[spore]

I am not able to find a better direct replacement ic for 7660S and I replaced the following caps at location C53, C34 C44, C21, C39 and C5. They were replaced with same rating of 100uF@16V and choosen as they are somehow linked to the 7660 voltage converter chips. The caps were bought from a local electronics store who recommend me the caps saying they are good for use in power supply. I am not sure what brand they are.

The sound after modification is smooth and fluid with a nice midrange. The mid range has just the right tone, not sounding cold like previously or too warmth like the first time I am using v-dac. Bass has improved with no booming at all and bass is deep and tight.

On first listen, I still prefer the sound before modification as it is more dynamic and clean . All my cds sound good although it can be neutral and cold. However for vocals and instruments, I prefer the sound after modification as it is smooth, fluid with a nice midrange. Vocals have just the right warmth and do not sound too cold or too warmth. Not all cds sound good on the v-dac anymore. some sound better and some worse.

In addition, I need to turn up my preamp volume to listen at the same sound level as before. Guess I will stick with this configuration and hope the sound get better after burn in. I think this sound is a more accurate presentation of instruments and vocals. However, your mileage may vary

 

[josep]

Good info Spore. I have to get the time to look closely at the 7660 pdf to see exactly what to deal however, then I will get my hands around them.

I am seeing however a (nice) pair of Nichicons on place of the original output caps... and not remember you saying anything about them

Sometimes the NP (non polar) caps used by Michelson&Co (MF) in this place on his products are not as bad as they may look, it must be said.

Funny, this V-DAC, uh?

)

 

[spore]

Hi Josep, I did mentioned about changing the caps at C3 and C4 previously and you replied my threads also

This is my first dac and my first time modding. It has also been a satisfying experience seeing how the mods have improved the original sound of the v-dac for only ~15% of the cost of v-dac. Sometimes I wonder if it is due to cost reasons that average caps using Jamicon are used throughout the v-dac. On the bright side, we can easily improve the v-dac sound by just replacing to better caps.

I have complied my list of modifications (giving Joseph due credits for his hints and tips in the first place) for my v-dac. IMHO, all the modifications have improved the sound of the v-dac but your mileage may varies.

I hope that there will be more modders sharing their experience as I am just a beginner and still learning. Cheers!

List of Modifications:
1. Replace caps at location C25, C22, C45 and C61
2. Change dual op amp NE5532 at location IC7
3. Replace caps at location C3 and C4
4. Change quad op amp at location IC5
5. Replace caps at location C53, C34 C44, C21, C39 and C5

 

[T_K]

Sadly I'm quick to do the mods (they take little time anyway) but then have no time to actually listen to it

So far I've done 1, 2 and 4 on spore's list and I believe the sound is now more precise with better separation and details. It's definitely better for the kind of music I generally listen to, so I'm happy.

 

[dukja]

Dear moders:

While you work on the V-DAC, can you tell if V-DAC convert the USB signal directly to I2S or indirectly through SPDIF and then I2S?

I have tried a SIIG soundcard with coax to V-DAC comparing to USB to V-DAC. Some quick test shows that coax has larger soundstage than USB input.

I am considering getting another soundcard with coax or trends UD10 or Pop Pulse for this reason.

Thanks!

 

[MatsudaMan]

Just hooked the v-dac to my ps3 via optical digital out - everything from Blu-ray, games, to music sounds SO much better. I used to think that all my mp3's stored on the hd were junk -the quality of the ps3's internal dac leaves much to be desired, but now I'm having a great time going through my collection and just using the Ps3 as transport. Anyone with a PS3 and the vdac should try this. I was just listening to a Bluray Opera (Marriage of Figaro) and the sound quality is really quite impressive through the vdac.

BTW, I'm using it in my second system: NAD c352 integrated with Wharfedale Diamond 9.5s, monitoring with Sennheiser hd580s

 

[spore]

Dujka,

USB goes to PCM2706 IC. Looking at the spec sheet, i think it goes to SPDIF 1st but I could be wrong as I did not have time to open it up to check again.

Matsuda Man,

I thought you said the sound became worse after the cap change? What happened for it to be better again?

My updated list of Modifications:
1. Replace caps at location C25, C22, C45 and C61
2. Change dual op amp NE5532 at location IC7
3. Replace caps at location C3 and C4
4. Change quad op amp at location IC5
5. Replace caps at location C53, C34 C44, C21, C39 and C5
6. Change C52, C36 and C14 from 10uf to 100uf
7. Replace caps at location C20, C43, C37, C38, C30 and C32.

After 6 and 7, sound of the v-dac is fluid and dynamic, improved imaging with wider and deeper soundstage. Vocals and instruments sound more airy. Musical overall sounds very balanced, smooth with no harshness. Just my humble observations and remember your mileage may vary.

Take note that my modded v-dac is running pretty hot compared to when I got it the first time. Well so far nothing is burnt and v-dac is still working good. I am not so concerned about the v-dac getting hotter as my power amp is much hotter than v-dac!

I will be going to vacation and not able to log in for the next few weeks...

 

[dukja]

Spore: Thanks for the reply and have a great vacation.

