Douk Audio U2 Pro DDC - Poorman DDC for an affordable & clean digital signal

[monsterbill]

Don't forget about aditional $20 HF filtering dongle on a DAC side of the cable.

Hi, I searched the thread for HF filtering dongles, but couldn't find a previous reference. Does anyone have a link to one of these?

 

[sajunky]

Hi, I searched the thread for HF filtering dongles, but couldn't find a previous reference. Does anyone have a link to one of these?

Oh, i.e. one post before yours.

First link ~$20.

 

[Jake2]

Now, the Audio Loop Eliminator/Isolator can be powered by an outside PS- and I do have one. The PW-05 https://www.ebay.com/itm/174916750687 which measures .2uv ripple. Basically no noise.- if they are not lying. The power supply makes a noticable difference in SQ.

But I had an idea. Between the PW-05 power supply and the Audio Loop Eliminator/Isolator I want to place a isolator which costs around $10. https://www.aliexpress.com/item/1005002291935745.html

I realize the isolator is not high speed- but it is only isolating the dc cable between my power supply and dongle- so high speed is not needed as data is not being transfered- but only power. Could this isolator improve the effect of the PS on the dongle- or would it make no difference?

I never thought of using an isolator to isolate noise from a PS- but why not. Funny thing is- I could go furthur and power the isolator https://www.aliexpress.com/item/1005002291935745.html which is isolating the PS from the dongle with another power supply. Don't think I'll go that far.

I do the equivalent of this with the somewhat more expensive Ifi DC iPurifier on the 5v power supply into my Wisdefender isolator. Very effective at elevating - actually pretty much doubling the performance of - an Ifi Power X and a Topping P50 whether feeding this or other devices like my Afterdark Rosanna bridge (though that really deserves a Farad or similar) and a S/pdif IPurifier.

 

[Jake2]

I should clarify I already had a spare DC iPurifier2 (I got a second after being so impressed with the first one) and couple of power supplies after rejigging my system so tried em with the Wisdefender. I imagine there will be a limit to the DC iPurifier2’s ripple smoothing abilities, I expect it’d make less of a difference to an already ultra-low noise/ripple PS.

 

[Mr BubbaHyde]

Glad to hear that! We appreciate the support!

Have you seen our new LAN iPurifier Pro? I have one now and am impressed with its capability!

Yes I know it’s somewhat controversial to some but oh well

Cheers!!

 

[Jake2]

Glad to hear that! We appreciate the support!

Have you seen our new LAN iPurifier Pro? I have one now and am impressed with its capability!

Yes I know it’s somewhat controversial to some but oh well

Cheers!!

I have indeed and it seems a neat unit. I have three of its non-Pro siblings, and a few different grades of FMCs - not controversial at all to me, the sound improvements speak for themselves.

 

[monsterbill]

Glad to hear that! We appreciate the support!

Have you seen our new LAN iPurifier Pro? I have one now and am impressed with its capability!

Yes I know it’s somewhat controversial to some but oh well

Cheers!!

Do you have a picture of the *interior* of the LAN iPurifier Pro that you could share with us?

 

[iFi audio]

Do you have a picture of the *interior* of the LAN iPurifier Pro that you could share with us?

Sure!

I won't muck up this thread, more info here!

https://www.head-fi.org/threads/you...ifier-pro-under-new-silentpower-brand.973159/

Cheers!!

 

[monsterbill]

Recently I bought a bunch of the stuff from Aliexpress (summer sale!) that had been recommended or identified on this thread. Since a lot of the posts seem to be identifying items based on description, but not actually verifying seller or product, I'm happy to post my results if there is an interest.

I'll start with this one: the $20 high-frequency filtering dongle (https://www.aliexpress.us/item/3256...48701802H9ZxLR&gatewayAdapt=glo2usa4itemAdapt)

*Short Answer*
Mostly a bust, but my experience might not be typical (see below). Nerfs the highs and loses space and detail when used in the signal path, but has utility elsewhere.

*Long Answer*

Aliexpress experience:
*Arrived quickly, well packaged and working.
*Shipping price is really high--$11 per dongle and somehow even higher per dongle if you buy several. The vendors on Aliexpress often welcome haggling, and this seller was no exception. I recommend reaching out if you want reasonable shipping pricing.

Experience in my systems:

I tried it in two different setups: (1) computer USB-->USB isolator-->DDC optical output-->Chord Hugo 2; and (2) Raspberry pi-->USB isolator USB output-->Schiit multibit DAC card.

