My Ultra tests

[onlyoneme]

I’m sure I will get hammered on this especially Steve Woodhouse who like busting chops to other users. I have 7 dacs and all modern devices. 3 uses Ess chip different model and using same opa1612. 3 also uses akm different model and using opa1612. Both chipsets measure extremely good. Now, I could not hear the difference version of ess or akm but I could easily hear if it’s akm or ess chipset. How did I do this? I had one guy cover my eyes and sent me to other room while switching dacs through a switch then guide me to the chair blindfolded and ask me which chipset while playing music. We did this 50 times and I got zero error. I am able to pinpoint which chipset being played between ess and akm. Now, if measure identical should sound same so how did I able to tell the difference? Golden ear!

There is no such thing as two devices which measure the same in general, and proven "transparent devices" do not exist either. I can bet that you will not hear differences in the controlled conditions using the same test signal as the one used for measurements, if results give a strong evidence of being below the audibility level. And this is all.

 

[Steve Woodhouse]

I’m sure I will get hammered on this especially Steve Woodhouse who like busting chops to other users. I have 7 dacs and all modern devices. 3 uses Ess chip different model and using same opa1612. 3 also uses akm different model and using opa1612. Both chipsets measure extremely good. Now, I could not hear the difference version of ess or akm but I could easily hear if it’s akm or ess chipset. How did I do this? I had one guy cover my eyes and sent me to other room while switching dacs through a switch then guide me to the chair blindfolded and ask me which chipset while playing music. We did this 50 times and I got zero error. I am able to pinpoint which chipset being played between ess and akm. Now, if measure identical should sound same so how did I able to tell the difference? Golden ear!

I won’t bust your chops, and no offence to you whatsoever.

But I’m not going to believe any individual posting something unverified (and to be clear, I wouldn’t expect anyone else to do so, including anything I posted).

Just in general, I’d count any 100% result from 50 as looking a tad suspicious.

Again, and for clarity, this is no offence to you. I’d apply the same to anyone, and expect anyone else to apply it to me.

What are the DACs?

 

[canard]

There is no such thing as two devices which measure the same in general, and proven "transparent devices" do not exist either. I can bet that you will not hear differences in the controlled conditions using the same test signal as the one used for measurements, if results give a strong evidence of being below the audibility level. And this is all.

akm claims an assumed "velvet" signature... .. would be interesting to ask them, while these machines will meet the criteria asr "transparent" modes...what are they "playing on" for this ;-)



It’s a shame that you didn’t continue to enrich your feedback on the ultra..,-)

 

[steadyshot]

Good question.

Starting at the lower end ,Topping D10 balanced, THD+N 118.5dB (extremely close) SNR 121.5dB (pass), jitter 139dB (pass).

The DX7Pro Plus clears everything. By the way, in relation to onlyoneme’s comments on the WiiM Amp (above), the SNR is 130dB on the balanced out, but only 93dB on the headphone out.

That’s why it’s simply not possible to measure the DAC alone on that model.

Dx7 pro plus does not clear imd target of -120db. Scroll down the asr review and you will see .

Topping DX7 Pro+ Review (DAC & HP Amp)

This is a review, detailed measurements and listening tests of Topping DX7 Pro+. It was sent to me by the company and costs US $699. As you see, the DX7 Pro+ sports the newer look of some Topping products. I did not care for it much before but it is growing on me. :) Three different headphone...

www.audiosciencereview.com

 

[Steve Woodhouse]

Dx7 pro plus does not clear imd target of -120db. Scroll down the asr review and you will see .

Topping DX7 Pro+ Review (DAC & HP Amp)

This is a review, detailed measurements and listening tests of Topping DX7 Pro+. It was sent to me by the company and costs US $699. As you see, the DX7 Pro+ sports the newer look of some Topping products. I did not care for it much before but it is growing on me. :) Three different headphone...

www.audiosciencereview.com

Mr.Plug, I’m going to row back ever so slightly on my earlier post. It requires a little detail, more later.

 

[Musician]

It's going to be a long time process, but I will try to add a new content periodically. Everything based on the pre prod device which is PCB ver 2 unit.

Just one thing at the beginning, a comparison of the waveforms over the digital coax output, tested with the oscilloscope and 192 kHz sample rate test signal, and terminated at 75 ohms.

This is for the Ultra:

View attachment 8954

And this is for the Pro/Plus:

View attachment 8955

Ideal and perfect waveforms would show rectangles. In the real world it should be as close as possible to the ideal one.




A rough comparison of the Pro Plus with the Ultra, THD vs frequency, 192 kHz sample rate. It's not a THD+N, so it's not a sinad. And this is over the analog output using full scale sine signals.

View attachment 8971

The "hills" here would require some explanation, but I'll spend some time on that a little later with my personal perspective on other measurements results which I've faced.




Few words on the noise on the analog output. I use 192 kHz sample rate and a dithered silence file to keep the output active.

First result is taken when the Ultra is connected directly to my ADC, screen is off:

View attachment 9045

and with the screen on:

View attachment 9046

10 kHz component (and harmonics) appear.

