Review and Measurements of New Topping D50s DAC

[b4nt]

So, DPC/ISR and Windows ver/update shall be Ok (attached screen shots above).

Yesterday, I reinstalled the latest ASIO driver. And it worked for several hours, i think (because what I get occasionnaly like superposed is often low level noise).

Now I have the DAC active after power up then some tracks, and currently without any track/app playing. Should be silent. But I again get discrete crackles in my loud speakers... If I were playing some high audio level tracks, I probalbly wouldn't have noticed those ones.

That PC is headless (no mouse, no keyboard, only the DAC and a volume control knob). The DAC is powered using a 5V 3 amp low noise linear supply. One of the nice Chineese USB cables I'm using for the DAC worked fine on another setup (Linux), for several years.

I'm now switching back to MME without the ASIO driver for more than half a day.

 

[b4nt]

Now and without a track playing, I got a one shoot short low level hiss using MME (I shall test that during more than some hours). My speakers are sensitive, if that pops in a track, according to music and audio level, it will be audible.

At this point, I suspect the power supplies (especially that of the PC, can be up to very noisy). I've ordered a USB to Toslink adapter (for galvanic isolation) to check that point.

On another setup, I have an Aune S16, which never supperposed such noises. One reason for which I choosed that model is that it embeds galvanic isolation between the XMOS and the FPGA/DAC chips. I don't think the D50s embeds such a feature, an ADUM or equivalent chip (plus a transformer for coax isolation):

.

 

[Berwhale]

I switched to optical connection between my PC and D50s due to occasional clicks/pops that were audible to me. I was using a cheap ADuM4160 USB isolator to fix a ground loop issue and I wonder if the isolator was somehow responsible for the unwanted sounds.

 

[b4nt]

I switched to optical connection between my PC and D50s due to occasional clicks/pops that were audible to me. I was using a cheap ADuM4160 USB isolator to fix a ground loop issue and I wonder if the isolator was somehow responsible for the unwanted sounds.

The ADUM range for USB connections dongles shall correctly isolate grounds and PSUs (up to 1500V or 2500V spikes). But they aren't adequate, as those components are limited to 12Mbps (may allow max 44.1k/16 bits). Full speed isolators for higher rates and to be fit betwen PC and peripherals cost much more...

The ADUM chip inside the aune S16 is appropriate for higher USB speeds.

Click/pops can be caused by data losses (either by Windows/Linux/OS or due to a bad USB cable). Ground loops should produce constant hum, not occasionnal pops?

Waiting for my Toslink adapter, I quickly modded a USB cable using a handy big inductor. If I'm getting noises due to PC 5V USB power line, they shall so be reduced also. I've just cut the 5V line, inserted the inductor, maybe a 1 to 5mH model, I didn't check:

 

[b4nt]

It sounds now different. I'm again using ASIO, and got a superposed noise. But that was now a surprising loud and long bass event instead of some hiss, cracks or pop

If anyone is trying this:
- split a USB cable, dont cut the data wires
- find a big 1 to 10mH inductor (for example, inside an old PC power supply)
- add two capacitors, from the inductor ends to the ground, shall be safer, I used two 1000uF/10V/105°C

 

[b4nt]

So far, seems to work, with the inductor and the added 1000uF capacitors. I canceled the Toslink adapter order. If this power filter is satisfying over the next days, I'll box it. For the time being, I've taped it, to avoid short circuits.

By the way, I'll keep all the D50s features, including DSD, so on, as it will remain directly connected to the PC. It will be cheaper than a Toslink adapter, and a way cheaper than a high speed USB isolator (200 to 300€).

It is a basic and well known Pi filter, with an inductor on positive 5V rail only (to keep a common and acceptable ground reference between the PC, the DAC, the amplifier). Google will link to more infos.

 

[Gradius]

I have ZERO noise issues here, is totally in inaudible range.