I wasn't able to use the dongle right before the DAC (@sajunky's recommendation) in either setup. Obviously, for the setup #1, I couldn't use it before the DAC since I'm using an optical output. For setup #2, I'm using a Raspberry Pi with Volumio, and inserting the dongle anywhere between the Pi and the DAC prevents Volumio from seeing the DAC correctly and causes a Volumio error.

I tried it in every other place I could in the signal path for Setup #1 (right at the computer USB, before and after the USB isolator, without the isolator, and with both the u2 pro and a different DDC). In each case it sounded pretty bad to me. Sure, there was some noise reduction (blacker blacks), but at the cost of a lot of high frequency information. So, space and higher frequencies were gone. Snare drums sounded scratchy. No stage. No bueno.

I also tried it outside of the signal path, on adjacent USB ports. There may have been an improvement, but honestly so subtle that I wouldn't be able to pick out it out a blind A-B I'm sure.

Lastly, I also tried it on the power input for the raspberry pi and a few other places. Finally, a victory. It did remove some noise when used in this manner without any audible downsides.

I tried a couple DDCs and USB isolators discussed on the thread and happy to share experiences if there's an interest. My setup (in particular using optical) is weird and probably leads to different results, but let me know.

--MB

 

[monsterbill]

DXIO PRO3Zi
Next up is my first attempt at upgrading my U2 Pro. The DXIO Pro3zi was compared favorably against the U2 Pro on another forum by a trusted poster. It's also the one off-the-shelf DDC I could find that has the NDK oscillators discussed in this thread.

Can be bought here for ~$240:
https://www.diyinhk.com/shop/audio-...spdif-with-ultralow-noise-08uv-regulator.html

*Short Answer*
Unit failed in less than a day, but sounded pretty good until that point.

*Long Answer*
Purchasing experience:
Seller ships direct from Hong Kong. There were two shipping options, free freight shipping and $30 FedEx. I opted for FedEx based on bad experiences getting freight from China. Still took a few weeks. Arrived safe and well packaged. Seller refunded after unit failed.

Experience in my system:
My setup was Computer USB-->DXIO Pro3zi (optical output)-->Chord Hugo 2. At the time I didn't have a USB isolator.

Compared to U2 Pro (without a USB isolator) it was a marked improvement. Much lower noise floor. It struck me as a similar upgrade as going from using my crappy optical output on my ancient IMac to using the U2 Pro.

But...the optical output on the DXIO failed within a day. The seller refunded after some back-and-forth, which ended with him asking me to take pictures of myself smashing the DXIO with hammer. (Trying not to kink-shame, but it felt kinda dirty.)

Epilogue:
Now that I've tried the U2 Pro (basic version, basic clock) *with* a USB isolator, it sounds great. On memory, the U2 Pro + isolator sounds about the same as I remember the DXIO (with no isolator), but it's been a while. (If I'm to believe the hype, this could partly be due to jitter-resistance in my DAC, making the improved clock on the DXIO less beneficial.)
--MB

 

[sajunky]

Epilogue:
Now that I've tried the U2 Pro (basic version, basic clock) *with* a USB isolator, it sounds great. On memory, the U2 Pro + isolator sounds about the same as I remember the DXIO (with no isolator), but it's been a while. (If I'm to believe the hype, this could partly be due to jitter-resistance in my DAC, making the improved clock on the DXIO less beneficial.)
--MB

Thanks for sharing all. Which USB isolator did you chose?

U2Pro main weakness is lack of isolation. A pair of the USB isolator with U2Pro is a seamless solution. It is why we talk about isolators in this thread.

I managed to get good results before inexpensive USB isolator devices appeared on the market, but my experience only confirms that isolator is needed, in most cases neccessary.

You are right saying that on the optical connection having ultra-low jitter oscilators is little bit wasted feature. I agree. Before upgrading oscilators on my U2Pro it was not a big difference between optical and coax, but now it is. Coax output sounds much better. And a Pulse transformer on U2Pro does a job at 192kHz despite a claim it is inappropriate. But I am thinking that upgrading oscilators would be still beneficial. It is worth upgrade if made inexpensive (DIY). Do you use external PSU for the USB isolator and/or U2Pro?

 

[monsterbill]

Thanks for sharing all. Which USB isolator did you chose?

I tried two with the U2 Pro:
*this Adum3166 https://www.aliexpress.us/item/3256806826164578.html
*and this Adum4166
https://www.aliexpress.us/item/3256806536179857.html

While they both worked and sounded good with the U2 Pro, I can't really recommend either for AliExpress reasons. The Adum4166 failed after a day, and started emitting a screeching sound from its chassis. The Adum3166 came in a beat up soft envelope (no box or padding) with a gaping hole, was branded differently, and put together partly with glue repairs.

