Subwoofer preout/cord

[kyheng]

I'm using Pioneer 5750 and all the pre-outs are used. To sub 1 is using the sub output. Now is set to 80hz on LPF, now with this coil added the voice is at minimum, without it the voice can be heard when turn to high volume

 

[DJThoRmented]

Sub got voice? Very dangerous... something is wrong somewhere. Sub must not sing, that's what happened to my friend who had a 5 channel amp but running it at 4.

Go check with installer/reseller

 

[kyheng]

The sub is not sing, only the LPF from the amp cannot filter out all the voice. That's disadvantages of using 2 channel to drive a sub without using pre-amp or e-crossover.

 

[cacin]

Well, you can try to use a 2 channel amp to power the sub without pre-amp or e-crossover. You can feel the bass abit softerand the sub moves very fast, sometimes until the voice coil disallocated. Then you try adding a coil to the sub, you can feel the bass is harder a bit and the sub movement slower.

This just proves that the sub is receiving high freq. When the speaker diagphram moves fast, it means the sub is trying to reproduce a high freq signal. When, it moves slower, it is trying to reproduce a low freq signal.

You're saying that your HU has LPF set at 80Hz. That would be a good enough crossover point. However, what is the slope for the HU LPF? An -18db/octave is the lowest for a sub LPF. The higher the better. If the slope is lower than that, you might hear some midbass signals which has voice in them.

 

[kyheng]

THe HU is -18. The main problem is comes from the amp, it just can't filter out all the high frequencies. Add a coil cost only rm80, but an crossover cost rm3++ What for get a crossover that only can be tuned when the car is stopped as my HU can set the fader?

 

[DJThoRmented]

The sub is not sing, only the LPF from the amp cannot filter out all the voice. That's disadvantages of using 2 channel to drive a sub without using pre-amp or e-crossover.

Hmmm... 2 channel amp also makes sub sing... you items need to be send back lah. I think you LPF filter on the amp ain't working well.

I've had my share of no pre-amp/XO but my sub still don't sing.

Then when I had active XO, the subs went smoother.

Now, all from HU coz its built in and I don't have to open the door under the wet rain, blazing sun or chilly nite to adjust and my sub STILL don't sing and I am still running the same amp for the sub. Haih...

 

[kyheng]

Anyway my amp is a second hand amp, so I cannot expect much from it. If the amp cannot filter out all the voice, then I have to find a way to solve it.

 

[Zenn]

the HU LPF cant go lower than 80hz ka...? even at 80 lpf also shouldnt be any voices coming thru, are u sure that LPF is on..?

 

[cacin]

THe HU is -18. The main problem is comes from the amp, it just can't filter out all the high frequencies. Add a coil cost only rm80, but an crossover cost rm3++ What for get a crossover that only can be tuned when the car is stopped as my HU can set the fader?

Hi kyheng,
I agree with you that adding a coil is cheaper.
What I do not understand is, if the LPF from your hu is set at -18db/octave at 80Hz, then, the signals that goes to your amp should be lowering at 80Hz. There is no need to use the sub's LPF if your hu already has one. However, you can use them both to get a steeper slope (higher than -18db).
Like what some of the guys mentions, is the LPF actually on? Or was the correct RCA connected to the sub? For your model of HU, you need to set something to SW1 I think. Haven't got the chance to own one. :cry_smile:

 

[kyheng]

The LPF from HU and amp is on, the voice that comes out from the sub is minimum, only you put your ears very near to it you can hear it which I not that happy with it. Anyway all the problem solved so I just leave it like this.

 

[DJThoRmented]

Very unstable situation you have there. Be extra careful young one.

May the force be with you.