[flyte3333]

And i listen to a Surface pro battery power and it sounds horrible. Hmm

How so?

Just for additional info, if anyone doesn't like the sound of a laptop running on battery (disconnected from mains power) compared with other USB sources, would be great if you could describe how.

If it sounds too warm and not detailed enough?

If there are warmer sounding USB sources than a battery powered laptop, that's just as interesting. Maybe it's the USB signal integrity thing John Swenson has been harping on about for a few years now..

Personal preferences are a massive factor here but it's still interesting to read other people's observations.

 

[Rob Watts]

I can´t follow you, Rob! I first had a laptop with the DAVE because I believed you that the source didn´t matter. But every step I took from that gave an audible improvement - beginning with the MicroRendu, adding LPS 1.2, then TX-USBultra and Cybershaft clock and finally an Innuos Zenith SE. Is it just RF noise I am hearing? I was first a bit angry about myself and about Chord in the beginning that I just couldn´t get peace of mind using a laptop and leaving things there. That was the reason why I decided to buy the Dave. Just care about music and don´t need to read in forums about server-upgrades.
At the same time I think the DAVE is an incredible product and I can live with that.
But I am really surprised reading your claim that a laptop should sound better or as good as a good server with the DAVE. That is not my experience, not at all!

I guess it depends what you mean by a server sounding better; my experience is that they sound brighter, with the illusion of better transparency; classic hallmarks of RF noise generation. And the problem isn't so much Dave, but the power amp Dave is connected too being sensitive to RF. But absolutely for sure, a lap-top connected to nothing but Dave's USB port will give the lowest possible RF noise into Dave - and will not affect power amps at all.

Well i dont supose that it is a good market stratege to sell dave and apply that you need extra gear with it?

I don't care about marketing; indeed, one could argue that extra gear would create more business opportunities for Chord. I just want the best possible sound, and to do that requires understanding of the engineering issues involved. That's why the forums are so very valuable, as sensitivities and how the gear is used, gives me valuable insight - if I get to replicate the issue. Sometimes however, people just enjoy added distortion, particularly noise floor modulation....

 

[jonstatt]

I guess it depends what you mean by a server sounding better; my experience is that they sound brighter, with the illusion of better transparency; classic hallmarks of RF noise generation. And the problem isn't so much Dave, but the power amp Dave is connected too being sensitive to RF. But absolutely for sure, a lap-top connected to nothing but Dave's USB port will give the lowest possible RF noise into Dave - and will not affect power amps at all.

There has been a trend to state that the only negative influence RF or EMI can introduce is brightness. Thus the A/B comparison many of us are doing when changing cables or equipment is to find the "warmer" or "darker" version, and ruling that it must be the more correct. But I think there is another kind of "noise" that gives the impression of not just darker, but smeared, as if the low level dynamics are blurred together. This seems to be an effect others have reported too with certain USB links and influenced by a choice of USB cable even. How else can you explain the fact that the USB connected version vs TOSLINK of an identical bitstream would sound "darker"?

I feel we have over simplified the influence of noise to always be added brightness.

 

[Crgreen]

There has been a trend to state that the only negative influence RF or EMI can introduce is brightness. Thus the A/B comparison many of us are doing when changing cables or equipment is to find the "warmer" or "darker" version, and ruling that it must be the more correct. But I think there is another kind of "noise" that gives the impression of not just darker, but smeared, as if the low level dynamics are blurred together. This seems to be an effect others have reported too with certain USB links and influenced by a choice of USB cable even. How else can you explain the fact that the USB connected version vs TOSLINK of an identical bitstream would sound "darker"?

I feel we have over simplified the influence of noise to always be added brightness.

I think that’s right. There are distortions, digital and otherwise, which can make music seem darker, or even duller. On occasions, this can be welcome given that a lot of recordings are over bright, but I speak as a music listener not as an audio engineer. I imagine Rob would agree, which is why he places emphasis on depth, which is probabaly a more neutral feature for assessing accuracy.

 

[delirium]

I guess it depends what you mean by a server sounding better; my experience is that they sound brighter, with the illusion of better transparency; classic hallmarks of RF noise generation. And the problem isn't so much Dave, but the power amp Dave is connected too being sensitive to RF. But absolutely for sure, a lap-top connected to nothing but Dave's USB port will give the lowest possible RF noise into Dave - and will not affect power amps at all.



I don't care about marketing; indeed, one could argue that extra gear would create more business opportunities for Chord. I just want the best possible sound, and to do that requires understanding of the engineering issues involved. That's why the forums are so very valuable, as sensitivities and how the gear is used, gives me valuable insight - if I get to replicate the issue. Sometimes however, people just enjoy added distortion, particularly noise floor modulation....

Hi Rob! After fidelizer has calmed down my laptop a bit and utopia or the cable has settled? I tried usb on battery only, and without isoregen and lps1. And you are right sir!!! Much better? But optical dident work for me for some reason? And i thank you for saving me the money for a streamer...bye the way...dave is great

 

[flyte3333]

I tried usb on battery only, and without isoregen and lps1. And you are right sir!!!

