Review and Measurements of Chromecast Audio Digital Output

[Julf]

CCA is very sensitive to the quality of the USB Charger ; ie the lowest the dynamic impedance, the better the sound

Any evidence for that claim? What parameters of the sound are affected?

 

[BillG]

Any evidence for that claim? What parameters of the sound are affected?

I've a bit of anecdotal evidence, I heard it. With some phone charger I had laying around, the analog output of the CCA was full of EMI - high pitched buzzing and whirring typical of a personal computer. Once I switched back its original charger, the noise went away.

 

[Julf]

I've a bit of anecdotal evidence, I heard it. With some phone charger I had laying around, the analog output of the CCA was full of EMI - high pitched buzzing and whirring typical of a personal computer. Once I switched back its original charger, the noise went away.

Fair enough - so one really bad phone charger caused an audible buzz. That doesn't in any way imply what @tades claimed, namely that "CCA is very sensitive to the quality of the USB Charger ; ie the lowest the dynamic impedance, the better the sound".

 

[Willem]

Indeed, and we are talking about the digital output as well. My CCA is connected by wifi and powered by the supplied charger and happily sits next to a big Quad 606-2 power amplifier and quite a lot of mains wiring. There is nothing wrong with the sound (RME ADI-2 DAC and Quad 2805 electrostats, just to mention some potentially relevant components).

 

[BDWoody]

Indeed, and we are talking about the digital output as well. My CCA is connected by wifi and powered by the supplied charger and happily sits next to a big Quad 606-2 power amplifier and quite a lot of mains wiring. There is nothing wrong with the sound (RME ADI-2 DAC and Quad 2805 electrostats, just to mention some potentially relevant components).

Same result for the bunch I've got around... About half are plugged into their original charger, the other half into whatever is handy...and often stashed away among power and speaker cables. I have never noticed an issue.

 

[Shoaibexpert]

Hello
CCA is very sensitive to the quality of the USB Charger ; ie the lowest the dynamic impedance, the better the sound:
You can try this one 5V 4A and quite cheap because for Raspberry PC :
https://www.amazon.fr/gp/product/B07HF7LSXD/ref=ox_sc_saved_title_2?smid=A2Z54WBF904K0X&psc=1

BR Tades

Would you say linear PSU like say P50 is better then?

 

[Willem]

Don't worry. The myth of the superiority of linear power supplies is indeed a myth. Remember: we are dealing with a digital signal. As Archimago's test showed, the only weakness of the digital output of the CCA was a relatively high level of jitter, particularly at 24/96. Use a decent DAC and this will be cured.

 

[Julf]

Would you say linear PSU like say P50 is better then?

You seem to be a somewhat selective reader. A large number of people with extensive knowledge and expertise state that it doesn't make a difference, while one person throws in some claim that is totally unsupported by evidence... Which one do you believe?

 

[Shoaibexpert]

You seem to be a somewhat selective reader. A large number of people with extensive knowledge and expertise state that it doesn't make a difference, while one person throws in some claim that is totally unsupported by evidence... Which one do you believe?

Can't say I disagree to your observation

I was just thinking of improving that last 5% of my setup as I feel it's already at where I want it to be. I've read many subjective reddits where people claim that they 'clearly' discern differences between CCA and say Node 2i or CXNV2 optical outs to their DACs and while it makes no technical sense as it's the same bytes that are being transferred to DAC - digitally and bit perfect, I kinda wanted to see if it's say the better power supply that makes things better for those other streamers....maybe lesser jitter...though at the risk of answering my own question, I believe the M500 DAC would be correcting those jitter problems as observed by Archimago and Amir in their tests...at least I assume it does....

 

[Julf]

I was just thinking of improving that last 5% of my setup as I feel it's already at where I want it to be. I've read many subjective reddits where people claim that they 'clearly' discern differences between CCA and say Node 2i or CXNV2 optical outs to their DACs and while it makes no technical sense as it's the same bytes that are being transferred to DAC - digitally and bit perfect, I kinda wanted to see if it's say the better power supply that makes things better for those other streamers....maybe lesser jitter...though at the risk of answering my own question, I believe the M500 DAC would be correcting those jitter problems as observed by Archimago and Amir in their tests...at least I assume it does....

Fair enough - just wish the people who make the subjective claims would occasionally bother to do a proper double blind test...

 

[BDWoody]

Fair enough - just wish the people who make the subjective claims would occasionally bother to do a proper double blind test...

