i have a yamaha rx 475 reciever and accusound 6.6xd speakers (5.1 set up) but the sub setting is wrong.i have it set on front speakers small,rear speakers small and cross over at 100 but the sub setting isnt right i can tell from the sound,also have bass boost at -5db. any idea what im doing wrong or what settings should be i noticed cross over at below 40 doesnt seem to put out any sound, also get a lot of feedback from sub if reciever turned off.
First of all you should have all of your speaker settings on the RX-V475 set to LARGE not small with those speakers as you want full sound environment reproduction which they can most certainly handle. Next you do not want -5dB setting but if there is a +5dB boost use that. Also your PRE SUB out should be set to 120Hz in order to get the full 20Hz-120Hz sound environment and your sub's amp should be set to the same range. Also there might/should be a setting for SWFR-F/R or L/R depending in the advanced settings of the receiver that controls the PRE-OUT level, it should be scaled 0 to +10, -10 to 0, or -10 to +10 depending on your receiver. Set this to the max output, in the first and third cases it would be +10 or in the second case it would be 0. I wish I could tell you exactly for your receiver but I haven't played with that one and I typically use high-end Yammies only. If you are talking about having your sub only put out 40Hz and below you are not going to reproduce much sound and will only hear the speaker occasionally or not at all depending on the movie you are watching or the music you are listening to. As to the sub and noise when it is off. That almost sounds like you are not plugged into the Sub Pre Out RCA connection on the back of your V475 but it could be that your receiver and the sub amp are not plugged into the same ground plane. In that case make sure everything is plugged into the same outlet. You should not have 60Hz hum with the receiver turned off from your sub if it is correctly connected. I'm somewhat shooting in the dark here as you haven't gave us enough information as to exactly what you are doing and exactly how you have you inter-connects done and your receivers DSP fully setup. Yamaha's typically have many settings you need to have correct for proper operation, as Pioneer, Sony, & even Dennon have.
