Conversion of a Chord DAVE to DC power using two Uptone Audio JS-2s

[DAVE JS2]

1 hour ago, asdf1000 said:

It would be cruel to just ask him to measure and deny him a chance to listen 😢 

 

Hang on...what about the cruelty of depriving ME of listening to my upgraded DAVE?!

 

It is just one that Chord has bought in (see photo), and I'd imagine @JohnSwenson has more pressing matters to attend to. But I'd be happy to send it if it would be of use to him.

[skatbelt]

1 hour ago, DAVE JS2 said:

 

Hang on...what about the cruelty of depriving ME of listening to my upgraded DAVE?!

 

It is just one that Chord has bought in (see photo), and I'd imagine @JohnSwenson has more pressing matters to attend to. But I'd be happy to send it if it would be of use to him.

 

Thanks! Hmmm, there goes my assumption of purposely built or at least custom built to spec for Chord. This is an off the shelf supply. For medical, among other applications. Costs about 50 euros a piece here in the Netherlands and a lot less when bought in large batches.

 

Technical specs: https://www.xppower.com/portals/0/pdfs/SF_ECM40-100.pdf

 

 

[DAVE JS2]

2 minutes ago, skatbelt said:

Hmmm, there goes my assumption of purposely built or at least custom built to spec for Chord.

 

This Head-fi post is Rob Watts on the medical SMPS, whats important in a PSU for his DACs and the further conditioning measures he uses in the DAVE, post PSU.

 

" Would using a better SMPS give better SQ? Maybe, but the evidence suggests no. "

 

I read that piece before deciding to give the JS-2s a go, and you know my conclusion: 😳. ;)

[ecwl]

38 minutes ago, skatbelt said:

 

Thanks! Hmmm, there goes my assumption of purposely built or at least custom built to spec for Chord. This is an off the shelf supply. For medical, among other applications.

My understanding based on what was discussed in Head-Fi by Rob Watts is that he picked the “best” SMPS he thinks is appropriate for his DAC design and then design the regulators and RF filters subsequent to the SMPS around the specific SMPS. So to him, the PSU of the unit is not the $50 SMPS or whatever LPS is in use but the entire system from the SMPS + RF filters and regulators, etc. So it didn’t surprise me that the SMPS was only $50. In fact, I thought it was going to be cheaper than that.

 

[MarkusBarkus]

23 minutes ago, DAVE JS2 said:

 

I read that piece before deciding to give the JS-2s a go, and you know my conclusion: 😳. ;)

...I read that too, and everything I could get my eyes on before buying the DAVE and before making the PS conversion, and you know my conclusions: 😉

 

I guess I trust @Nenon, @ray-dude, @austinpop and a few others here more than Rob Watts for certain Chord progressions. They have different motivations and boundaries, in my estimation.

 

BTW: I offered @Nenonmy smps to test a month ago, and I could hear the laughter inherent in his polite decline of my generous offer.
 

The DAVE smps may indeed have tested well in the context of its little nest inside a CNC-ed aluminum case, but it is an ordinary component in an extraordinary product. Fun stuff, right?
 

 

[Nenon]

2 hours ago, DAVE JS2 said:

 

Hang on...what about the cruelty of depriving ME of listening to my upgraded DAVE?!

 

It is just one that Chord has bought in (see photo), and I'd imagine @JohnSwenson has more pressing matters to attend to. But I'd be happy to send it if it would be of use to him.

 

I have noticed that the older DAVE DACs use the above off-the-shelf product. The newer manufactured units I have seen, 2020 in particular, had this one - EOS Power LFWLT40-3002. It's a $15 power supply on a $10K+ DAC. No wonder we all like this upgrade :). 

 

They can talk as much as they want about voicing, but...

16 hours ago, Nenon said:

I did not like the DAVE DAC in its stock form.

 

and...

16 hours ago, Nenon said:

After replacing the stock SMPS on the DAVE and doing some more changes on my server, the DAVE completely transformed from an average DAC to exceptionally good.

 

In other words, the voicing around the $15 SMPS was not really something I liked in my system. 

[DAVE JS2]

16 minutes ago, Nenon said:

 

I have noticed that the older DAVE DACs use the above off-the-shelf product. The newer manufactured units I have seen, 2020 in particular, had this one - EOS Power LFWLT40-3002. It's a $15 power supply on a $10K+ DAC. No wonder we all like this upgrade :). 

 

They can talk as much as they want about voicing, but...

 

and...

 

In other words, the voicing around the $15 SMPS was not really something I liked in my system. 

 

Yeah...

 

Rob's Head-fi post indicates that not a great deal of thought went into the SMPS (no A/B testing, @skatbelt😱 ) despite all the downstream work he describes.

 

To paraphrase @kennyb123, best to combine the world-class elements that each of these leading individuals bring to the table and 'tune out' other elements based on our own experiences and preferences.

 

Though it would have been nice to have an external DC input, as with HMS, to allow for experimentation without voiding the warranty... 🧐

[MarkusBarkus]

I liked the OEM DAVE well enough, but with an upgraded PS, it's just flat-out better in my room. My unit is a few months old, re: ps model.