Well, then they wouldn't have much to 'contribute,' would they?

Would be a lot of:
"I thought I heard a difference, so clearly needed to set up some controls to be sure I wasn't fooling myself. Crazy thing...the differences disappeared. Glad I bothered, or I would have wasted that money!"

That would probably get them kicked out of the club...

 

[Shoaibexpert]

Fair enough - just wish the people who make the subjective claims would occasionally bother to do a proper double blind test...

You're right! Since CCA optical is as clean as any other thousand dollar streamer via optical...which is also what Amir's tests confirmed...I honestly do not understand why people spend 10-100 times more on stuff (setting aside features off course, which btw CCA doesn't really lack!).

There is an option in CCA to EQ Bass and Treble...to run my HD800S I sometimes feel I need a bit of Bass. Would Turning Bass up a notch via Google home app have any effect on SQ? Also, do you think the M500 DAC would be doing at least the same level of jitter correction as the D50 did on Amir's tests...and is it the same as Signal reclocking?

 

[Julf]

There is an option in CCA to EQ Bass and Treble...to run my HD800S I sometimes feel I need a bit of Bass. Would Turning Bass up a notch via Google home app have any effect on SQ?

Well, it would change the frequency response...

lso, do you think the M500 DAC would be doing at least the same level of jitter correction as the D50 did on Amir's tests...and is it the same as Signal reclocking?

It should - it is all done in the ES9038 chip.

 

[Shoaibexpert]

Well, it would change the frequency response...



It should - it is all done in the ES9038 chip.

Thanks @Julf appreciate it mate!

 

[Shoaibexpert]

I guess then this is it: Here is probably the best, cleanest, most economical (subjective) HiFi setup one can have right now - per my info: Get a CCA ($35-50) + a Mini Toslink cable ($7) + Topping E30 (SNR 113 by Amir) + Schiit Heresy ($99) = ~ $270 (all in - add any headphone of choice...the Heresy runs them all!) and call it a day! No dedicated PC, No premium USBs, No expensive XLR cables, No expensive balanced headphone cables...no BS!

Hoping this will help someone starting this journey...

 

[BDWoody]

Would Turning Bass up a notch via Google home app have any effect on SQ? Also, do you think the M500 would be doing at least the same level of jitter correction as the D50 did on Amir's tests..

I have a CCA going into an M500, and haven't had any issues. I hadn't messed with the tone controls before, but after playing with them just now for a few minutes, and other than the obvious frequency changes I didn't notice any obvious distortion or degradation as I moved the sliders around. Was casting from Tidal and Qobuz.

 

[tades]

Any evidence for that claim? What parameters of the sound are affected?

Hello. Back to your question : with kind of supply I mentioned but lower dynamic impedance, the optical stream is cleaner, less polluted, so giving more robust bass, and less undesired treble interference. Make the test, before claiming a bit is a bit: It's a <15€ experience. Once you made your own , I'm interested to get your technical comments and explanation

 

[Julf]

Hello. Back to your question : with kind of supply I mentioned but lower dynamic impedance, the optical stream is cleaner, less polluted, so giving more robust bass, and less undesired treble interference. Make the test, before claiming a bit is a bit: It's a <15€ experience. Once you made your own , I'm interested to get your technical comments and explanation

So did you actually make a test? As in a proper, level-matched, double-blind one? Make the test, before making *any* claims. Once you have made your own, I'm interested to see if you actually managed to hear a difference - so please post ABX logs.

 

[BDWoody]

...lower dynamic impedance, the optical stream is cleaner, less polluted, so giving more robust bass, and less undesired treble interference.

Uh huh...

 

[Shoaibexpert]

I have a CCA going into an M500, and haven't had any issues. I hadn't messed with the tone controls before, but after playing with them just now for a few minutes, and other then the obvious frequency changes I didn't notice any obvious distortion or degradation as I moved the sliders around. Was casting from Tidal and Qobuz.

Thanks @BDWoody Your observations kinda match mine...I definitely need it with my HD800S as that's Bass lean. My observation is CCA is cleaner than my Windows PC playing Tidal via USB...maybe I'm mistaken here though.

Was wondering how tone control is implemented on CCA...ideally the bits from say Tidal servers get transferred to the DAC in bit perfect mode via Optical. Introducing tone changes means...either manipulation of the FR is happening inside the phone via Google Home app or inside CCA through a programmable chip which is sitting in the digital signal chain...which I think in EQ enabled would not then be bit perfect. Interesting implementation by Google...