[Bass&Trouble]

^^ Depends on the speakers, mounting location etc.

Sending too much bass to speakers mounted in the dash is not a good idea. It will cause the dash to resonate.

You have LPF for what? You have a sub?

[Technocrat]

Yes,

EL 4.1(amp) on front dash, Pio 6X9s(HU) at rear. Sony 12 inch Sub(amp), Sony 4 channel amp

[drvhplyevraftr]

Originally Posted by Bass&Trouble

I would not advice running car speakers at the perilously low 40Hz considering that you have a sub. It will cause a lot of sub bass to be routed to the speakers. The most prominent negative effect of this will be noticeable in its midrange reproduction. The power handling will be greatly compromised. And, the subwoofer and component speaker will overlap over the 40-80Hz band and cause bass to sound poor. Besides, 20Hz to 40Hz is too small a band for the sub to be operating in. There will be very little to no information running to the sub with regular music.

Even if you set the HPF for speakers at 40Hz, please dont try to play the system as loud as you would with 80Hz.

What would you recommend the HPF on the JBL 75.4 amp (for the front/rear speakers) in my case then?. Currently the HPF on the JBL 75.4 is set to about 50 Hz.

Also the LPF (crossover) on the HU is set to 80 and the LPF on the sub amp (JBL 3501) is set to around 120. HPF on the sub amp is set to 0.

Please let me know the ideal settings in my case.

Thank you.

[navin]

Originally Posted by Technocrat

Hmm Is HPF at 125 & LPF at 80 a correct setting? I have tried both 80 & 125 for speakers & found that the fronts(EL 4.1) sound better at 125.

just a general rule of thumb; 4" drivers are happier XOed above 100Hz, 5" can be pushed to 80 and larger (read as 6") can be pushed to 60Hz (all summing the slope is 12db/octave). If you have control over the slope try 80Hz/18db vs 100Hz/12db and see which sounds better.

Originally Posted by Bass&Trouble

Even if you set the HPF for speakers at 40Hz, please dont try to play the system as loud as you would with 80Hz.

Originally Posted by drvhplyevraftr

Like you have said, I will turn off the HPF on the sub amp and lower to about 40 hz on the JBL 75.4 that are connected to the front/rear speakers.

There is very little musical energy below 40Hz. Besides the human ear is horrible insensitive to these frequencies so to really "hear/feel" music below 40Hz you not only need gobs of power but a lot of displacement (think large, big Xmax woofers). Now once you go this route you also need to damp everything pretty well otherwise all parts of the car will start vibrating / resonating starting with the door panels to the switches and door handles.

[dinu2506]

Originally Posted by drvhplyevraftr

What would you recommend the HPF on the JBL 75.4 amp (for the front/rear speakers) in my case then?. Currently the HPF on the JBL 75.4 is set to about 50 Hz.

Also the LPF (crossover) on the HU is set to 80 and the LPF on the sub amp (JBL 3501) is set to around 120. HPF on the sub amp is set to 0.

Please let me know the ideal settings in my case.

Thank you.

I would recommend the following. On the AVX 44, set the crossover at 120Hz. On the 75.4, set the HPF at about 100Hz to ensure that you don't lose any frequencies. On the 3501, set the LPF at about 150Hz again to ensure you don't lose any low frequencies (since only frequencies below 120Hz come to the amp) and the HPF at about 40Hz. This ensures that the sub gets a fair range to perform.

[drvhplyevraftr]

Originally Posted by navin

If you have control over the slope try 80Hz/18db vs 100Hz/12db and see which sounds better.

Now once you go this route you also need to damp everything pretty well otherwise all parts of the car will start vibrating / resonating starting with the door panels to the switches and door handles.

Originally Posted by dinu2506

I would recommend the following. On the AVX 44, set the crossover at 120Hz. On the 75.4, set the HPF at about 100Hz to ensure that you don't lose any frequencies. On the 3501, set the LPF at about 150Hz again to ensure you don't lose any low frequencies (since only frequencies below 120Hz come to the amp) and the HPF at about 40Hz. This ensures that the sub gets a fair range to perform.

Thanks everyone for the reply.

@navin - I dont have control over the slope. What would be the default 18db or 12db?. Sorry if it is a stupid question.
I have the doors damped. I am yet to damp the boot though.

@dinu - I will change the settings to what you have recommended and see how it performs.

[valhallen.282]

WHY would you set the HPF on the sub amp to 40hz don't you want any of the lower frequencies at all? 120hz is midbass let your in car speakers handle that at least bring the sub down from 20 to 100 hz. IMO just turn off the HPF on the sub amp. Unless your original installer put it there for a reason.

[drvhplyevraftr]

Originally Posted by valhallen.282

WHY would you set the HPF on the sub amp to 40hz don't you want any of the lower frequencies at all? 120hz is midbass let your in car speakers handle that at least bring the sub down from 20 to 100 hz. IMO just turn off the HPF on the sub amp. Unless your original installer put it there for a reason.

I doubt if the original installer knew head or tail of anything he was doing. Infact thats the kind of audio installers we have in hyderabad. The only name that goes around in team-bhp of good installer in Hyderabad is hamid and I am yet to meet him.

The guy who installed the HU kept the amplifier gain to high on the HU where as he should have kept it at off since I have an external amplifier. He was using the HU amplifier and was tuning the AMP. I am not even sure if there was any effect on the settings that he made on the AMP as the HU was using the inbuilt amplifier. There was absolutely no bass coming out of the speakers and the sound was so harsh. The gains on the external amp were kept at the lowest possible setting. I was just not happy with the sound I was getting and started fiddling around and made quite a few changes and I am pretty happy with the sound now. The bottom line is I seriously doubt if the installer has even a fraction of knowledge that I have in tuning car audio.

