DSD128 and 384kHz on Lumin D2


#1

Hi,

I have a home demo setup with the D2 in a couple of weeks and am just doing some reading around - it will be connected to Roon as an endpoint over Ethernet. Really looking forward to takkng it fir a spin. I see the specs quote DSD128 and 384kHz but am I right in thinking that this would be downsampled as the Wolfson WM8741 tops out at DSD64 / 192KkHz? So, if upsampling in Roon, it would make no sense to use the higher sample rate?

I see that chip has been around a good 10 years - is that something I should be cautious about given I wouldn’t want to be upgrading again any time soon?

Thanks!


#2

WM8741 datasheet top out to PCM 192k limit due to fixed over-sampling digital filters but as for DSD, it may go higher than DSD64 which is directly coupled to the switch capacitors array analog conversion, but this is not guaranteed by design.

If up-sampling in Roon is important to you then you may want to consider Lumin X1 which uses the latest ESS Sabre DAC.


#3

Many thanks @MusicFidelity - I’d be astonished if I could hear the difference between 192KHz & 384KHz…I was more checking that I’d understood things correctly in terms of implementation. Perhaps @wklie might chime in with regards to your comment about the DSD implementation.


(Peter Lie) #4

WM8741 indeed tops out at DSD64. Playback of anything higher would require conversion. If you like the sound of DSD, set Roon DSP engine to convert everything to DSD64.


#5

Thanks @wklie - I haven’t had the option to try before but look forward to experimenting. From what I’ve read in your posts elsewhere I should turn off Spotify, Airplay and the digital out if not using - anything else you’d suggest for the demo, apart from lots of listening?

At the moment I have both RCA and XLR connected on my existing DAC (to my main amp and headphone amp respectively). I understand this works but isn’t recommended with the D2 - can you give any more info as to why this impacts sound quality? Perhaps the risk of interference from one device? If one of the devices is turned off presumably it’s then not an issue?

Many thanks.


(Peter Lie) #6

This degrades the SQ from an engineering point of view, even if one of your amp is not powered on, due to the way the X1 / S1 / A1 / T1 hardware is designed. D1 and D2 are a little different because they lack the Lundahl transformers - I need to discuss with hardware guys and recheck whether this would be significant for D1 / D2 or not. That being said, I’ve never received any user report of how much or little this degradation is for any Lumin model.


#7

Many thanks - I guess I’ll try to listen for a difference (I may also play around with this a bit more in my existing setup). Will be interested to hear what you get back from the hardware folk.


(dan baldwin) #8

I think you will be pleased with the sound and functionality of the D2. I don’t think there is a better streamer/DAC combo out there for the price. I’ve had one for several months. I had the money and I wanted a bit better sound so I replaced the D2 with a streamer/DAC that cost at least four times as much. I liked the D2 so much I kept it as a backup just in case. I blind tested the D2 against my new DAC and the new one was only slightly better. Please follow up when you get to listen to it, I’d be interested in your opinion.


(Peter Lie) #9

With a simultaneous connection of XLR and RCA, the theoretical SQ degradation is nearly negligible on D2, as compared to other models.


#10

Thanks for taking the time to check this @wklie. This level of customer engagement is one reason I’m looking at the D2 in the first place.


#11

Thanks @dan_baldwin that’s good to hear, it’s coming in around 10 days so will feed back once I’ve had enough listening time. I’m rather hoping I don’t like it, but perhaps that’s a healthy starting point :wink:


(Greg Slonim) #12

Hi @wklie,

I have recently auditioned a D2 and really liked the sound on my PrimaLuna Dialogue HP tube amp with Focal 936 speakers. I also liked your software. I did, however, felt a bit of edginess in the sound, it was a bit sharp/digital(?) in nature. This is a fairly new unit and I am not sure how long my dealer had it play (if at all).

I have several questions in regards to D2 as well as T1, if you do not mind.

  1. Since T1 has a different analogue implementation (as you mentioned above), is there a discernible sound signature difference between D2 and T1? After all, a T1 costs almost twice what a D2 costs.

  2. If I were to use an external DAC (say, a Holo Spring), and wanted to have Lumin’s software infrastructure, do you think that a U1 Mini would be the best choice? It seems to have many digital out choices.

