Is it correct that this device blocks noise and does not regenerate signal or remove jitter?
Please correct me if I need to be corrected.
Please correct me if I need to be corrected.
LHY UIP USB audio isolator
The LHY UIP galvanically isolates and reclocks the input USB signal signal to deliver a clean output signal - a nice neat “eye pattern” (meaning low jitter), free of upstream electrical noise. The high level of galvanic isolation of the ADuM chip used effectively blocks electrical noise carried on the upstream USB cable’s ground and signal conductors. A reference oscillator is integral to the design of the particular latest generation ADuM USB isolator chips (as used in the LHY and certain other USB isolators) to reclock the output USB signal, to reduce the output USB SIGNAL JITTER*/ timing variation from one square wave wave crest / trough to the next.
So it stands to reason the precision of the reclocking and the cleanness of the output square wave signal (the eye pattern) will vary with the quality of the clock used. This is indeed exactly what I found switching between internal OCXO and a better external clock - very audible, meaning it seems, a cleaner, lower jitter USB signal makes the life of the recipient DDC or DAC easier, resulting in less jitter in the synchronous data stream as used at point of conversion by the DAC to analogue*.
See below video for an overview of how the ADuM chip at the heart of the UIP works,
*NOTE re USB signal jitter vs I2S output jitter
USB signal jitter is not to be confused with jitter in the generation of a synchronous digital audio stream by a DAC or DDC. A DAC or DDC receives an asynchronous digital audio stream of data (eg USB or ethernet) and outputs synchronous via i2S, in the DAC’s case an internal i2S circuit connection, in the DDC’s case via HDMI I2S output. Same general logic holds true for DDCs that output synchronous audio via S/PDIF or AES/EBU. Jitter on the generation of a synchronous digital audio data stream is ultimately all that matters for audio quality, if jitter on USB (or Ethernet for that matter) didn’t impact this at all then we wouldn’t care at all about that. However it seems clear from my experimentation I describe in this thread (and that of AustinPop in his linked review of the Phoenix upthread, and the experience of other folk with the UIP) that the clock used for USB regeneration ( = the level of jitter on a USB signal) impacts this to a surprising degree. This is of course in addition to the usual suspects with DACs & DDCs re jitter - the quality of the internal or external reference clock used by the DDC or DAC to do the conversion to I2S and how low noise their power supply is.
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sajunky
Headphoneus Supremus
It blocks noise on the isolator and regenerate signal.
Audio jitter or USB timing jitter? If the later, yes. Isolator chip recreate timing and it seems there is also on-board USB 2.0 hub chip that fully regenerate complete USB frames.
We can talk about audio jitter once synchronous datastream is created. It happens in the USB receiver in a DAC/DDC, not there.
So- would placing one of those Ali Express or ifi usb dongle jitter minimizers on the output of the LHY help- or would it be just what the LHY is already doing better?
Remarkably it does help, as I said on the Audio-Gd thread. Even helps in front of the far more expensive Innuous Phoenix, though it seems certain combos are not necessarily better.. eg putting the LHY before the Phoenix or the Holo Titanis before the LHY. Not super intuitive. Assume an even higher quality USB source like a high quality streamer would sound better still, it seems everything matters, incl all the Ethernet isolation far upstream (I tested this, still very audible).
If I use the LHY with the DI-24, would I place the jitter dongle on the output of the PC or the output of the LHY or both?
They only cost around $20. I can get two...
Perhaps if you could link to the particular USB dongle you are referring to as not to confuse other readers of this thread who may be unsure what you are referring,
If it’s the same as my AliX one, it’s a basic but good quality galvanic isolator with option for an external power supply.
I use it before the LHY, haven’t tried it after as assumed LHY output would be far superior. LHY certainly is head to head, no contest, not in the same ballpark.
If it’s the same as my AliX one, it’s a basic but good quality galvanic isolator with option for an external power supply.
I use it before the LHY, haven’t tried it after as assumed LHY output would be far superior. LHY certainly is head to head, no contest, not in the same ballpark.
