Bass Management Confusion

Help Me.

I have an ICBM between a Sony TA-P9000ES and a 5 channel amplifier. Unfortunately, I don't get hear (or see using an SPL Meter) bass when running the AVIA bass management calibration for the left surround (LS) speaker. The right surround speaker works as anticipated. I have the pre/pro set for all speakers to large (no bass management). I have the cutoff frequency for the Right/Left Surround speakers set for 120 Hz. All of the other speakers appear to work as I anticpated. I do get freqs above 120 Hz or so out of the left surround.

Does anyone have any suggestions to help me solve this problem? Could I have made a cabling mistake? Is the ICBM broken? Any help would be appreciated.

Try switching your surround speakers. Put the one that works on the bad side and see if works. If it does, then it sounds like you have a problem with the speaker.

To check if it's the ICBM, reverse the surround channels on the unit. You already said one side works. If you switch it, it will show if the other side will work while driving the other side.

Good Luck!

[This message has been edited by Jason J (edited January 14, 2003).]

Thanks for the help Jason, I'll try that tonight.

However, I think the speaker is ok because it appears to work properly above 120 Hz (the ICBM set crossover frequency for the right/left surround). I just don't get bass redirected to the subwoofer when the AVIA disk sends low frequencies to that channel.

Boy, I really should read these posts more carefully before jumping in with a response. Now as I reread your post, you're saying that all the bass for the surrounds is being sent to your sub. Why? What kind of speakers are you using for surrounds? Bass frequencies, according to the THX standard, become directional above 80Hz. Some people will say bass frequencies become directional as low as 50Hz. That means the bass from the surrounds will appear to come from the direction of your subwoofer and not the surround speaker. That could get a little annoying.

For most movies, your surrounds won't see frequencies that low. Multi-channel music is a different story. However, with most of those recordings, you still won't see frequencies down that low.

The only curious thing in your post now is why the crossover worked for one side and not the other. I would check the settings on the sony as well as on the ICBM. Also double check the settings on your playback device (Which is?). Just double check where all the crossovers are set. Also, turn up the volume on your sub. The information may actually be there but you might just not be hearing it.