Lumin U1 Streaming Transport Review

pricing is a problam in honk kong sell for 28500 hk$ which is 3700 us$

Nice write up!  I especially appreciate a bits is bits guy acknowledging that it is not always the case, and also like seeing China come in with an audiophile-level component.  Cheers!

Why call it a transport?   #confused

Firstly thanks for your review.  I think software navigation of playlists is a big boon once one acclimates to it. 

It seems odd this unit serving up bits could be responsible for the difference in sound you describe.  And that the differences would remain the same when you change how the devices are connected to the DAC. 

Maybe a topic for elsewhere, but when I primarily judged sound quality using subjective listening impressions, the strength of the differences heard seemed greater when I auditioned something new with other audiophile friends present We seem to hear the same differences.  My level of certainty was much greater after such session. I think it is something of the Clever Hans effect we have on each other.  In time errors began to make me question this methodology.  One I remember is getting a rather expensive for the time digital cable.  Inviting a few friends over.  We listen to the old one and then the new one.  Finding agreement the new one was a considerable benefit and largely agreeing on what those benefits were.  After a half hour we wanted to hear the old one again.  At which point we discovered that while the new one was plugged in we didn't ever switch to it (old one was coax, and new one AES).  We had been listening to the same old one the whole time.  By then two of the people present were already discussing ordering the new cable up because it was such an obvious improvement.  One was wondering if AES was simply better more so than the cable in use.  To then only find ourselves with a bit of egg on our collective faces. 

No comparisons, no decision.

Well if the SPDIF is used the clock has to be recovered.  How that is effected by the Lumin will depend somewhat upon the device doing the recovery at the DAC end.  If USB output is used, the clock of the Lumin isn't used.  So no bits are bits logic isn't archaic. 

If there is a different sound via USB output, and that difference is the same over SPDIF, it becomes something odd that doesn't make very good sense in a straightforward manner. 

Regarding the "mandatory use" of the Lumin app to drive the U1, it would be interesting to know if, when the unit is used as a UPnP/DLNA renderer, a non proprietary app like BubbleUPnP can drive it. Could you test that ?

5 hours ago, NOMBEDES said:

Why call it a transport?   #confused

Because even though it doesn't play discs, like a transport it plays digital files and provides a digital output to a DAC's input.

“I'm firmly in the “bits-is-bits” camp when it comes to talking sound quality from what is essentially a purely digital signal.”

Arrrrrggghhhh!!!

(closing this page on my iPad and leaving the remainder of this “review” unread....at least for now)

57 minutes ago, LowMidHigh said:

(3)
Upgrading the power supply of the U1 Mini to LPS will boost the performance close to the U1 level. sBooster and Plixir sell such kits, and they'll set you back $500 to a $900--overall, much more economical than U1. In essence, those kits reduce electrical pollution and thus jitter.

(4)
The U1 direct competitor is ARIES G2, which has lower jitter and better construction, including dual LPS driving separate circuitry boards, galvenic Isolation, suspension footspikes and a uni-chasis. All that for 2/3 the price. If one can live with only iOS support, the G2 is the wiser option.

(The U1 benefits from a BNC output that the G2 is missing, but that's not enough to tilt the balance. Regardless, if possible, one should use AES)

Comments to (3)

The two mini Lumin variants have a single output SMPS to drive the whole system. Yes, you can buy a linear supply to fit out, provided the regulation is such that over voltages do not occur.  Warranty is then a tricky issue. All other models have separate power supplies in their own enclosure and have dual linear voltages from two transformers for analog and digital circuits. 

Comments to (4)

Before purchasing the U1, an audit was made of the Aries G2 as alternative. What put me off purchasing that unit:

a) The G2 iLink is useful only with other Auralic product

b) Several users reported bugs with the on screen display artwork or other details relating to the screen on the Auralic support forum. The conversations went on for too long I thought and a fix was underway, but needed more time. I would have expected software issues like this to be well put to bed with limits (?) placed on metadata for example. The bugs were on production machine released 10 months after they were officially released for sale.

- A quick scan of the support forums of both camps will reveal which site has less user problems, the site a AS (CA) is example.

c) There's different methods for galvanic isolation, some work, some don't.

d) The U1 is also a single block aluminium body, with footers, so don't see advantage in construction, since both are similar.

As for pricing, there's room to negotiate in a civil manner directly with the suppliers, the sticker price isn't the final outcome.

9 hours ago, André Gosselin said:

Regarding the "mandatory use" of the Lumin app to drive the U1, it would be interesting to know if, when the unit is used as a UPnP/DLNA renderer, a non proprietary app like BubbleUPnP can drive it. Could you test that ?

The use of Lumin app is not mandatory for playback control - it is only required for setting change and firmware upgrade.  Lumin is OpenHome, UPnP compliant and Roon Ready, so you may use Linn Kazoo, Bubble DS Next, Aurdirvana, JRiver, etc. or Roon for playback control.

It is even possible to use Audirvana or Roon to upsample music to DSD512 to be played by Lumin X1, T2 or U1 (with a Linux native DSD512 compatible USB DAC) via network.

11 hours ago, NOMBEDES said:

Why call it a transport?   #confused

We call our Ethernet-connected DAC with analog outputs "network music players".

We call our Ethernet-connected streamer with digital outputs only "network music transport".  To me a transport means "digital output only".

52 minutes ago, emcdade said:

Interesting what you noted about the imaging popping out more in front of the speakers when called for.