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I think there are basically two types of these dongles. The isolator ones and the jitter reducer ones. This one is a Jitter reducer.- I think.
My hunch is it should go after the LHY..., before the DI-24.
My hunch is it should go after the LHY..., before the DI-24.
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This one would go before the LHY on ther PC output. (isolater type dongle) (I think)
https://www.aliexpress.com/item/100....order_list.order_list_main.27.7f0b1802D9Rj4f
https://www.aliexpress.com/item/100....order_list.order_list_main.27.7f0b1802D9Rj4f
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This is crazy. If the DI-24 and LHY UIP both isolate so well, how can a additional isolating dongle do more?
In my experience- when over purifying, sometimes things get sterile and to thin... I guess it is system dependant.
What I like about what I'm reading about the LHY UIP is it presents a denser, rounder, thicker sound. This is the direction I want to go in.
In my experience- when over purifying, sometimes things get sterile and to thin... I guess it is system dependant.
What I like about what I'm reading about the LHY UIP is it presents a denser, rounder, thicker sound. This is the direction I want to go in.
This is the one I have in front of the LHY - used with Ifi Power X + DC iPurifier2 - effect of both very audible.
It is crazy. Very hard to predict what will sound better as a combination using theory (apart from selecting individual items using principles of like power quality, isolation quality, and also oscillator precision where applicable). Until I tried this I'd have been very sceptical about the quality of oscillators in USB regenerators having any effect on audio quality. I am sceptical no longer.
Incidentally as I posted on the PhoenixUSB thread the sound quality of even that USD4k USB regenerator can be improved by adding a couple of MuMetal sheets on top. Ditto re the LHY UIP. And ditto re the DI-20HE - even with its fancy regenerated power supplies - as @Mr Brett can attest from a joint listening session on the weekend.
https://www.head-fi.org/threads/innuos-phoenix-usb-reclocker.942986/post-18122050
sajunky
Headphoneus Supremus
This is common mode filter. The best use is at the receiving side.
This is equivalent of Ifi Defender. The best use as per Ifi instruction. None of them are isolators. For the latest high-speed isolators look at Douk Audio U2Pro poorman DDC thread.
Gieseler Audio USB Reingen
Incidentally for folk in the market for a USB regenerator/reclocker, here's another option I only became aware of recently - the Reingen by Australia-based Gieseler Audio. It also uses the ADuM 4165/66 chip which is apparently also used by Antipodes Audio. The existing 'Streamline' model has received a lot of positive feedback on Stereonet.
https://www.gieseler.com.au/product-page/usb-reinigen
https://www.stereonet.com/forums/topic/573769-gieseler-audio-usb-reinigen-owners-thread/#comments
They've actually just released a newly Enhanced version. Price wise this (and the base Streamline model) sit a little above the LHY, but much nearer the LHY than the Phoenix, whilst having the Phoenix in their sights performance wise. Pricing in AUD. It'd be fascinating to compare the two, or three, which I may well end up doing if funds and my friendly local Phoenix owner (to whom I've now returned it) permit...
https://www.stereonet.com/forums/topic/615006-new-enhanced-usb-reingen/
Incidentally for folk in the market for a USB regenerator/reclocker, here's another option I only became aware of recently - the Reingen by Australia-based Gieseler Audio. It also uses the ADuM 4165/66 chip which is apparently also used by Antipodes Audio. The existing 'Streamline' model has received a lot of positive feedback on Stereonet.
https://www.gieseler.com.au/product-page/usb-reinigen
https://www.stereonet.com/forums/topic/573769-gieseler-audio-usb-reinigen-owners-thread/#comments
They've actually just released a newly Enhanced version. Price wise this (and the base Streamline model) sit a little above the LHY, but much nearer the LHY than the Phoenix, whilst having the Phoenix in their sights performance wise. Pricing in AUD. It'd be fascinating to compare the two, or three, which I may well end up doing if funds and my friendly local Phoenix owner (to whom I've now returned it) permit...
https://www.stereonet.com/forums/topic/615006-new-enhanced-usb-reingen/
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