I think you have some DC coming out of your preamp. You might try measuring the preamp output with voltmeter. It's not good for the amp or the speakers.
Pass X150 is producing "Pop" during power-down
Hello all,
I have been experiencing a thump or "pop" from my recently purchased X150 (5yr old) when I power down the amp using the front button. The previous owner didn't experience this. I am using the single-ended RCA input from my receiver for now. Also, I notice all the woofers of the speakers retract (ie get sucked in or move backward) upon the power on and stay retracted until I power it down which gives the thump or pop .
If I physically disconnected the preamp from the amp, I get the "pop" not only during power-down but also during power-on.
Interestingly, the turn off thump and woofer retraction phenomenon disappear totally if I remove the XLR pin1 to pin3 jumper to pretend having balanced input without physically having XLR cable plugged it. (For those who doesn't own this amp, there is a jumper connecting pin1 to pin3 of the XLR input if you are using single-ended input).
Pls excuse my long description. My questions are 1) Are these normal things to expect if I am using single-ended input? I am worried since the bass response seems compromised.
Thanks in advance for your kind input.
Kelvin
I have been experiencing a thump or "pop" from my recently purchased X150 (5yr old) when I power down the amp using the front button. The previous owner didn't experience this. I am using the single-ended RCA input from my receiver for now. Also, I notice all the woofers of the speakers retract (ie get sucked in or move backward) upon the power on and stay retracted until I power it down which gives the thump or pop .
If I physically disconnected the preamp from the amp, I get the "pop" not only during power-down but also during power-on.
Interestingly, the turn off thump and woofer retraction phenomenon disappear totally if I remove the XLR pin1 to pin3 jumper to pretend having balanced input without physically having XLR cable plugged it. (For those who doesn't own this amp, there is a jumper connecting pin1 to pin3 of the XLR input if you are using single-ended input).
Pls excuse my long description. My questions are 1) Are these normal things to expect if I am using single-ended input? I am worried since the bass response seems compromised.
Thanks in advance for your kind input.
Kelvin