Weak bass problem...

[Izuall]

So i have this setup:Soundcard and active speaker system both have theyr op-amps replaced with OPA2228P on the soundcard and AD8599 on the preamp board of the speaker system(they are relatively new , about 4 months).
A couple of days ago i noticed that the bass became dry and weak(instead of rich and bloomy(as it was before),what could be the source of the problem?(faulty cap?could the opamps change characteristics so dramaticly?)

 

[AndrewT]

caps or joints to the caps.

 

[Izuall]

I tought the same..but the system is prety new and there are no visible signs..
Can EMI screw up an op-amp?(the drivers arent magneticly schielded)..how sensitive is the AD8599 to EMI?

 

[madtecchy]

Does your active speaker system have a subwoofer??

 

[Izuall]

No.It's a 2.0(speaker system)

 

[madtecchy]

Also first thing to do is see what part of the system is at fault .. do you have another source you can use to test the active speakers or another amplifier speaker system to test the sound card... Drvers are magnetically sheilded to prevent magnetic field disturbing CRT TV,S / Monitors>>

 

[Izuall]

I think the soundcard is fine.(i hear no difference in my headphones)

 

[madtecchy]

I understand the problem is with both channels.. If so the first place to look will be the part of the circuit that is common to both. Wich more than likley will be the psu. The guess of andrews could be on target.. Maybe capacitors. best thing to do is open up the unit and start investigating . Check solder joints, inspect electrolytics for signs of bulging or leakage. Check psu rail voltages , If possible with unit playing quiet and then louder to see if you have lots of psu sag.. Speculating will not help its time to get stuck in and start eliminating ...