Now the same test but also with the scaler, so that's the setup I use most of the time, screen off:

View attachment 9047

and the screen on:

View attachment 9048

One of the differences between above setups is the input impedance, 1.2 kOhm vs 100 kOhm. I've made some additional tests with RME UCX II and 5 kOhm and 9 kOhm impedances, and observed results lied between these above, being closer to the ADC alone with its low input impedance. I guess that the noise pollution from the PSU is strong enough to reveal itself when high impedance input is used. And it can affect measurement results.
Personally I prefer to see something as below, the Pro Plus powered by an LPS and with the scaler, so high impedance input is used:

View attachment 9051


As I am still suspicious, I made another test with the LPF (which I use for class D amps measurements) attached. The scaler is used again:

View attachment 9052

Noise pollution is highly attenuated, so maybe it comes from the high frequency noise made by the PSU. I looked at the spectrum of white noise to verify how the DAC filter (there are 7 of them BTW) handles is. Below a comparison with the Pro Plus:

View attachment 9053

It doesn't look good to me.




And something for those sinad addicted, with an LPF:

View attachment 9065

and without it:

View attachment 9066

Onlyoneme, I hope you dont loose the energy to make measurement because of those fundamentalists from ASR polluting this thread.

I would like to see comparisons with Pro+ ( with stock power supply ) and the Ultra ( without LPF ) using the digital volume control at - 20 dB , both from spdif electrical out ( to see the resolution when used as digital preamps ) and from the analog output after the internal dacs.

 

[canard]

Onlyoneme, I hope you dont loose the energy to make measurement because of those fundamentalists from ASR polluting this thread.

I would like to see comparisons with Pro+ ( with stock power supply ) and the Ultra ( without LPF ) using the digital volume control at - 20 dB , both from spdif electrical out ( to see the resolution when used as digital preamps ) and from the analog output after the internal dacs.

in fact, a good number of measurements will have to be studied at like -20-30db..
I would even be tempted to say that for people listening to demanding acoustic music with significant dynamic differences, the essential musical content can be at low levels... could be those highlighted in the first place...
(besides the famous ess hump easily observable on modest two-tone imds was definitely annoying)

 

[Brantome]

Onlyoneme, I hope you dont loose the energy to make measurement because of those fundamentalists from ASR polluting this thread.

Let’s not descend to the level of name calling that others do - objectivists v subjectivists is probably as strong as we should get. Thanks

 

[steadyshot]

Let’s not descend to the level of name calling that others do - objectivists v subjectivists is probably as strong as we should get. Thanks

Objectivist is not accurate characterization for some people here . Objectivist is one that can draw conclusions within the reach of the available data and remains agnostic about what cannot be extrapolated from the data with high degree of certainty . Manipulating the data does not make you objectivist

 

[Brantome]

Objectivist is not accurate characterization for some people here . Objectivist is one that can draw conclusions within the reach of the available data and remains agnostic about what cannot be extrapolated from the data with high degree of certainty . Manipulating the data does not make you objectivist

Maybe we shouldn’t have any labels then?

 

[Steve Woodhouse]

Onlyoneme, I hope you dont loose the energy to make measurement because of those fundamentalists from ASR polluting this thread.

Unfortunately, comments like this only provide heat, and no light.

 

[Brantome]

Unfortunately, comments like this only provide heat, and no light.

I’ve already asked that we don’t use comments like that, no need to rake over the coals. Thanks

 

[Steve Woodhouse]

Objectivist is not accurate characterization for some people here . Objectivist is one that can draw conclusions within the reach of the available data and remains agnostic about what cannot be extrapolated from the data with high degree of certainty . Manipulating the data does not make you objectivist

I have no disagreement with that.

On a personal level, I appreciate subjectivists more when they accept that, whilst ‘measurements aren’t everything’, they are an awful lot, and always get us most of the way there, if not all the way.

I’d have more sympathy with that than those who appear to ignore measurements, largely or completely.

I suspect many of us are a lot closer than it might first appear.

 

[slartibartfast]

I have no disagreement with that.

On a personal level, I appreciate subjectivists more when they accept that, whilst ‘measurements aren’t everything’, they are an awful lot, and always get us most of the way there, if not all the way.

I’d have more sympathy with that than those who appear to ignore measurements, largely or completely.

I suspect many of us are a lot closer than it might first appear.

Pretty sure my system sounds a bit different every day depending on my mood etc

 

[Brantome]

Pretty sure my system sounds a bit different every day depending on my mood etc

Yeah, and room temperature, humidity etc I suspect too.

 

[slartibartfast]

Yeah, and room temperature, humidity etc I suspect too.

Not forgetting how much alcohol has been consumed

 

[onlyoneme]

I would like to see comparisons with Pro+ ( with stock power supply ) and the Ultra ( without LPF ) using the digital volume control at - 20 dB , both from spdif electrical out ( to see the resolution when used as digital preamps ) and from the analog output after the internal dacs.

I haven't found any differences in my tests in the digital domain for volume processing at -24 dB.

 

[canard]

I haven't found any differences in my tests in the digital domain for volume processing at -24 dB.

it's a lot at the dac level that's interesting...at the digital level past the threshold of 24bit processing (see 32-64 which will be really useful in pro) we can imagine it seems to me a margin is rather sufficient ... ;-)

 

[Steve Woodhouse]

Not forgetting how much alcohol has been consumed

WORD!

 

[Jls]

Regarding the DAC differences: did the identical test results include controlling the volume and making sure the volume was identical? Was this carefully measured and controlled?