[khan_sultan]

My setup is: Front JBL comps (JBL GT5 500c), NO Rear speakers, + Sub: JBL CS 1204 + Amp: JBL GTO 504The amp is JBL GTO 504

The setting in the HU (AVX 44) are:

Amp Gain: Off
HPF: Through
X-over: 120 Hz

Here is a picture of my amp settings. Help me tune it.



Look forward to your help to determine what should each setting be (I prefer soft bass and clear vocals/instruments. I am NOT into heavy music but old hindi songs & ghazals & old english songs most of the time):

[ramie2400]

I recently tuned the AVX-814,i kept the HPF on "thru" and tuned the Illusion Components/speaker's HPF on the JBL 75.4,you can even do it vice-versa leaving the amp on Flat,only thing we get more flexibility tunning the Amplifier than the HU sometimes rest was set on LPF powering the GZ-30SPL on full swing.

Ramie

[drvhplyevraftr]

Thank you guys for your reply. However the more replies I get the more I am getting confused. I agree that you guys are trying to help me and I agree there are several ways that the system can be setup. But for the sake of my simplicity, lets just say that I keep the HPF on the system to ON since I have a sub (document says to set it to ON when sub is connected and Through when there is no sub).

The JBL 75.4 connected to the front and rear speakers have been set to HPF. Please tell me what would be the best frequency to keep it at such that I dont hurt/damage the speakers and I get decent bass out of it. I have set this currently at about 50 Hz.

The (LPF) crossover on the HU is set to 80 Hz.

The JBL 3501 monoblock is connected to the JBL GT5-12. The HPF on the monoblock is set to the lowest setting (earlier I had set it to around 30). The LPF on the monoblock is set to about 80.

Also let me know how to know if the amp gains are set correctly?.

Please help me and khan_sultan. Both of us have similar queries and I think he is also as confused as I am.


@ramie2400 - If I leave the HPF to through on the HU, please let me know:
What I should set on the JBL 75.4 amp (HPF/LPF/FLAT) that is powering the front/rear speakers?.
What frequency should be set on the JBL 75.4 amp?.
The (LPF) crossover on the HU set at (80/120/150)?
The LPF on the JBL 3501 monoblock?
The HPF on the JBL 3501 monoblock?

I dont want too much treble and would like more of bass output. Please help.

Thank you.

[dinu2506]

The simplest and most uncomplicated would be to set the crossover on the HU to 120Hz and leave the settings on the 75.4 to flat or off. On the 3501, set the LPF at any value greater than what was set in the HU, in this case any value above 120Hz. Setting the HPF on the 3501 has 2 advantages. One, there is no point trying to drive frequencies below 30Hz, since it will require enormous power and 3501 cannot do that. So why strain the poor guy. The other advantage is that the Bass Boost always boosts the frequency just above the HPF setting. Eg if you set the HPF at 30Hz, you can get a boost at slightly above 30Hz. In summary

HU - Crossover at 120Hz
75.4 - Front and Rear channels at "Flat"
3501 - LPF 130Hz, HPF 30Hz

Try this out. Play around with the Bass Boost and HPF on 3501 till you get the bass effect you desire. You can also try increasing the gain on the 3501 to the required level till you get a clean bass.

[drvhplyevraftr]

Originally Posted by dinu2506

The simplest and most uncomplicated would be to set the crossover on the HU to 120Hz and leave the settings on the 75.4 to flat or off. On the 3501, set the LPF at any value greater than what was set in the HU, in this case any value above 120Hz. Setting the HPF on the 3501 has 2 advantages. One, there is no point trying to drive frequencies below 30Hz, since it will require enormous power and 3501 cannot do that. So why strain the poor guy. The other advantage is that the Bass Boost always boosts the frequency just above the HPF setting. Eg if you set the HPF at 30Hz, you can get a boost at slightly above 30Hz. In summary

HU - Crossover at 120Hz
75.4 - Front and Rear channels at "Flat"
3501 - LPF 130Hz, HPF 30Hz

Try this out. Play around with the Bass Boost and HPF on 3501 till you get the bass effect you desire. You can also try increasing the gain on the 3501 to the required level till you get a clean bass.

OK. I will try this out. What should the HPF on the HU be set?. Should it be set to ON or Through?.
I will set the rear/front to FLAT on the JBL 75.4 amp. Do I need to change the frequency on this AMP?.
Please let me know. Thank you.

[navin]

Originally Posted by valhallen.282

120hz is midbass let your in car speakers handle that at least bring the sub down from 20 to 100 hz.

Originally Posted by dinu2506

HU - Crossover at 120Hz
75.4 - Front and Rear channels at "Flat"
3501 - LPF 130Hz, HPF 30Hz

Firstly I would recommend that you figure out how much bass your front (and rear) speakers can handle. The more they can handle the more your image will be in front of you. At the levels I listen to my 6.5" front speakers can easily handle 50Hz/18db. At louder levels I might push them to 63Hz/18db.

Once the front speaker's limited are known you work the sub to integrate with the front speakers. Depending on your taste, slopes available, and phase difference you might find that you dont need to LPF the sub at the same freq as you have used to HPF the front speakers.

Once the sub is done, bring in the rear as rear fill.

[drvhplyevraftr]

Also the amplifier gain on the HU has to be kept at OFF isnt? Please let me know if it is otherwise. Thank you.