Cross Over Frequencies - Explanation

[morch]

Hello,

I am relatively new to the home theater experiance. I recently pruchase a H/K AVR 147 with the Polk Audio RM6750 surround sound system.

After the initial set up, I ran the EZ set with the microphone from H/K. After watching the fist couple of movies, I thought the audio should sound more crisp. After reviewing the cross over frequencies from the auto set up, the cross over frequencies were 80Hz for the center channel and 100 Hz for the front and surround speakers. I reviewed the Polk manual, and this said the cross over frequency should be set at 120Hz.

The center channel and the surround speakers have the following rating....

Overall Responce: 100Hz -24kHz
-3db limits: 135Hz - 20 kHz

Question, If the overall responce has a lower frequency of 100 Hz, why is this not the crossover frequency?

Why did the receiver detect something different?

Does anyone have any suggestions for what to listen to in order to maximise the experiance of the home theater? I often find myself running the center speaker at a higher volume than the rest of the system. Is this common with other set ups?

Thanks.........

 

[Alex2507]

The E-Z thing will get you close but not right on. If the Polk manual says to set the X-over @ 120hz then do so. Then get one of these to adjust the channels.

http://www.radioshack.com/product/index.jsp?productId=2103668&cp=&sr=1&origkw=sound+level+meter&kw=sound+level+meter&parentPage=search

The overall response includes the sub and the X-over setting determines where your sub takes over. Having too much bass going to your speakers with the 80hz setting will muddle the sound. New word, I just made it up. Good luck and have fun.

Edit: Once you do this you will have enabled the center to do a better job of delivering dialouge. If you still need to bump up the adjustment on it, feel free. Lots of other people do the same to hear dialouge better.

 

[j_garcia]

100 or 120hz isn't going to make much difference to a satellite speaker, so whichever is available should work, however you do want to try to get it as low as possible because your sub should ideally not be playing too high up. The receiver is taking into account your room and how the response is with a given speaker playing, and since rooms and calibration software are not perfect, the receiver can only do the best with what it "hears".