[ray-dude]

On 11/23/2020 at 1:05 PM, ray-dude said:

 

Well timed!  I actually have a loaner Sean Jacobs DC4 in house for testing/review (I've had a Sean Jacobs DC3 on my DAVE for years, and consider it one of the most impactful system upgrades I've done).  Hopefully by the end of the year I'll have a (one part ;) write up on the impact of power quality on DACs like the Chord DAVE.

 

Thank you for posting your experiences

 

 

Quick update: after a couple months of running the DC4 7/24, it was fully burned in so I was able to get to get my deep dive done over the holidays. (note to self: never sign up for a review of a component with giant Mundorf caps unless you have time/patience for a couple months of burn in)

TL;DR - It's awesome with DAVE!

Look for the multi-part (sorry, I couldn't help myself ;) review to be posted pretty soon.

[DAVE JS2]

On 1/15/2021 at 1:45 AM, ray-dude said:

 

Quick update: after a couple months of running the DC4 7/24, it was fully burned in so I was able to get to get my deep dive done over the holidays. (note to self: never sign up for a review of a component with giant Mundorf caps unless you have time/patience for a couple months of burn in)

TL;DR - It's awesome with DAVE!

Look for the multi-part (sorry, I couldn't help myself ;) review to be posted pretty soon.

 @ray-dude Fantastic, thanks for letting me / us know - I'm looking forward to setting aside the time to read it ;)

 

Don't forget to let everyone know that other LPS' are available... 

 

Quick update from my end; I have just got round to earthing all the unused inputs on my DAVE (couple of BNC's, XLR and USB) and Blu Mk II and was pleased with the improvement / effort ratio - further reduces the RF noise, a 'calmer' listen. Should have done it long ago. You guys have probably done it already, but I mention it 'just in case'.

 

Over the next few days / week I'll be DC converting the Blu Mk II, will post her about how I get on. Wish me luck!

[asdf1000]

19 minutes ago, DAVE JS2 said:

I have just got round to earthing all the unused inputs on my DAVE (couple of BNC's, XLR and USB) and Blu Mk II and was pleased with the improvement / effort ratio - further reduces the RF noise, a 'calmer' listen. Should have done it long ago. You guys have probably done it already, but I mention it 'just in case'.

I'm not question the improvement you hear but this is generally not recommended practise (earthing all inputs).

 

I don't think this would be recommended by John S or Rob Watts.

[DAVE JS2]

25 minutes ago, asdf1000 said:

I'm not question the improvement you hear but this is generally not recommended practise (earthing all inputs).

 

I don't think this would be recommended by John S or Rob Watts.

Interesting thanks - do you know what the issue might be? It seemed like a logical thing to do to me.

[asdf1000]

13 minutes ago, DAVE JS2 said:

Interesting thanks - do you know what the issue might be? It seemed like a logical thing to do to me.

 

System grounding is a really complex topic.

 

@JohnSwenson has written a lot about it on various threads.

 

This is a good place to start

 

https://www.ranecommercial.com/kb_article.php?article=2107

 

[DAVE JS2]

Just now, asdf1000 said:

 

System grounding is a really complex topic.

 

@JohnSwenson has written a lot about it on various threads.

 

This is a good place to start

 

https://www.avw.com.au/images/techpapers/Rane_note_110.pdf

 

@asdf1000 Thank you very much, I will read that.

 

For clarity; I earthed the grounds, not the signal lines (apologies for my sloppy language).

[asdf1000]

1 minute ago, DAVE JS2 said:

@asdf1000 Thank you very much, I will read that.

 

For clarity; I earthed the grounds, not the signal lines (apologies for my sloppy language).

 

All good. I don't know if that's any better though 😀

 

The main thing is it didn't get worse for you, which is the biggest danger with improper system grounding - when you start to hear audible buzz/hum.

 

And I guess it is possible that (by luck) you actually have objectively improved things too. 

 

It's such a complicated thing that the only way to get good advice on system grounding is to sketch up a full system diagram LOL. Showing how everything is connection.

 

That's a lot of work but it's really the only way an expert here (not me) could give good advice.

 

Other than that, reading the Rane article is a great place to start.

[DAVE JS2]

4 minutes ago, asdf1000 said:

 

All good. I don't know if that's any better though 😀

 

The main thing is it didn't get worse for you, which is the biggest danger with improper system grounding - when you start to hear audible buzz/hum.

 

And I guess it is possible that (by luck) you actually have objectively improved things too. 

 

It's such a complicated thing that the only way to get good advice on system grounding is to sketch up a full system diagram LOL. Showing how everything is connection.

 

That's a lot of work but it's really the only way an expert here (not me) could give good advice.

 

Other than that, reading the Rane article is a great place to start.

@asdf1000 I'm coming at it from trying to tame the RF sensitivity of the DAVE and Blu Mk II - I definitely feel like I'm on the front foot of the battle at the moment. I'll take my lucky shot!

I feel it did help me, but I will be sure to be mindful in future.

 

Thanks again for taking the time to reply and your advice, its much appreciated.