I'm returning the Adum4166. The Adum3166 is now working happily in between a raspberry pi and schiit multibit card. If you all are buying the Adum3166, I'd recommend buying from a different seller.

 

[monsterbill]

@sajunky, could you please recommend a usb isolator to work with this Ustars U19 ddc: https://www.aliexpress.us/item/3256805599322441.html I'm having trouble finding one that works properly with the U19.

The U19 sounds better straight from the computer USB than with the Adum4166, which sounded very harsh. The U19+Adum3166 sounded great--for about half a song--and then started playing SUPER LOUD white noise. (Kinda like when there is a bitrate problem.)

The U19 shares some DNA with Amanero products, and I hear that Amanero DACs are hard to match with USB isolators. Unfortunately, the U19 does need some added isolation in my set up. I'm currently connecting the U19 to a self-powered Anker hub with 2.0 cables, but it's not ideal and a little grungy.

For comparison, the $220 U19 (with no isolator) sounds more harsh than the U2 Pro + USB isolator, but the U19 has a beguiling character with vocals. Hard for me to put into words, but there is more of a sense of space and differences in mic placements and maybe more body with the U19. I think the U19+the right usb isolator is what I'm looking for. (Caveat--I'm wary this pursuit is my wallet talking. The U2 Pro+usb isolator is very good, and I'd probably just switch back to that if I can't figure out an isolator for the U19.)

 

[sajunky]

I tried two with the U2 Pro:
*this Adum3166 https://www.aliexpress.us/item/3256806826164578.html
*and this Adum4166
https://www.aliexpress.us/item/3256806536179857.html

While they both worked and sounded good with the U2 Pro, I can't really recommend either for AliExpress reasons. The Adum4166 failed after a day, and started emitting a screeching sound from its chassis. The Adum3166 came in a beat up soft envelope (no box or padding) with a gaping hole, was branded differently, and put together partly with glue repairs.

I'm returning the Adum4166. The Adum3166 is now working happily in between a raspberry pi and schiit multibit card. If you all are buying the Adum3166, I'd recommend buying from a different seller.

Be careful what power supply you connect to these devices. Low noise LDO regulators do not have sufficient non-destructive voltage margin or will fail from overheating. But a screeching sound could only come from the internal DC/DC converter, it indicate failing from overvoltage.

Also be careful what you are ordering. The 3166 model on this link is selling with two options:
$32.02 - Color: NO Shell, (default)
$35.99 - Color: with Shell

It seems you have received what you paid for.
And a glue "repairs" are frequently mistaken with factory silicone padding reducing microphonic effect. This seller specialise in HF components, they know their job. I think they don't deserve bad publicity.

 

[sajunky]

@sajunky, could you please recommend a usb isolator to work with this Ustars U19 ddc: https://www.aliexpress.us/item/3256805599322441.html I'm having trouble finding one that works properly with the U19.

The U19 sounds better straight from the computer USB than with the Adum4166, which sounded very harsh. The U19+Adum3166 sounded great--for about half a song--and then started playing SUPER LOUD white noise. (Kinda like when there is a bitrate problem.)

The U19 shares some DNA with Amanero products, and I hear that Amanero DACs are hard to match with USB isolators. Unfortunately, the U19 does need some added isolation in my set up. I'm currently connecting the U19 to a self-powered Anker hub with 2.0 cables, but it's not ideal and a little grungy.

For comparison, the $220 U19 (with no isolator) sounds more harsh than the U2 Pro + USB isolator, but the U19 has a beguiling character with vocals. Hard for me to put into words, but there is more of a sense of space and differences in mic placements and maybe more body with the U19. I think the U19+the right usb isolator is what I'm looking for. (Caveat--I'm wary this pursuit is my wallet talking. The U2 Pro+usb isolator is very good, and I'd probably just switch back to that if I can't figure out an isolator for the U19.)

A nice mini-DDC. Amanero has two modes of operation. UAC 2.0 and bulk mode. Without Amanero drivers Win10 and above works in UAC 2.0 mode. With drivers installed it is identified as a "Digital Interface", works with WASAPI in bulk mode, like a hard drive. Which mode do you use? Try another one.

I don't expect compatibility problems with a licenced Amanero product. Not sure this one is licenced though. When you hear opinion of compatibility problems, verify it is about new generation of isolator or some old, based on a discontinued Silanna chip. I am interested to hear too, using Amanero receiver, please let us know.

In this case insufficient USB Bus power is probably an issue. It is why I asked a question:

Do you use external PSU for the USB isolator and/or U2Pro?