 

I notice the same thing with the T+A DAC 8 DSD when ran in 512 DSD mode.  The soundstage expands in every direction, including forward, with its single bit DSD converter vs. it's traditional PCM Dac.

 

Is this because it's pulling more detailed and accurate phase information out of the recording?  Or is it just some sort of distortion?

 

I have no clue and limited knowledge on the matter, but I do know that i quite enjoy it.

Yes, this topic has intrigued me as to how to determine what causes a great image, but I do know what can stuff things up.

Logically, if the timing between channels  is 'just there', the image from the speakers will be very good, let's say what the engineer worked out for the recording. From there, its all downhill.

When auditioning USB cables of different varieties, the image tended to tank and be mono-ish, with no sparkle. When using a plain USB cable, there was hardness in the sound as well. Some gadgets or cabling improved matters, so the inference is, that the transmission from the source to the DAC contains artefacts that ruin the sound stage.

DSD512 may have such a sample rate that it could mask the noise, or modulate the noise, so it's not audible? I've tried various sampling rates to DSD256 and was not really enamoured with the results, but each to their own taste.

The U1 at home plays straight to coax up to 192, then conversions from DSD are completed by Roon in multiples of 48/44.1. That signal is so pure, it's 97% of what the SACD player can reproduce, including imaging. Depending on the recording, the SACD player can position instruments forward, bottom right or left, the U1 comes close but not quite there. If AES3 is chosen, might get there, but the DAC accepts coax digital only.

But for now, if you have a DAC you're very happy with, then the simplest transmission is over Ethernet to digital, which the Lumin U1 does very, very well indeed. Less bits in the chain, the less chance of crud entering the chain.

1 hour ago, emcdade said:

Interesting what you noted about the imaging popping out more in front of the speakers when called for.

 

I notice the same thing with the T+A DAC 8 DSD when ran in 512 DSD mode.  The soundstage expands in every direction, including forward, with its single bit DSD converter vs. it's traditional PCM Dac.

 

Is this because it's pulling more detailed and accurate phase information out of the recording?  Or is it just some sort of distortion?

I personally believe clock jitter can affect imaging.

9 hours ago, André Gosselin said:

Regarding the "mandatory use" of the Lumin app to drive the U1, it would be interesting to know if, when the unit is used as a UPnP/DLNA renderer, a non proprietary app like BubbleUPnP can drive it. Could you test that ?

Yes, many LUMIN owners use a variety of apps such as BubbleUPnP to control LUMIN. LUMIN is fully Openhome compliant. Of course, many owners of other hardware also use the LUMIN App too.
For the actual LUMIN Settings (things like logins for subscription services, upsampling settings, display brightness, etc) you will have to use the LUMIN App for either iOS or Android, but not necessarily for playback.

I use another brand of App to occasionally control LUMIN from my PC for example.

6 hours ago, One and a half said:

 

Comments to (3)

The two mini Lumin variants have a single output SMPS to drive the whole system. Yes, you can buy a linear supply to fit out, provided the regulation is such that over voltages do not occur.  Warranty is then a tricky issue. All other models have separate power supplies in their own enclosure and have dual linear voltages from two transformers for analog and digital circuits. 

 

Comments to (4)

Before purchasing the U1, an audit was made of the Aries G2 as alternative. What put me off purchasing that unit:

 

a) The G2 iLink is useful only with other Auralic product

 

b) Several users reported bugs with the on screen display artwork or other details relating to the screen on the Auralic support forum. The conversations went on for too long I thought and a fix was underway, but needed more time. I would have expected software issues like this to be well put to bed with limits (?) placed on metadata for example. The bugs were on production machine released 10 months after they were officially released for sale.

- A quick scan of the support forums of both camps will reveal which site has less user problems, the site a AS (CA) is example.

 

c) There's different methods for galvanic isolation, some work, some don't.

 

d) The U1 is also a single block aluminium body, with footers, so don't see advantage in construction, since both are similar.

 

As for pricing, there's room to negotiate in a civil manner directly with the suppliers, the sticker price isn't the final outcome.

Thank you for commenting. Allow me to relate.

Warranty is then a tricky issue.

Those changes are easily reversible and cheap to do, especially if you're handy with the soldering iron. 

All other models have separate power supplies in their own enclosure and have dual linear voltages from two transformers for analog and digital circuits. 

I haven't seen any reference that each external PSU powers a different board. But learn and live.

The G2 iLink is useful only with other Auralic product

The G2 iLink isn't a channel to input anything into the ARIES G2. It only facilities streaming from it into the VEGA G2.

(The latter's streaming capabilities are more limited). So as a stand-alone streamer, your point is actually moot. 

Several users reported bugs with the on screen display...

I believe AURALIC has outsold Lumin by a fat margin, given the relatively affordable prices, so you'd find more users with issues in general. As a rule, every vendor in the field has occasional software/hardware issues, so customers always take a chance when they take the plunge. But if Lumin is truly more robust than AURALIC, then more power to them and to you. And I write that with sincerity. 

There's different methods for galvanic isolation, some work, some don't.

What's your point? That AURALIC galvanic isolation is questionable? You need to substantiate that assertion, or be accused at merely floating vague innuendoes.  

The U1 is also a single block aluminium body, with footers, so don't see advantage in construction, since both are similar.

Lumin hasn't made any claims its chassis blocks EMI. Maybe it does, then I'll be stand corrected again. The G2 has suspension footspikes that dampens a certain range of frequencies so the oscillators aren't disturbed. I didn't see such feet on the Lumin.