What brand & model?
Holo Audio Red https://www.kitsunehifi.com/product/holoaudio-red-ddc-network-streamer/
What brand & model?
When inserted into the signal path, the Holo Red functions either as streamer or DDC. If one is streaming from a laptop and has a μDDC, the Red is superfluous. There is no reason to insert it into the signal chain.
If one is using the Red as a streamer, the only real reason to consider a μDDC is if one feels there is an audible advantage to the latter's clocks.
Agreed from noise point of view. However adding extra USB isolator before uDDC is more logical an economic.Daisy chaining Red to uDDC would yield to even more transparent sound since you're also further isolating the signal from the noise generated by Red. However, you must use the USB out of Red
It would be very good connection if DDC had external clock output. By example DI-25 has 10MHz output. DAC will be synchronised to a DDC internal clock.and not SPDIF to hear the benefits since IME, daisy chaining SPDIF interfaces yields to more jitter (and requires an external word clock to keep the devices in sync)
I have it and it's indeed excellent using the usb out. You need a good 6v psu (it comes with a walwart).Apologies folks if a bit OT but FYI @venomas200 here’s my budget DIY alternative to the Red in streamer mode with USB audio out. An AliX Ustars C19 streamer > Altor USB regen. The Ustars has a looong French hifi forum thread praising its performance vs more expensive streamers especially when fed really clean power say with in-line super-capacitor filtration. The Ustars uses the barebones RPI CM4 board as does the Red, omitting electrically noisy unneeded functions like wifi and Bluetooth transmitters. It supports a similar range of streaming apps as the Red, though I intend to flash it with the HQP NAA OS.
I bet the uDDC would sing being fed USB by this combo.
Good thing about both the Altor and C19 is you can spend as much or as little as you want on the 5V power supply for each (the C19 states 6v but you can use 5v, for my version at least). Or spend nothing on the PS in the case of the Altor that sounds very good just running off USB bus power. But once you hear the benefits of an even cleaner, lower noise PS it’s hard to stop there…
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Sorry, you did say you already had a Red on the Harmony DAC thread, my bad. Only way to find out fer sure what’s better to your ears in your system is buy a uDDC and compare, judge for yourself. Good luck with that decision. In the meantime I’ll be interested to hear how you get on with the Altor, the Red and the Harmony DAC.II have a Red , and I have RPI5 8 gb version in my home. I'm waiting for Altro USB. So I consider remove out red from my chain and put uDDC . And what's is better for my Harmony dac
I haven't tested with 5v. It could be possible to use 5v with the version with ext clock input but perhaps not with the version with built-in ocxo.Apologies folks if a bit OT but FYI @venomas200 here’s my budget DIY alternative to the Red in streamer mode with USB audio out. An AliX Ustars C19 streamer > Altor USB regen. The Ustars has a looong French hifi forum thread praising its performance vs more expensive streamers especially when fed really clean power say with in-line super-capacitor filtration. The Ustars uses the barebones RPI CM4 board as does the Red, omitting electrically noisy unneeded functions like wifi and Bluetooth transmitters. It supports a similar range of streaming apps as the Red, though I intend to flash it with the HQP NAA OS.
I bet the uDDC would sing being fed USB by this combo.
Good thing about both the Altor and C19 is you can spend as much or as little as you want on the 5V power supply for each (the C19 states 6v but you can use 5v, for my version at least - Correction - I’d read it worked with 5v on the French forum, but it was flaky just now testing that, so as Fred says, needs 6V). Or spend nothing on the PS in the case of the Altor that sounds very good just running off USB bus power. But once you hear the benefits of an even cleaner, lower noise PS it’s hard to stop there…
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I'm waiting for delivery AltroSorry, you did say you already had a Red on the Harmony DAC thread, my bad. Only way to find out fer sure what’s better to your ears in your system is buy a uDDC and compare, judge for yourself. Good luck with that decision. In the meantime I’ll be interested to hear how you get on with the Altor, the Red and the Harmony DAC.
