Yes, but again I don't think the valoq was built for analog setup.
I am researching on which opamp is best to be used. So far all the metal caps cannot be used unless one is willing to take out the 8 pin DIP board and permanently install them. Also not all opamp can be fitted. Those who are mounted on a separate board do not fit, only the one without any mounting board fit.
The supplied opamp 8820 (and the one which came free, muses8920, in Japan) provide a very thick sound, bass heavy and warm. That added with already natural sounding AKM DAC do not go well. Below is a summary of various opamp I have found that should work with similar sound result performance:
source: http://www.head-fi.org/products/asus-xonar-essence-stu/reviews/9307
LPF opamp rolling (I/V: LM49720)
LM4562 – stock, again: well balanced, clean, airy and open but slightly to the warm side.
LM49720 ‘Metal Can’ – Similar to stock, slightly less dense and more open in the mid.
OPA2604 – thick and slow, grainy.
OPA2209 – Full, similar to OPA2604 but without being overly thick and slow.
OP270 – Lean, slightly lacking in bass, slightly bright.
OP275 – Well balanced, though soundstage isn’t great.
AD8066 – Very airy and open, great soundstage but a little bright.
AD8620 – Like a tuned down version of AD8066, with better body and smoother presentation.
OPA2227 – warm and slightly dull, but sparkly on the top.
OPA2134 – similar to OPA2227, more mid centric and not as sparkly.
MUSES01 – Similar to stock, but slightly better dynamic and soundstage.
MUSES8920 – somewhere between OPA2227 and OPA2134.