  3. If I were to use a U1 Mini and its USB output into an external DAC, do you think I’d benefit from a DDR? There are many of those types of USB devices, such as KTE-SU1 and many others.

  4. There are a lot of streamers on the market; many people refer to SoTM, Rendu, etc. Do you mind sharing what makes Lumin different from them?

Many thanks for your input.


(Peter Lie) #13
  1. Please burn in the D2 7x24.
  2. T1 is warmer and more analogue.
  3. To use an external DAC, U1 MINI is preferred to D2.
  4. Unless you really want to use I2S output, I’m not sure how beneficial that is. I remember a customer using U1 with SU1.

(Peter Lie) #14
  • I’ve read reports that some people find that AES sounds better than USB in their setup. If one uses a DAC like this one may want to try using AES.
  • Lumin never charged users for firmware upgrade, not even MQA decoding, let alone regular updates
  • Although this is more relevant for non-Roon users, some people buy Lumin products because of Lumin app. We also have official MQA Core decoder when playing Tidal Masters or MQA CD, especially when not using Roon.
  • Lumin is certified by Chord Japan to be compatible: https://www.chordelectronics.jp/products/choral-range/dave/
  • Feature differences aside, it’s best to contact a Lumin dealer to see if you can audition it with your setup

(Greg Slonim) #15

Thank you for the write up, @wklie.


#16

So, I really didn’t want to like the D2…it’s expensive (to me), uses SMPS, aging DAC chips, has no digital inputs, no bluetooth, limited scope for upsampling and no direct NAS access.

However, I genuinely cried during the first track I listened to…for me it really was that good at conveying the music. Vocals and instruments all seem to just sound more present, 3 dimensional and organic, drums and guitar in particular sound as I believe they should. The background against which they appear also seems somehow darker and more silent. The rest of my system, which lusts longingly for a future upgrade to Amphion speakers and a Hegel amp, has no business sounding this good. My headphones, connected via the balanced outputs to an Arcam rHead, also sound completely upgraded. I’ll make a decision over the weekend after some more hard-headed comparison but at this point I’d be very surprised if I don’t choose to keep it.

Some asides - the build quality seems very good to me and the very slight audible hiss from my tweeter at rest is much reduced from my previous setup (even when the DAC was on a good LPS). I’m not a fan of the Android app on my tablet, certainly not on first impressions (makes the Bluesound App look good imo) but I don’t care about that. Much to my surprise, I also so far don’t really like the effect of upsampling on it (either on the D2 or when done via Roon) - it seems to lose a little detail. Perhaps @wklie can clarify but as I understand it upsampling must still be happening in any event inside the DAC chips? Not quite sure why I prefer it that way. I do though find converting to DSD good for headphone listening - makes it a little more laid back.

@wklie don’t suppose there’s any plans/scope for a USB Bluetooth dongle? The use case for me is two good, firstly friends and secondly surfing Roon and coming across new artists who can only be previewed on Bandcamp or similar.


(Peter Lie) #17

The WM8741 is indeed an oversampling DAC chip. If you try Roon upsampling, make it DSD64, and there are a few options to try.

I’m afraid there is no plan to support USB bluetooth.

I’m glad it sounds good to you. Please burn it in 7x24.


#18

Thanks @wklie, I’ll have more of a play with the various DSD settings - the choice was a bit overwhelming (my other DAC didn’t support DoP) so I went for 7th Order CLANS as a start.

I’m always a bit sceptical of burning in but I have been doing so - the first 24hrs did indeed make a marked difference.


(Greg Slonim) #19

Hi Peter, thanks again.
Question about T1’s LPS:

Does T1’s LPS have dual windings in its transformer? In other words, can a US-versioned T1’s 110v mains LPS be changed to take 220v ?

Cheers, Greg


#20

Thanks for clarifying, Peter - that’s a real shame though. Whilst at one level I admire its dogged determination to do one thing and do it well, a couple more features would be very welcome. Similarly, are there any plans for network file access? Whilst this shouldn’t be necessary with Roon, it’s always good to have a fallback position if something breaks, without having to setup something like minimserver. Frustrating that this is available on much cheaper streamers but not the D2 (even if the sound has now won me over :wink:).