Sony D515 DBB Not working?

m_saborio

Hello Mr. Kaosun

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 on this model applies for both the headphone and line out, but in both cases the bass boost effect does not seem to work. The same applies for the DDS. Comparing the sound with DBB Off and DBB at the maximum setting makes a very very small change in the bass, almost unnoticeable. I have checked the usual root causes and performed the required repairs:

• The output capacitors are replaced (some of the few electrolitics on this model)
• I also checked for damaged or brocken ground lines in the headphone connector. Everything looks ok. I still reflowed the connections
• I disassembled the volume potentiometer and cleaned it througly.
• All other SMD electrolitics are replaced (only one, appart from the output capacitors). Thru-hole electrolitics I have not replaced but they all seem fine. Plus, none of them seems to be related to the sound processing.
  

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 something isn't working as expected.

I also compared the D515 with my D777 and my SL-XP5 (same tracks, same headphones). The D515 sounds bassless when compared to the D777 (but to be fair, the D777 has a relatively punchy bass on the lowest DBB setting), and the D515 has barely more bass than my SL-XP5.


Hence, I do not know if the D515 is indeed defective, or if it is supposed to sound like that. Appart from the bass, the sound quality is really nice and enjoyable. I have not noticed any other artifacts in terms of sound quality.

Any idea and/or suggestions are deeply appreciated.

DJay

I had the same impression when I first listened to my D515. I'm afraid that's just the way it is, if you compared it to e.g. D90, D99 or later models like D32/33/34/36 you would get the impression that it has no bass at all. ;-)
I used 2x330UF in the amplifier circuit, but it didn't help. ;-)

kaosun

Maybe you can try another earphone with good bass performance, BTW don't forget the foam cover of the earbuds.

m_saborio

Good day Mr. Kaosun, good day DJay

Thank you both very much for the feedback.

@ Mr. Kaosun: I am using Beryerdynamic DT770 pro 32Ohm. They have a healthy amount of bass, and the low impedance makes them easy to drive. I might try other headphones, although I do not believe that will make much of a difference.

@ DJay: I also have a D99, and it has an ungodly amount of bass (too much for my taste TBH). It simply blows the D515 out of the water, but then again, the D99 has too much bass. I suspected already that the D515 simply sounds like that, but needed a confirmation from someone else with the same device.

Thank you both for your help!

kaosun

You can send it with your earphone to me if you prefer.