Perfectly aligned with my own observations - as great as the Uptone LPS-1 and ISO REGEN are, there is still some coupling to mains power and I can hear that it's slightly brighter than TOSlink. When I take my microRendu (all these devices mentioned are designed by John Swenson) off the grid and power it by battery and optically isolate ethernet (battery power the FMC's also), it goes to another level in performance - as warm as TOSlink but with the feel good factor of having the master clock controlling the timing.

That's for weekend listening because it's a pain in the a$$ to setup.

My daily source is TOSlink and sound fantastic.

 

[yakaway]

Try this
https://www.psaudio.com/directstream-p20-power-plant/

 

[Triode User]

Try this
https://www.psaudio.com/directstream-p20-power-plant/

Regarding that I have mentioned before that I used to own a PSAudio P10 but it injected more RF/EMI noise into the supply than came out of the wall socket (measured by a meter).

On the general issue I think part of the problem with this whole discussion regarding usb/optical/RF noise/ etc is that we are relying on peoples reported assessment of what they find ‘better’. I am sure that these are all reported with the best intentions but as we well know, one mans better can be another persons worse. Hence why I apply a certain amount of salt (or YMMV) to various pronouncements.

For me, I find that long term listening fatigue is a good indication that all is not well. Certainly this often overturns my initial assessment of what I think is better or worse. After fiddling with and without ferrites on my usb from Zenith SE to Blu2 or to Dave direct I have reverted to ferrite free usb. The cable is Supra usb. Nothing special but not cheap and nasty.

At the end I guess all each of us can do is fiddle until we get the sound we like.

 

[yakaway]

They are not the same

 

[Triode User]

They are not the same

Of course they are not but if the P10 had issues it means that we should not always believe what we are told. Big, shiny and expensive is not always better.

 

[Rob Watts]

There has been a trend to state that the only negative influence RF or EMI can introduce is brightness. Thus the A/B comparison many of us are doing when changing cables or equipment is to find the "warmer" or "darker" version, and ruling that it must be the more correct. But I think there is another kind of "noise" that gives the impression of not just darker, but smeared, as if the low level dynamics are blurred together. This seems to be an effect others have reported too with certain USB links and influenced by a choice of USB cable even. How else can you explain the fact that the USB connected version vs TOSLINK of an identical bitstream would sound "darker"?

I feel we have over simplified the influence of noise to always be added brightness.

If you are talking about analogue cables or other analogue gear I would absolutely agree, as there are a myriad of other factors that can influence the sound. But what we are talking about here is the very specific instance of bit perfect data being delivered to one of my DAC's via USB - and here there is only one mechanism that can possibly alter the sound - and that is RF noise injected into Dave and the rest of one's system. Jitter has absolutely no measured or subjective influence on my DAC's; it's bit perfect data, so the data has no consequence; the only thing that can possibly modify SQ is RF noise, which for sure changes the SQ (I have measured it many times and correlated it to SQ) by generating noise floor modulation. And increased noise floor modulation sounds brighter, and can easily be confused with improved transparency.

 

[delirium]

Regarding that I have mentioned before that I used to own a PSAudio P10 but it injected more RF/EMI noise into the supply than came out of the wall socket (measured by a meter).

On the general issue I think part of the problem with this whole discussion regarding usb/optical/RF noise/ etc is that we are relying on peoples reported assessment of what they find ‘better’. I am sure that these are all reported with the best intentions but as we well know, one mans better can be another persons worse. Hence why I apply a certain amount of salt (or YMMV) to various pronouncements.

For me, I find that long term listening fatigue is a good indication that all is not well. Certainly this often overturns my initial assessment of what I think is better or worse. After fiddling with and without ferrites on my usb from Zenith SE to Blu2 or to Dave direct I have reverted to ferrite free usb. The cable is Supra usb. Nothing special but not cheap and nasty.

At the end I guess all each of us can do is fiddle until we get the sound we like.

You will come a long way with a dedicated mains powerline.....

 

[elviscaprice]

Besides RF noise, once that is eliminated, kept at bay, isolation, I think it's all about clocking. I look forward to John Swenson building his own instruments to study this issue and measure why external clocking can effect a bit perfect data stream and is cumulative from one component to another, regardless of reclocking. Very difficult to correct. Is it phase noise? This difference in external server/component clocking can be heard in DAVE's direct output to speakers/headphones and not attributed to RF noise differences.

 

[Rob Watts]

With USB the source clock is completely irrelevant - clocking comes from the FPGA only as it is isochronous asynchronous USB. And the data crossing the galvanic isolation interface is clocked only from the FPGA clock.

 

[ray-dude]

You will come a long way with a dedicated mains powerline.....

+1

A dedicated 30A line with 10-2 Romex really cleaned up a lot of variability and randomness I was hearing (much more relaxed listening experience).

Extremely cost effective and a fantastic baseline for anything else you're tweaking.