[rahuls21297]

Hi,

I have started to update myself on car (Swift) audio systems so am quite new hope you guys would bear with me. With this note the specs of my ice are:

HU: Pioneer 6950
Speakers Front: JBL 607c (Comp)
Speakers Rear :TS-a6982s
Woofer: Ts-w307d4
Amplifier #1: Pioneer gm6300f connected to front & rear speakers.
Amplifier #2: Alpine f586 amp.

I recently changed the connection of my woofer from single coil (4 Ohm) to dual coil parallel connection (2 Ohm) which has certainly improved the bass, however i wish to change the alpine amp as it is fake i am told.

My question is can i use this existing amp anyway, if no then can anyone suggest me a better amplifier.

Also i am told that one should not use the woofer on one coil can anybody pls explain what this means.

Thanks in advance

[saintsinner]

i'll tell what i can -

Alpine without bill & Warranty, is definately local. and is found everywhere in delhi/NCR markets.
It's a piece of c**p but that would again depend upon the built quality.

go in for a monoblock classD from Pio, should set you back by about 10K, but its worth it.

[navin]

Originally Posted by rahuls21297

HU: Pioneer 6950
Speakers Front: JBL 607c (Comp)
Speakers Rear :TS-a6982s
Woofer: Ts-w307d4
Amplifier #1: Pioneer gm6300f connected to front & rear speakers.
Amplifier #2: Alpine f586 amp.

I recently changed the connection of my woofer from single coil (4 Ohm) to dual coil parallel connection (2 Ohm) which has certainly improved the bass, however i wish to change the alpine amp as it is fake i am told.

My question is can i use this existing amp anyway, if no then can anyone suggest me a better amplifier.

I hear the Pio 7300M is avaialble for Rs. 7500 in grey. If that is true it good VFM and will go a good job with the 307.

Alpine, to the best of my knowledge did not ever make a 586.

[rider60]

dude try and get a JBL GTO 301.1 MONO from grey, it should not cost you more than 8200 with good negotiating skills!

[rahuls21297]

Hi guys,

I am using a Pioneer P80 RSii HU in a CRUZ with 6/12 Kappa front components, rear Pioneer coaxials & a 12 inch pioneer sub in the boot with passive setup.


My fronts are crossed at 80Hz/ 6db, Rears at 100Hz /6db and Sub at 80z 12db

I have two issues:

1. My bass is not integrating with my fronts and sounds out of sync when i try to change the front to 12 db the bass reduces further, with the rears if I change the octave to 12db the bass increases. In both the situations the bass impact remains from the rear.

I have checked the polarity and wiring which are ok. The TA settings also are untouched.

2. The output of bass in car is tripled when I open my front doors or window pane.

I want to know why the bass is increasing so much when I open my car doors as it does not happen in my other at all. Can anybody please tell me what am I doing wrong as its driving me crazy.

thanks

[Bass&Trouble]

Thou art a victim of standing waves. You are sitting in the null point formed when the windows are up. There's hardly much you can do except roll down the windows a bit to enjoy the bass. Or add another subwoofer.

[rahuls21297]

Originally Posted by Bass&Trouble

Thou art a victim of standing waves. You are sitting in the null point formed when the windows are up. There's hardly much you can do except roll down the windows a bit to enjoy the bass. Or add another subwoofer.

Can you please elaborate? I am looking in for a solution

[DerAlte]

Which way is your sub facing? Try changing that and see if it affects you in the driver seat.

[rahuls21297]

Originally Posted by DerAlte

Which way is your sub facing? Try changing that and see if it affects you in the driver seat.

I have tried positioning the woofer to the rear seat and towards the boot, whilst doing so the bass further reduces.

i have positioned it towards the left side facing towards the part other then facing the boot or the rear trunk, this results in an increase in bass. But even at this place cancellation is there but the bass keeping my windows and doors up increases.

Do you think increasing one more subwoofer can resolve the issue because in any case by increasing one more subwoofer cancellation will still exist.

Can anyone please tell me why is it happening in one sedan and not in another?

I hope its nothing to do with the equipment installed in my car??

[DerAlte]

What B&T was trying to point out - standing waves - is a phenomenon that is happening in your situation. This is not the same for every car or equipment. Nothing wrong with your equipment.

To understand standing waves, visualize a sine wave. It just happens that in your car, with the sub facing rear or front, the standing wave (because of constant reflection in the car) is in such a way that 180deg (where the sine wave crosses 0; NOT bass=0) is happening just near the driver seat. When you open the window or door, the standing wave ceases to exist. Similarly, when the sub is facing either side, the reflections don't seem to be causing a standing wave. In another car, this may or may not happen because the other car may be longer or shorter inside (in acoustic wave terms).

Adding another sub will cause the standing wave to be skewed / cancelled.

This is not 'bass cancellation', like on parcel shelf or opposite doors, that happens when 2 speakers are playing the same wave in anti-phase due to incorrect connection.

[rahuls21297]

Originally Posted by DerAlte

What B&T was trying to point out - standing waves - is a phenomenon that is happening in your situation. This is not the same for every car or equipment. Nothing wrong with your equipment.

To understand standing waves, visualize a sine wave. It just happens that in your car, with the sub facing rear or front, the standing wave (because of constant reflection in the car) is in such a way that 180deg (where the sine wave crosses 0; NOT bass=0) is happening just near the driver seat. When you open the window or door, the standing wave ceases to exist. Similarly, when the sub is facing either side, the reflections don't seem to be causing a standing wave. In another car, this may or may not happen because the other car may be longer or shorter inside (in acoustic wave terms).

Adding another sub will cause the standing wave to be skewed / cancelled.

This is not 'bass cancellation', like on parcel shelf or opposite doors, that happens when 2 speakers are playing the same wave in anti-phase due to incorrect connection.

Appreciate your help DerAlte!! Can you tell me what is the suitable solution to this issue, do you think dampening can help.

[DerAlte]

Originally Posted by rahuls21297

... do you think dampening can help.

Damping is for removing rattles & buzzes and reducing external noise (do you mean you haven't done damping yet?). Won't help for removing standing wave.

The only solution is 2 subs, or careful positioning of sub patiently.

[navin]

Originally Posted by rahuls21297

Appreciate your help DerAlte!! Can you tell me what is the suitable solution to this issue, do you think dampening can help.

Simplest way is to filter it out.

If it is below 30Hz and your sub amp has a rumble filter use the rumble/subsonic filter to roll it off. If the standing wave in above 80Hz let the front speakers roll of (HP) at say 80Hz and the LP the sub at say 60Hz. You get the picture.