Ndx2 vs nDac

Hi everyone,
I have just replaced my second-hand ND5 XS with a brand new NDX2.
The previous configuration was ND5 XS + nDAC + PS 555
The idea now is to connect NDX2 with PS 555 and remove nDAC.
I did it and it sounded very good. Full details on high frequencies. I only noticed that the bass was less deeper and fuller than in nDAC.
So I connected the NDX2 to the NDAC via S / PDIF (PS555 still connected to the NDX2) and, to my deep surprise, it seemed better to my ears.
Deeper bass, full body, more pleasant!!
So now I’m very undecided whether to leave this configuration, or whether to reconnect the PS555 to the nDAC as before.
Has anyone had similar experiences?

Interesting. By default the Ndac and 555ps was the ultimate upgrade for the NDX.
With the reworking in the NDX2 on its transport platform, it might well have the edge having the ps to itself, and taking out the Ndac. Only one way to find out.

If you are going to keep the NDAC (or any other separate DAC) you might have saved yourself quite a bit of cash by getting an ND5XS2 rather than an NDX2, which has the same streamer board. Of course, the PSU would then have to go on the DAC.


My idea was to buy NDX2 to remove nDAC, but listening it connected to nDAC I’ve discovered it sounds better. Of course that’s my opinion.
So I need to connect PS to nDAC

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Your findings are interesting but perhaps not so surprising. We know that the nDAC is quite sensitive to the quality of its SPDIF input. We also know that the NDX2 has a high quality SPDIF output. And we know that the internal DAC of the NDX2 is not necessarily much better than the nDAC.

If you prefer the nDAC to the internal DAC of the NDX2 (even with PS555!), I would at least try to put the PS555 on the nDAC. I would expect NDX2 + (nDAC + 555PS) to sound better than (NDX2 + 555PS) + nDAC.

But I use a (bare) nDAC fed by an Allo DigiOne Signature and I have noticed that powering the DigiOne with good power supplies (I use UpTone Audio JS-2 and LPS-1.2 for the RPi and for the “clear” power inputs, respectively) has a perceivable impact on the sound quality.

Thus, I would not be very surprised if you find out that (NDX2 + PS555) + nDAC sounds better in your system than NDX2 + (nDAC + PS555)!

No matter what you do, please report your findings!


Could be worth trying the NDX2 + ps into the Ndac, then the NDX2 + ps on its own. The Ndac may well be a bottleneck - or give a different less favourable rendition. Be sure to try all options and please report back with your thoughts.

Another possibility is that the NDX2 needs some time to “bed in”. In order to check this possibility, you should probably use the internal DAC of the NDX2 for a while. I understand that, when the NDX2 is used as a pure transport, (part of) its DAC board is not powered.

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I understand that this is what the OP did before realizing that he prefers the (NDX2 + PS555) + nDAC combo to the NDX2 + 555PS that he was planning to adopt.

I’m trying now to use NDX2+PS555 to see whether the sound improves by using it.
I will do it for some day and then check again this configuration vs. NDX2+PS555 + nDAC.

I’ll do it

The Naim DAC has the same DAC chip, analogue filter and i2v approach as the ND555 and NDS. It will be likely more insightful and superior to the NDX2 analogue out. As you say the Naim DAC has a strong low end performance.
I suggest you configure to suit.
The advanced NDX2 digital transport and streamer front feeding the NDAC/555PS will likely be sonically appealing… and putting the toe in to higher end Naim.
Albeit with NDX, I ran that combo for a number of years and really enjoyed it for many styles and genres.


Agree re the bottom end on the Ndac. The 555 ps gives massive soundstage and grunt

Fed with a decent transport( I use the Simaudio Mind 2 ) its a great source. The Super Lumina Din Din gives a good uplift as well

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If the OP is just using the Naim as a digital front end/ transport, then why not just use a ND5XS2? I didn’t think there was a lot of difference between the front ends on Naims cheaper streamers?


You have the control and display features which are quite extensive on the NDX2 and ND555. but sure if those usability aspects are not important, the powersupply advantage of the NDX2 over the ND5XS2 although real will be relatively small.
I chose the NDX2 over the ND5XS2 for exactly those reasons. Better usability, the display (which is superb) and subtly better digital out because of the larger PSU, but perhaps I’m fussy?
The ND5XS2 is a cracker, especially if you use its analogue output… it’s focus was sonic performance over anything else for its price budget… hence why other areas such as usability and control are slightly compromised.


After testing several configuration:
NDX2 + 555PS
NDX2 + 555PS +nDAC
NDX2 + nDAC + 555PS

I ended up that NDX2 + nDAC + 555PS is the one that sounds better to my ears.

I have to say that NDX2 + 555PS sound improved a lot after first days. So it was useful to let it play for some days and after 1 week there was no much difference between NDX2 + 555PS and NDX2 + 555PS + nDAC

But when I changed to NDX2 + nDAC + 555PS I still felt that bass were deeper and sound was fuller of details.

So I’ve just decided to stay with this configuration.


Very interesting! Thanks for doing this.

Adding a 555ps to my NDX2 completely transformed it.

There’s only one question left:

Would this be the ultimate - NDX2 + 555ps partnered with NDAC + 555ps

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Likely, but 4 boxes!!! Guess it’s fun to dream

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Yes, a bit better.
But ultimate source, no.

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nbpf, the latest dietpi update seems to have made GMrender unable to start on my allo digione, I am kind of losing patience with this device. RPI audio isn’t all that user friendly as it seems.

it really isn’t worth all the hassle? I have a google chrome cast audio which is equal in sound quality, much cheaper and works flawlessly.