Quote:

Originally Posted by spore /img/forum/go_quote.gif Dujka, USB goes to PCM2706 IC. Looking at the spec sheet, i think it goes to SPDIF 1st but I could be wrong as I did not have time to open it up to check again.

 

[MatsudaMan]

Quote:

Originally Posted by MatsudaMan /img/forum/go_quote.gif Just hooked the v-dac to my ps3 via optical digital out - everything from Blu-ray, games, to music sounds SO much better. I used to think that all my mp3's stored on the hd were junk -the quality of the ps3's internal dac leaves much to be desired, but now I'm having a great time going through my collection and just using the Ps3 as transport. Anyone with a PS3 and the vdac should try this. I was just listening to a Bluray Opera (Marriage of Figaro) and the sound quality is really quite impressive through the vdac. BTW, I'm using it in my second system: NAD c352 integrated with Wharfedale Diamond 9.5s, monitoring with Sennheiser hd580s

Anyone else think that this thread has turned into a modding thread, to the point of driving out those who want to actually talk about the dac's sonic attributes and such? Maybe we should make a separate modding thread and appreciation thread.......

 

[dukja]

Quote:

Originally Posted by MatsudaMan /img/forum/go_quote.gif Anyone else think that this thread has turned into a modding thread, to the point of driving out those who want to actually talk about the dac's sonic attributes and such? Maybe we should make a separate modding thread and appreciation thread.......

Totally agree! While it is great to have those capable explore the upgrades for us. I do wish there is more appreciation/comparison/sonic-difference-with-inputs-gears discussion. Sometimes I feel V-DAC user community is very quiet. Maybe everybody have been so emerged in music....

 

[MatsudaMan]

Quote:

Originally Posted by dukja /img/forum/go_quote.gif I do wish there is more appreciation/comparison/sonic-difference-with-inputs-gears discussion.

That's exactly what this thread used to be like before all the modders came in and high jacked it.

 

[Calvin&Hobbes]

Quote:

Originally Posted by MatsudaMan /img/forum/go_quote.gif That's exactly what this thread used to be like before all the modders came in and high jacked it.

At least I became silent for these two reasons:
(1) after my PSU upgrade I am very pleased with the SQ that the V-DAC delivers in my set-up. So much musicical return on investment!
(2) I am not a modder myself and would only consider to have things done by someone else if each modification is accompanied by SQ evaluation.
Wondering: is it necessarily so that replacing parts by more expensive ones is audible? What about optimisation and synergy in the original lay-out? I would hope and think that the MF engineers have given this a good thought.. Looking at the current list of mods I wonder if any part original is left

. As much as I appreciate the enthousiasm and technical skills of the modders I believe to know that modding in itself is already lots of fun for those peoples

.
Given these reservations, I will only consider to have some essential parts modded if another left-handed person who was very appreciative of the original V_DAC (Matsudaman?

would recommend this highly. Otherwise I will happily live on with my V-DAC / PSU upgrade combo.
BTW: I use expensive cabling into and from the V_DAC: delivers perfect neutrality and transparancy.

 

[koto-in]

Quote:

Originally Posted by Calvin&Hobbes /img/forum/go_quote.gif What about optimisation and synergy in the original lay-out? I would hope and think that the MF engineers have given this a good thought.

There are those who see a recipe as the optimal result of a long process of experimentation and development that has considered all the relevant factors, and those who see a recipe as the beginning of an open process of experimentation and development where the determining factors are yet to be defined.

 

[ADD]

Quote:

Originally Posted by dukja /img/forum/go_quote.gif Maybe everybody have been so emerged in music....

Yes, well exactly

I mean, when your digital stuff now is as enjoyable as vinyl used to be, one would rather listen than post...

Anyway, I sort of agree about having seperate modding thread. Reason being mainly that people might read this thread and somehow feel the stock V-DAC is inadequate, since the whole world seems to be wanting to pull it apart and desolder everything.

Truth of the matter is that apart from the external wall wart, nothing on this thing really needs to be changed for the product to remain extremely competitive with pretty much any DAC in existence that is reasonably priced.

Think of V-DAC modding as a Generation Y'er with a back the front baseball cap who just can't stop tinkering with his Mitsubishi Lancer

 

[josep]

Hi,
I was one of the earlier 'modders' and frankly do not see the need to go much further

.

The V-DAC is a very nice unit: all Musical Fidelity CD players and DACs use since some time/models ago this basic same configuration, so with the low cost of a V-DAC you basically got the same digital chips (sample-rate converter for upsampling and the dac itself) as the much more expensive MF offers (even up to KW status), just in a smaller 'no fashion' box and cheaper sellection of components, as well as a much simplified PSU.

By trashing the supplied wallwart for any decent 12V DC PSU, you have a good improvement.
If opening boxes and soldering does not affraid (or, au contraire, seduces you as it does to me), then some cap replacing and maybe opamp too, gives good results for cents.
And is fun.
And that's it.
One may go even further, using a complete redone bipolar external PSU, transformer IV, etc, but if one wants to keep the practical size of this unit, well it is really enjoyable as it is.

I'll just advice on another wallwart/psu as the original is really too crappy (and heats the unit more than I would like ot mine). And enjoy your music with it!

Regards