I just use a high quality USB cable, from there I took out the +5V (just isolated the pin) to avoid any power coming from PC.

For power supply I use a MeanWell. Your problem sound more like from USB IC, USB drivers, than other thing.

I'm using 19043.1055 too. Glad the caps might be fixed the issue for you.

Btw, I opened my D50s and cleaned all the soldering flux before using it for real (long term).

 

[b4nt]

That filter on the USB line shall have an effect according to the big bass noise I once heared, with the inductor only. I removed it

Because I had again similar noise using it. Then I switched to BT, with USB disconnected, got some same and similar noise again. Meaning should not be on PC/USB side.

I swapped now also the DAC PSU for a power pack, for less groundings. Not better. Noise is just poping out randomly, sometime, whatever I do.

So now I've to check the DAC/RCA cables/Amplifier side (and maybe have to add a mains filter).

I've received the DAC two months ago. Had no such issue at that period, all was working fine. Looks like I wrongly assumed the cause was Windows, maybe due to recent upgrades, and because there are mixers inside, between apps towards the output.

Since, temperature raised also, summer time.

As a next trial, I'll now change the RCA cables (cheap entry range cables). Whilst touching them at rear of the DAC and accidentally changing their bending, I triggered such similar noises, hiss

Do I have moved or over bend those RCA cables since last month? I've now routed them with less bendings and testing/listening again (since days, I may have no noise for hours, then some pops...).

I found that video on Youtube, about a patch generating noise, and generating more or less noise according to the signals it carries, my RCA cables might now be my issue, according to what I notice whilst touching/bending/slightly over bending them:

After what, I may have to swap and test the amplifier, he is getting hotter than last month, whilst I hadden't such noises.

Btw, I opened my D50s and cleaned all the soldering flux before using it for real (long term).

In house, remaining extra flux shall have no effect before years. It can cause oxydation according to ambiant humidity, but not before a long period.

 

[Gradius]

Just return the thing (RMA) and get a good one on return.

 

[b4nt]

Just return the thing (RMA) and get a good one on return.

What do you suggest me to RMA? I would be happy with the definitive solution

I have now no more pops since last night. I've changed the RCA bendings/routing. I now hope this is the issue... and will be fixed in some hours only, if I get no more pops/hiss.

I'm using the DAC with an amp without preamp. And mostly listening at low levels (currently, my DAC attenuator is at -55dB). Added occasionnal noise isn't noticeable with pop/jazz tracks, much more with vocals tracks only.

Am I at some limits with signal levels and those RCA cables? They would be throw away, I paid approx 10€ for.

 

[b4nt]

Found a vintage 30 years old basic RCA cable in my stock. Using it, I can touch or seriously bend it without generating noise/hiss. Anyone interested? Won't be cheap, still works great and is authentic vintage

Payed 10 for the other, can be bought for 4€ on the Internet. Since I rerouted and unbended it (radius of 5 to 3cm not Ok), I got no more noise. That took some time, where most discussions on the Internet point to packets/buffers drops in PC, settings, PSU noise, groundings.

Still waiting for confirmation, as it was poping very randomly, often spaced in time. And instead of Toslink adapter, I ordered 20dB RCA attenuators, to raise the signals on my RCA cables, for better SNR there.

 

[b4nt]

I have ZERO noise issues here, is totally in inaudible range.y

I just use a high quality USB cable, from there I took out the +5V (just isolated the pin) to avoid any power coming from PC.

I had a lot noise here, random over the days, and now less and less. The latest, I noticed my amplifier had a faulty mains IEC socket: moving the cable was producing noise also. Bad or poor contact inside the 220V socket, that is now swapped out.

I tried to cut the 5V VUSB. But my DAC went down few minutes later, never came up again. I noticed Y cables exist for that purpose, to get USB signals from pc and 5V from a not so noisy PSU. But using such a Y cable seems to violate USB standards (DAC USB port may be powered whilst PC is not, which is bad (because the DAC will try to initiate USB connection as it assumes VUSB is present.... and it will send 5V to the powered down PC, via D+/D- lines)).