The YouTube Old Guy Hifi channel has a review of the Laiv uDDC just posted. He really thinks it improves any DAC it is connected to, including the Laiv Harmony DAC. I got the uDDC last week and it certainly improves my Holo Audio Cyan2, this is also compared to another DDC I have, the Denafrips Hermes model. The soundstage improves a lot in clarity and extent while retaining the mass of sound, I felt the Hermes in contrast gave a thinned out feeling as the soundstage increased, a bit artificial. So to my ears the Laiv uDDC is an excellent device, only feature it lacks is not having more than one digital output, two simultaneous I2S outputs would be excellent.
Source is an Eversolo DMP-A6 streamer with an upgraded LPS feeding over USB into an LHY Audio UIP, output into miniDSP SHD Studio, I use this for Dirac Live and miscellaneous PEQ. Come out via AES into Laiv uDDC (or Denafrips Hermes), then I2S into Holo Audio Cyan2 DAC. I use an iFi iPower2 on the uDDC by the way. This DAC is NOS only, and the SHD Studio resamples everything to 96 kHz so this is the sample rate the Cyan2 finally sees. I don't have any external 10 Mhz clocks currently to try on the UIP and the uDDC.In the video, he also echoes the performance benefit of the SMSL PO100 Pro, which has been noted by Randy (Cheap Audio Man) as delivering an improvement for Geshelli DACs, which do not have galvanically isolated USB (the LAIV Harmony and all Holo Audio DACs do). With the PO100 Pro, I've not been able to pass PCM >192kHz (via HQ Player) to a Geshelli J2S despite its claimed 768 kHz USB rating, so that remains a puzzle here and gives me cause for concern about DDCs in general.
On a different note, I was in a conversation with a Holo May user who just put his Denafrips Hermes up for sale, finding it provided no audible benefit vs. a direct USB connection to his Lumin streamer, so there's that, but it does raise questions...
Two relevant questions are: (1) What is your source? (2) Are you using your Cyan 2 in NOS mode or ...? I ask because (1) it seems that certain source devices seem to accrue consistent complaints about poor USB performance, which would have to be terrible to affect the outcome at the destination (which holds the master clock). (2) HQ Player brings benefits similar to what youd described (extended resolution and soundstage), although the μDDC is limited to an input of 768 kHz PCM, which is half the Cyan 2's rated PCM input and HQ Player's max PCM upsampling rate. That shouldn't present an issue for anyone converting to DSD with ample CPU power, but worth noting nonetheless. One benefit the μDDC brings to the Cyan 2 regardless however, is input switching. The μDDC makes for a rather expensive switch, but it's an added value if the μDDC delivers a reliable, repeatable performance benefit.
Source is an Eversolo DMP-A6 streamer with an upgraded LPS feeding over USB into an LHY Audio UIP, output into miniDSP SHD Studio, I use this for Dirac Live and miscellaneous PEQ. Come out via AES into Laiv uDDC (or Denafrips Hermes), then I2S into Holo Audio Cyan2 DAC. I use an iFi iPower2 on the uDDC by the way. This DAC is NOS only, and the SHD Studio resamples everything to 96 kHz so this is the sample rate the Cyan2 finally sees. I don't have any external 10 Mhz clocks currently to try on the UIP and the uDDC.
So I have been listening to the two cases you wanted me to evaluate. So first case is straight from DMP-A6 streamer over USB into Holo Audio Cyan2 DAC. Second case is streamer over USB into Laiv uDDC then I2S into same DAC. First impressions are that they are quite similar, but as I listened further and switched back and forth, I definately preferred the second case with the uDDC in the path. Just a bit better soundstage clarity and contrast, a bit more depth maybe. But not an overwhelming or large difference, subtle enough really. Perhaps one thing to note is that the hdmi cable used for the I2S case is not present in the first case, this cable is an AudioQuest Cinnamon 48G, maybe it is having an effect on matters. A different hdmi cable is arriving today and I will listen some more.Ah, ok. I would really be interested to see an evaluation using a straight USB connection between the A6 and DAC with and without the μDDC via I2S. This is the way to evaluate the μDDC against the Cyan 2's internal clocks, as with asynchronous USB, the destination holds the master clocks. The other inputs use the source device clocks, so in this chain presently, it is the SHD Studio that is being evaluated against the μDDC.