In the datasheet for the PCM1748 it states this device offers some post DAC low pass filtering internally, but it is not enough to attenuate out of band noise (artifacts from DAC process), and the recommendation is to employ additional low pass filtering. Without looking at the SB3 schematic, or even pictures of the PCB, I assume the designer(s) carried this recommendation out by an active filter providing some gain and the filter function. Removing this op-amp as a means to higher sonic performance seems troubling to me. If the down stage components (preamp in particular) are capable of high bandwidth it is possible in some instances to create unstability in the power amp. Don't get me wrong, I like modifying stuff too, but this is something I would leave alone, as it performs a useful and necessary function. It might be interesting however to replace the bipolar stock opamp in favor of say an AD827, or many other higher performance parts.
This reminds me of the modders who remove the muting circuits in cd players...yeah those annoying clicks are real fun... I would love to hear what the SB3 engineers are saying about the dudes who reroute traces and clip this line and that and just remove parts that "seem" like they are in the way. I guess it is fun on some level (kind of like those dudes that pimp out honda civics), but you have to trust the designer on another level too! just my 2 cents. -- dpac996 ------------------------------------------------------------------------ dpac996's Profile: http://forums.slimdevices.com/member.php?userid=9407 View this thread: http://forums.slimdevices.com/showthread.php?t=19822 _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