I'll keep direct PC connection instead of a Y cable, with a 5V VUSB filter (inductor plus capacitors), and will add a USB EMI filter. Wurth and others seem to have affordable solutions for this, costs some €15 to 20 for a decent USB 2.0 filter. I'll prefer that compared to other but more expensive "magic" dongles, will be less expensive also compared to USB isolators.

Such a dongle will eliminate noise on both 5V and USB D+ D- signals lines. Keywords for Google are: usb+2.0+emi+filter

This shall not affect the audio, only clean up 5V VUSB and the digital signals, what the pc outputs: https://www.element14.com/community...4-the-usb-interface-from-an-emc-point-of-view

 

[b4nt]

Hi, some news,

Testing and checking what I've done at the amplifier side and the analog part, I've finaly found the source of my random weird noises.

4G noises (not the well known 2G bips):

I do not get such high levels of noise in my config. Mine are discrete, their shape or pattern is different, they poped in randomly, spaced by 30 minutes up to 24 hours.

I did a lot of tests over last days and weeks, including with my cell phone. But with my previous RCA cables I used, I did have a different pattern, and much louder noises, not that weirds that popped randomly in.

I finally catched the trigger or source, and the exact same popping/random/discrete noises patterns, with new and different RCA cables. Using my phone top of DAC, and scrolling like in that video, using Twitter. I am very happy so, that will now be manageable

I do not use my phone that much, it is just laying around, more or less close to the DAC when I have the music on. For calls, I mute the music. So I didn't catch the relation. Phone is now thrown away

 

[Mataempat]

So i just got my D50s with A50s and P50. However, I have noticed in device manager that there is a device called d50s DFU which windows can't a driver for. Otherwise the dac works just fine.

Where can i find this DFU driver?

 

[JohnYang1997]

So i just got my D50s with A50s and P50. However, I have noticed in device manager that there is a device called d50s DFU which windows can't a driver for. Otherwise the dac works just fine.

Where can i find this DFU driver?

Just install the official XMOS driver from our website. Make sure to unplug the dac from PC while installing the driver.
https://www.tpdz.net/newsinfo/517089.html

 

[Mataempat]

Superb! Thank you John.

 

[Mataempat]

@JohnYang1997 a quick question out of curiosity and for my own education:
Why is that in Windows, the selectable bit rate and depth only goes up to 32bit 384khz?

 

[JohnYang1997]

@JohnYang1997 a quick question out of curiosity and for my own education:
Why is that in Windows, the selectable bit rate and depth only goes up to 32bit 384khz?
View attachment 140696

This is due to the limitation in the windows audio stack. You can use foobar2000 or other player to play higher sample rate files via ASIO. (although I don't think there's published 768khz music available)

 

[b4nt]

This is due to the limitation in the windows audio stack. You can use foobar2000 or other player to play higher sample rate files via ASIO. (although I don't think there's published 768khz music available)

From what I understod, Windows internals remain at 44.1/16, but he data to the DAC is resampled to the higher rate and bits set there. I left that at 44.1/16 or so (do not care, this is used by web browser, YT, Netflix...).

The way to go beeing Foobar or such, and selecting the ASIO device. So only I see rates changing on DAC display, according to the track rate.

Correct?

 

[JohnYang1997]

From what I understod, Windows internals remain at 44.1/16, but he data to the DAC is resampled to the higher rate and bits set there. I left that at 44.1/16 or so (do not care, this is used by web browser, YT, Netflix...).

The way to go beeing Foobar or such, and selecting the ASIO device. So only I see rates changing on DAC display, according to the track rate.

Correct?

Basically correct.

Windows can output 384khz. You can measure frequency response up to half of the FS. It's just everything gets resampled to the selected format.

Asio bypasses the whole stack directly talking to the driver.