Musical Fidelity V-DAC2 - opamp comaptibility

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Congratulations! You picked other components but I am sure it has improved. If it works, it works ;)

About the tantalums, the reason I am not friend of these are:

1. unreliable over a long period of time, an experience I have made when restoring classic HiFi components.

2. high Dielectric Absoption, may not be too much of an issue when using these as bypass for supply. Would be bad for analog signal path.

But tantalums have advantages like good HF capabilities which makes the these a good choice for digital supply bypass.

- Johannes
 
I believe that the first upgrade to do on V-DACII is to properly resolder all components. I don't know if this is due to lead-free technique or to poor manufacturing, but soldering is so brittle and weak that most of the electrolytics have come off really easily as I wiggled them, including legs, leaving moulded footprints on pads. There must be some contact resistances all over the place there.
 
I thought of it as normal for SMD electrolytics. The internal contacts to the aluminum foil seem to come off easily once you wiggle and pull the capacitor off. At least most of the time. The plastic ground plate and contacts remain firmly soldered to the pad but sometimes even these can be pulled off, one by one, without applying heat.

For modders, this is a fortunate way around having to use specialized SMD tools to remove electrolytics.
 
Found this thread, very nice mods here! Felt an urge for modding my v-dac ii and ordered Wima MKS for c40/c57 and c3/c103, like poetry2me in #31. I thought about changing the electrolytic capacitors too. It seems like the values are 16V/100uf an 16V/10uf and 16V/470uf? If anyone have experience of changing caps in v-dac ii, I would really appreciate comments and recommendations.
thanks!
 
Investigated about power supply of thé i/v stage and power supply rails for op amps are long.
So added 4.7uF mlcc 35V capacitors near power supply of each opamp. Also added a electrolytic capacitor 100uF.
Since my preamp already removes DC from input signal, I just bypassed output electrolytic capacitors.

Nb: The vdac uses switching capacitor voltage convertor to provide positive and négative rails for thé i/v stage. No regulators except RC filters far from thé i/v stage opamps. I doubt that replacing thé stock regulators will affect a lot sound quality
 

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