[xLeira]

Hi, I'm stuck on a problem here. I've searched lots of forums and haven't found similar problems but I think this is a setup issue and I do not have the knowledge to fix this on my own so I need help from you guys.
 
Setup:
 
Xonar DS > Marantz MR215 > Infinity 902-6794 A9226 sub-woofer > JVC SP-MXJ77 x2
                                       > Headphones
or
Xonar DS > Marantz MR215 > Infinity 902-6794 A9226 sub-woofer                                      
                                       > JVC SP-MXJ77 x2
                                       > Headphones
 
So the JVC's has been releasing high-pitched noise whenever the bass are emphasized. It's hard to explain but the twitters gives you a sound that feels like a "slap in your face" and is continuous. That is when the bass are emphasized though, one example would be in the movies whenever a drum roll happens. Another would be in a song with emphasized bass.
 
Now, I've tested my speakers in a different setup and is functioning well even in higher volumes. Another thing I noticed is that this problem only occurs when the sub-woofer is connected, otherwise, the JVC's are not emitting those noises. These gave me the impression that it might be an impedance problem. I've read a few things about driving different impedance but I really cannot understand it(please excuse my stupidity).
 
JVC specs:
120 watts
6 ohms
 
Marantz specs:
http://www.vintage-audio.com.ua/en/cat/334/1597.html?begin=11
 
and I can't find specs on the woofers. If it is this kind of problem, is there any way I can fix this? Hoping for your replies, I'll really appreciate it. 

Thanks!

 

[NA Blur]

It could be a couple of things.
 
A few questions first:
 
1.)  Is the subwoofer wireless?
 
2.)  Does the problem go away if you move the sub further aware from the amp?
 
3.)  How high is the subwoofer volume knob turned up when the problem occurs?
 
4.)  Can you use your iPod or other device like a CD player to test the same setup bypassing the Xonar?  For example take your iPod or computer and run the stereo jack out into the aux in on the Marantz.  If the problem goes away then it is most likely the Xonar.
 
5.)  Does the Marantz have a bass boost function?  Is it turned on?  Perhaps it is distorting the low end.
 
6.)  Does your subwoofer have a selectable dial for frequency say from 5Hz to 250Hz?  If so turn it to about 90Hz and try again.
 
7.)  Does the problem go away if you turn the volume out of the Xonar up to 90%?
 
To me it sounds like the pre-amp side on your Marantz MR215 feeding the subwoofer is going bad.  I had a similar issue on the phono stage of an amplifier, but it was more of a constant squeel sound.

 

[xLeira]

Quote:

It could be a couple of things.
 
A few questions first:
 
1.)  Is the subwoofer wireless?
 
2.)  Does the problem go away if you move the sub further aware from the amp?
 
3.)  How high is the subwoofer volume knob turned up when the problem occurs?
 
4.)  Can you use your iPod or other device like a CD player to test the same setup bypassing the Xonar?  For example take your iPod or computer and run the stereo jack out into the aux in on the Marantz.  If the problem goes away then it is most likely the Xonar.
 
5.)  Does the Marantz have a bass boost function?  Is it turned on?  Perhaps it is distorting the low end.
 
6.)  Does your subwoofer have a selectable dial for frequency say from 5Hz to 250Hz?  If so turn it to about 90Hz and try again.
 
7.)  Does the problem go away if you turn the volume out of the Xonar up to 90%?
 
To me it sounds like the pre-amp side on your Marantz MR215 feeding the subwoofer is going bad.  I had a similar issue on the phono stage of an amplifier, but it was more of a constant squeel sound.

 
1.) No it isn't.
 
2.) About 1 meter away from the amp, I'll try finding a longer cable and test it again.
 
3.) My subwoofers doesn't have any kind of knobs, it only has audio in L/R and audio out L/R. In the Marantz, the problem pops up when the volume is -30 dB while playing Bass Mekanik - Maximum Boom.
 
4.) Tried that, the problem still exist. 

 I thought this was the fix. The problem did not show up when I increased the volume up tp -30 dB, but it occured around -24 dB.
 
5.) It has Loudness and Low Filter(don't know that this button do), tried turning off/on the loudness button and the problem still exist.
 
6.) No dials.
 
7.) Nope.
 
My friend told me that the cause might be the Marantz. It seems too old and kinda dirty. I'll try cleaning it myself but if the problem still persist, I'll find a technician for this problem. Another thing I noticed is it occurs even in my headphones, when it is connected. Might really be the Marantz.

By the way, thanks for replying and the nice way of troubleshooting.