I need some help troubleshooting a Sony D515. The unit has 3 levels of Dynamic Bass Boost, but they are pretty much unnoticeable. The bass boost effect applies for both the headphone and line out, but both of them sound seem to have the same issue. Comparing the sound with DBB Off and DBB at the maximum setting makes a very little change in the bass, but that's it. I have checked the usual suspects and perform the required maintenance: The output capacitors are replaced (some of the few electrolitics on this model) I also checked for damaged or beocken ground lines in the headphone connector. Everything looks ok. All SMD electrolitics are replaced. Thru-hole electrolitics I have not replacedy but they all seem fine The DBB in the D515 is digital. It has a dedicated chip right before the DAC. Hence I do not know if the bass effect is really subtle by design, or if the bass is missing. Comparing the D515 with my D777 makes the D515 sound empty (but to be fair, the D777 has a relatively punchy bass on the lowest DBB setting). To any D515 users out there or anybody with knowledge on the matter, any help is appreciated.
Interesting problem. I would suspect Master Kaosun is one of the few who would understand this problem and solve it in a flash. Posting this question on his forum could yield an insight for free.
I also took the time to re-flow the headphone connector pins, and disassembled the volume potentiometer to clean it completely. It made no difference. I'll take your advice and ask Master Kaosun.