[asdf1000]

14 minutes ago, DAVE JS2 said:

@asdf1000 I'm coming at it from trying to tame the RF sensitivity of the DAVE and Blu Mk II - I definitely feel like I'm on the front foot of the battle at the moment. I'll take my lucky shot!

I feel it did help me, but I will be sure to be mindful in future

 

If you have a chance to ask Rob Watts over on Head-Fi forum, it'd be interesting to read his opinion on it !

 

I might have it completely wrong.

 

If you do end up doing that (if you can be bothered) then please share what the Guru says here !

 

 

[MarkusBarkus]

10 minutes ago, asdf1000 said:

please share what the Guru says here !

...I think a certain Guru sez: Wave ferrite-ed BNCs for ICs on that Head-Fi site, if you have RF concerns. FWIW: I use them between DAVE and MScaler. Sound good, IMO.

[ray-dude]

4 hours ago, DAVE JS2 said:

Don't forget to let everyone know that other LPS' are available... 

 

 

Most definitely!  I've done some quick tests with other supplies for the 5V rail, and the improvement over the stock SMPS is profound.  For any DAVE owner that is looking to unleash what the DAC is capable, adding a quality power supply will have a huge impact (and JS2 is definitely in that top tier of power supplies)

[Datka]

On 1/17/2021 at 7:41 AM, DAVE JS2 said:

@asdf1000 Thank you very much, I will read that.

 

For clarity; I earthed the grounds, not the signal lines (apologies for my sloppy language).

can you please post pictures how this was grounded ?

And also i have purchased dual lps from forum member here , to me after the swap it sounds so much better, much more natural sound , thinking now to upgrade to Uptone audio but they dont seem to make 15V devices only goes up to 12 i think, so how was this done?

 

I also think that need to run ground from Dave to the Ground of incoming power , if someone can send pictures how the grounding was accomplished this would be awesome but i definitely feel that upgrading power changed how Dave sounds ,, I'm planning on keeping it for another few week and going back to original to confirm what I'm hearing  

[Fourlegs]

@Datka thanks for posting your photos and diagram. Just one point for others on your labels of the various voltages on the Dave, the Ground in your diagram is not Ground but rather is 0V and if my memory serves me from when I did my Dave it is a floating voltage and is not tagged to Ground. 
 

I have earthed the chassis of my Dave to Ground but I left the 0V rail floating. 

[Datka]

8 minutes ago, Fourlegs said:

@Datka thanks for posting your photos and diagram. Just one point for others on your labels of the various voltages on the Dave, the Ground in your diagram is not Ground but rather is 0V and if my memory serves me from when I did my Dave it is a floating voltage and is not tagged to Ground. 
 

I have earthed the chassis of my Dave to Ground but I left the 0V rail floating. 

Thanks , you are correct about ground it should be 0V, actual pictures came from member here who actually did all this work and took pictures including one i uploaded, he decided to later sell this and this is how i ended up with it... 

For me even using relatively cheaper LPS like Keces ( compared to DC3, or UpTone) had pretty noticeable change in sound, i would say sound became more natural , little less digital? but cant really use this term since last time i used analog source 15 years ago,,,

Now about ground , if i understand this correctly I need to run ground wire from my power cord that is feeding dual LPS to the chassis of  Dave?  Thanks. 

[Fourlegs]

14 minutes ago, Datka said:

Thanks , you are correct about ground it should be 0V, actual pictures came from member here who actually did all this work and took pictures including one i uploaded, he decided to later sell this and this is how i ended up with it... 

For me even using relatively cheaper LPS like Keces ( compared to DC3, or UpTone) had pretty noticeable change in sound, i would say sound became more natural , little less digital? but cant really use this term since last time i used analog source 15 years ago,,,

Now about ground , if i understand this correctly I need to run ground wire from my power cord that is feeding dual LPS to the chassis of  Dave?  Thanks. 

I use a three pin GX16 connector for the  +/-15V and 0V and a GX16 two pin for the +5V 0V. I found that shielded dc cables with the shield earthed gave the best sound so I use the earthed shield to earth the Dave. The reason I use shielded dc cables is that otherwise you are just connecting a lovely RF aerial (you might call it a dc cable but what I see is an aerial) straight into the sensitive circuits of the Dave. In my experience the shield is nowhere near as effective if it isn’t earthed. 

[Datka]

ohh ok, I'm used to ground shield on the  power input side and keep shield not connected on the electronics side.

 

so in this case , shield from DC cables on one end connects to chases of the DAVE and where does it connect on the other end ? i guess I'm asking this because my LPS just has regular DC out so im trying to understand how is it getting making connection to earth :)

sorry if what I'm asking doesn't make sense, lol  , 

[Datka]

Hi , have been enjoying Chord Dave using dual kecess p3 , and as always we look for things to improve I was thinking 

1. replaced dual Kecess  P3 with dual JS2 or

2. keep keces and add ldovr for each output of kecess to make it ultra low nose , wha do you guys think 

 

I also was thinking to do mundorf dc cables using silver gold like it was recommended in forums .   
Thanks