer integration issue which can be cured with proper level adjustment, crossover selection, phase adjustment and potentially some EQ work. Time alignment is FAR from the only way to fix an integration problem, and at this point I would presume it's the least of his worries because I'm guessing that the proper attention hasn't been given to the aforementioned. Time alignment may or may not be necessary, but the items I mentioned are absolutely necessary for proper integration.

OP: What does the rest of your system consist of ? Because for proper subwoofer integration we can't focus solely on the subwoofer.....the setup of the front stage is also going to play a roll. And what sub setup are you using (i.e. what sub in what enclosure) ?

if its a matter of midbass lack then all of what u just said stands, but if its just a matter of the subbass then i dont see how u can fix it with xover selection phase adjusment or eq work? all of that will help to a certain extent but cant alter the physical position of the woofer in the back..delaying will do the trick and is the most accurate method of bringing the bass up front..i do agree that messing with the phases might help a bit or eqing it, but TC is a much more efficiant way...if the problem derives from the mids being cut off too high, work on that first, if not then...

 

[squeak9798 5,000+ posts]

bass from the rear? i thought bass isn't directional

The sound is omnidirectional radiating from the driver. If you've ever looked at a frequency response graph for a driver, you'll notice that in the lower frequency register there is virtually no change in response from on-axis to off-axis placement.

But properly setup, it should "sound" like it's coming from in front of you. Improperly setup, you'll notice the sound coming from behind you.

 

[jmanpc 5,000+ posts]

I've found that perhaps the best way to 'pull' the bass up front is to have very strong midbass. With that, the sub (when properly adjusted) should just melt into your front stage.

 

[Immacomputer 10+ year member]

@ dbfan187: yes if u wanna delay one mid compared to the other, but he wants to bring the bass up front...TC is the only way to tweak it right

No, it's not the only way. Setting the low pass filter and getting a stronger midbass presence up front will help pull the sub stage up front. Also, level adjusting will have a positive effect if the sub is over powering the front stage.

 

[JimJ 5,000+ posts]

bass from the rear? i thought bass isn't directional

Subbass isn't directional, but we don't live in an anechoic chamber //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif Well, most of us...some people that post on this forum probably should...

Put a speaker, any speaker, in the real world, and things get less than perfect fast.

 

[squeak9798 5,000+ posts]

if its a matter of midbass lack then all of what u just said stands, but if its just a matter of the subbass then i dont see how u can fix it with xover selection phase adjusment or eq work? all of that will help to a certain extent but cant alter the physical position of the woofer in the back..delaying will do the trick and is the most accurate method of bringing the bass up front..i do agree that messing with the phases might help a bit or eqing it, but TC is a much more efficiant way...if the problem derives from the mids being cut off too high, work on that first, if not then...

Disagreed with everything you've just said.

Not accurate.

For example; Please explain how time alignment is going to fix a 30db difference in output level ? Please explain how time alignment is going to fix all of the frequency response anomolies that could cause issues with integration ? Please explain how time alignment is going to fix the transition from midbass to subbass ?

You can't, because it doesn't; But the issues I mentioned will. Yes midbass setup plays a roll aswell, which is why I asked him to explain the setup of the rest of his system aswell. And time alignment may help some also (it may not, however, be necessary). But you have a fundamental misunderstanding of proper system setup if you think time alignment is the most important or only factor in proper subwoofer integration.

Also, I forgot to mention another aspect; Sound deadening. Rattles and resonances in the rear will pull the subwoofer to the rear. How much sound deadening has been done of the vehicle ?

 

[T3mpest 10+ year member]

if its a matter of midbass lack then all of what u just said stands, but if its just a matter of the subbass then i dont see how u can fix it with xover selection phase adjusment or eq work? all of that will help to a certain extent but cant alter the physical position of the woofer in the back..delaying will do the trick and is the most accurate method of bringing the bass up front..i do agree that messing with the phases might help a bit or eqing it, but TC is a much more efficiant way...if the problem derives from the mids being cut off too high, work on that first, if not then...

phase control and level adjustments are much better for bringing bass upfront than time alignment. According to my ears as well as most of the better tuners out there. Rattles will give a sub away fairly easily too. Also, for a sub that's mounted IB the actual sub needs to be quiet during the end of it's stroke. Suspension noise can be an issue.

 

[Techchild 10+ year member]

My front stage is two kenwood 5.25s that is probally why i don't have proper mid bass and sub bass merging. they came with the car and I don't know excatly there freqency range is but I have the high pass on them set to 80 and low pass on the subs at 80 also.

I played around with the eq some more and now it sounds a lot better but still a faint sound of the subs coming from the rear

 

[mile098 10+ year member]

i still say the best results come with TC although yes adjusting the xover may help...but then again if your midbass is not in a panel or a well preperaded door, theres no point in going under 60Hz or even 80 with it...at least from my experience

edit: just noticed all the quoting, all of what i wrote is coming from the persumption that the midbass is cut low enough to make the trasnition...mine is at 63Hz the sub play to 70...

if u dont need the TC good for u, i find that it works wonders for me...

and if i remember corectly the OP didnt mention anything about having a gap just that the bass is coming from behind...two different things in my book, dont know for you all

 

[Techchild 10+ year member]

also could it have anything to do with me removing my rear 5.25's? should I put my rear fill back in?

 

[T3mpest 10+ year member]

also could it have anything to do with me removing my rear 5.25's? should I put my rear fill back in?

That'll probably just draw even more sound to the rear. Anyway first thing I'd do is play with the crossover. Try a steeper slope as well as a lower xo frequency. When you get the best blend you can stop. Next step would be phase adjustment. If your amp or hu can't do continual phase adjustment then simply go to your amp and switch the positive and negative speaker wires. Then relisten to your setup and see if the bass sounds better or worse. Keep it whichever way it sounds better. Then do the same to your midbass. At that point my last suggestion would be simply turn the sub down. Usually the last step works 99% of the time and is usually the culprit.