Crackeling sound from tweeters (1 Viewer)

[VossSVT]

Hello, I hope some one can help me with this one. I just put together a middle grade 7.1 system to replace my beginer out-of-the box system and I'm having a serious issue. When listening to FM radio at high volume with the subwoofer at medium volume the tweeters in my tower speakers (all seven) make a horrible crackeling sound. The sound only occurs when heavy bass notes drop and stops when the subwoofer is turned down. This problem does not ocurr when playing CD's, DVD's, or TV/Cable, I can blast the speakers until my house shakes (I had to try it once) and the tweeters are fine. I can listen to a soung on the radio and have the crackeling sound of tweeter death occurr and then put in a CD of the same song and the tweets will be fine. I'm very confused by this and can only figure it has to do with FM stations. ????
If anyone can tell me what the heck is going on and even better tell me how to fix it I would really appreciate it. Thanks!

 

[chuckg]

If you are listening to FM, and turn the sub up you get crackling, then turn the sub down and the crackling stops? Is that it?

Is the sub powered? (has it's own power cord) Are you changing sub volume on the sub itself, or in the receiver menu settings?

Just trying to narrow it down some....

 

[VossSVT]

Yes the crackeling/distortion seems to only occur when the sub is at moderate volume and goes away (or is not noticeable) when the volume on the sub is turned down or the sub is turned off. The sub is powered and when I have tried adjusting the volume on the sub itself and on the receiver in trying to fix it and I am having the problem with both. I have chatted with others that seem to believe it is soley an FM reception issue. Would you buy that?

 

[VossSVT]

Yes, thats it but only when listening to FM radio. The problem does not occurr when I am listening to CD's, MP3's, DVD, or Cable/TV.
The sub is powered and I have tried both adjusting the volume on the sub itself and the volume level on the receiver.
Thanks for the help!

 

[David Willow]

Listing mode different for FM?

Have you calibrated your speakers? You shouldn't have to turn the volume on the sub up and down. Calibrate it once and forget it.

 

[chuckg]

With a powered sub we can rule out any distortion produced by the sub using all the power from the main amp, leaving none for the tweeters.

I wonder if the sub amplifier is emitting so much RF noise that it is disturbing the FM reception? Try moving the sub far away from the FM receiver - even get a longish cble and put it in a different room on a different electrical outlet if you can.

We'll get this thing figured out!

 

[VossSVT]

Thank you I will try moving the sub further away from the receiver and see if it makes any difference. Thank you again for your help.