Setting Crossover Frequncy in AVR

[manoj.p]

I think this is beaten to death, but there are couple points to understand.

Localization: Approximately 80 Hz and above, we can localize the sound where its coming from. Hence you will see the recommendations to cross over to subs 80 hz and below. Thats the ideal situation. Above that, should be produced by the speakers.

Now the -3db point. Speakers are designed to have flat output for its range. The -3db point is the frequency at which its output is 3 db down its rated output. -6db point means the output is 6 db down at that frequency. So, if a speaker has -3db at 150 Hz, it means it will continue to have less output below that frequency. To have consistent output in a Speaker + sub system, speakers having -3db point below 80 Hz works better. Below 80 Hz, sub takes over and the output is maintained.

Now, coming back to your specific case because your speakers have -3db point at 150 Hz.

Option 1: cross over your speakers at 150 Hz. Yes, some sounds will localize, but you will hear the full spectrum. This is assuming your sub can produce sound above 150 hz.
Option 2:cross over your speakers at 80 hz. Sound will not localize, but there is big dip in the 80 to 150 hz range.

Honestly, I would prefer option 1. Yes, its less than ideal, but better to hear all the sounds than missing out. In future, when you upgrade your speakers, then you can set the frequency to 80 hz. Till then, enjoy your system.

 

[ssf]

Am not convinced.

If that was the case, my sub would be silent in stereo mode as stereo does not have point one.

Now what I think happens with lfe +mains is that full frequency is sent to mains and anything below the crossover is sent to the sub. This means that if one has a bookshelf or a satellite, they will be trying very hard to produce the full frequency which obviously will be beyond their capabilities and this will end up ending up taxing both the bookshelf's and the amp.

However, trust your ears and your liking and set the um settings accordingly.

After some reading and some experimenting, I now know that LFE or LFE + Mains settings are applicable only if the fronts are set to large.

 

[newlash09]

I would recommend to place the sub woofer below the centre speaker ( in between the front L & R speakers that is ). And set the cross over to 160hz, for a seamless integration. The localized feeling of the sub woofer becomes predominant when it is placed closer to the listening position, than to the front three speakers. So, having it below the center speaker, will keep it sounding bang in the middle of the soundstage, and the localized feeling is reduced to some extent, though not completely eliminated.

The LFE channel contains audio frequencies between the 200 to 3 hz frequency band. It is separately coded in dolby as .1 sound track.

So when the sub is set to LFE - all the LFE effects upto 200 hz, are sent to the subwoofer only. If the sub woofer is set to 160 hz in your case, even an 190 hz signal if encoded in the LFE channel on a dolby disc will still be sent to the subwoofer, though it is theoretically above your set crossover frequency.

And when we select sub woofer as LFE + Main in the above scenario, the same 190 hz signal will be sent to both your sub woofer , as well as your front three speakers. However, please do bear in mind that only frequencies above the cross over frequency are sent to the front three channels. Hope this helps.

As something to bear in mind, please do not set your cross over below the 160 hz mark. Please bear in mind that we usually have normal drivers and high excursion drivers. A high excursion driver of 3.5 to 4 inch, can get down to 90hz ( at -3 db ), but a non high excursion driver of the same size cannot. So, to avoid damage to the driver at high volume levels, please set the cross over between 160 to 170 hz. Depending on your room acoustics, you will have experiment the cross over above 160 hz only. The same exact system as yours, in a different room will have a slightly different cross over by upto 20 hz. So, please experiment and enjoy your new system. Cheers..hyeah:

 

[Arunnavo]

When you set the crossover below 80Hz, the sound would be omnidirectional, meaning that you would feel the bass, but you can't really tell that its coming from the subwoofer. If you set the crossover higher, then those frequencies would also be produced by the subwoofer, but it would be directional; meaning that you would then be able to identify that those frequencies are coming from the subwoofer. (sorry if you knew this info already)

 

[Cooladitya007]

Hi i bought JBL Cinesystem recently. (AVR : JBL AVR101 & SPeakers : JBL Cinema 510)

Frequency Response according to Spec Sheet:

Frequency Response of Satellites : 150Hz 20kHz (6dB)
Frequency Response of Subwoofer : 46Hz - 250Hz (6dB)

What is the significance of -6dB?

Please help me in setting correct crossover frequencies in AVR.
Default was 100Hz for all the speakers and sub. But i changed it to 200Hz(which is maximum) after reading some stuff online and according to my understanding.

Thanks in advance

Hi l, sorry for bumping old thread but can you please share your experience of Jbl ht.
Thanks