Steve Woodhouse
Major Contributor
- Joined
- Aug 11, 2023
- Messages
- 1,274
What do you mean by that?
Digital in via coax, measured output from RCAs.
What do you mean by that?
Coaxial input in the Ultra?
Sometimes it's via toslink input, sometimes a network streaming is used. In the last example toslink wasn't used.
Measured signal level vs frequency, as usually for FFT graphs.
dBFS or dBr, usually, but Volts sometimes as well.
Its all in the thread .What about the power supply in the Ultra, is it good? Whouldn’t it be better with the possibility to choose which power supply to use With Ultra?
Given you can't with the Ultra, that's rather moot, plus discussions about the use and impact of power supplies, particularly where the digital (particularly optical) output is being used are always contentious.What about the power supply in the Ultra, is it good? Whouldn’t it be better with the possibility to choose which power supply to use With Ultra?
To be fair , regarding thd , this is what Onlyoneme measured in the first page .2021..same chip , single too etc![]()
Topping DX3 Pro+ Review (DAC & Headphone Amp)
This is a review and detailed measurements of the Topping DX3 Pro+ DAC and headphone amplifier. It is a replacement for one of my most favorite combo products, the DX3 Pro. It was sent to me by the company and costs US $199. The DX3 Pro+ maintains the gorgeous and high contrast orange LEDs...audiosciencereview.com
wiin announces either -115 or -116 for the ultra...according to the sources (unwieght too) consistent....
To be fair , regarding thd , this is what Onlyoneme measured in the first page .
As one can see, the THD is lower on the ultra within 20-20000 Hz than with the PRO+.
Its -123,6 dB !
View attachment 9550
Onlyoneme :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
For all the following tests I will use the LPF, except stated otherwise.
The Dynamic Range, 120.1 dB.
View attachment 9361
THD vs level, for 1 kHz test tone:
View attachment 9375
IMD vs level, for SMPTE test tone:
View attachment 9376
A small sign of ESS hump is visible. I said in the comments, based on quick tests, that it wasn't visible with the LPF, but I was wrong.
J-test for the analog output. I've no idea why some people take such results as jitter measurements of the digital outputs...
View attachment 9377
NID multitone:
View attachment 9378
Time for something I would call a noise profile, over the coaxial output. I use both ADC Cosmos and the Scaler plus the LPF, with a termination at 75 ohm just before the LPF. Due to the LPF characteristics I limit the recording sample rate to 96 kHz. As a test signal I use dithered "silence" file.
First result comes from SMSL PO100 Pro, powered by the USB hub:
View attachment 9443
Next one is the WiiM Pro, powered by Sbooster LPS:
View attachment 9444
And the last one is the Ultra, powered by its internal SMPS:
View attachment 9445
we are in thd and deliberately not thd/n....To be fair , regarding thd , this is what Onlyoneme measured in the first page .
THD vs frequency, 192 kHz sample rate.
Analog outputs.
As one can see, the THD is lower on the ultra within 20-20000 Hz than with the PRO+.
Its -123,6 dB . This is sota performance.
View attachment 9550