Nd5 vs ndx into ndac

I'd say either solution is rather extravagant because in each case you're buying an expensive DAC and not using it.  How about a Mac Mini or laptop as a source?

I would add a PSU to the Naim DAC as a first step.

I don't think I'll be alone with that advice. 

How do you feed your Naim DAC today? 

It depends if you want to replay 24/192 music, s/pdif is not supported over 24/192 so you would need to play these to the analogue output of the nd5xs or new (24/192) ndx.

Maybe im reading your post incorrectly but.... 24-192 works over spdif.  Files OVER 24/196 resolution might not but Im not sure that is what you intended to day.

Related to the thread I started about the possibility of adding a streamer between my uServe and nDAC, a well-respected dealer advised that the first step should be adding a PSU to the nDAC.

Thanks all.

I am currently using a squeezebox touch as the streamer.  Unfortunately the library management is very poor and heard the rumor that ndx / nd5xs will be supporting AirPlay (which itunes is way better in library management).  That's why I am thinking about the upgrade. Otherwise, the next step is definitely a xps or xp5xs... Thoughts?

iTunes should have a beter library management than LMS????? This is simply not true!

Update to the latest version of LMS. The best thing about LMS is that it doesn't mess around with your files like itunes does.

AirPlay has a lot of compression I think.  Is that correct?  So bad way to stream for SQ. 

Yes correct, I must have read that wrong someplace, s/pdiff will do 24/192.

Strictly speaking S/PDIF is only formally specified upto 24/48. However it can be commonly used up to 24/192 by the receiver reading the data rate and calculating the sample rate from the frames. I see no reason why therefore higher rates could not be used. Certainly the transmission method would support data rates significantly higher. Its probably due to a lack of higher specified trasceiver chips than anything else, but that might change if there was a demand

Simon

Well, I did that last week as part of my upgrade.  NDX/nDAC vs ND5 XS/nDAC.  Using both XPS and 555PS to power the NDX (as recommended by Cymbiosis during the demo).  I'm getting the NDX /555PS (I already own nDAC), so you can guess what my opinion is.

Hi Zinger -

AllenB also posted an opinion on NDX versus ND5 XS as a source for the DAC:

https://forums.naimaudio.com/di...59#11281028948757959

I purchased the NDX after hearing it's digital output compared to my PC music server's RME 9632 card.  At the time, I was convinced that there could not possibly be enough of a difference among digital outputs so as to warrant such a purchase.  I was convinced that the Naim DAC was the great leveler of digital sources because, at the time, I could not hear a significant difference among the sources I had tried (PC server, Oppo BDP-83, and a few others).  But, seeing as how the NDX was brand new at the time, my dealer sent one to me to listen to (along with the pair of Ovator 400's I had specifically requested to try).  Well, much to my surprise, the speakers replaced my Harbeth C7's, and...

It has been a 9 month long NDX love affair!  I re-purposed my PC server (sans RME 9632) as a UPnP server running Asset, and purchased an iPad to run N-Stream.  The end result has been remarkable sound quality and perfect reliability.  During a normal week at home, I have 4-to-6 late night opportunities to listen to music for an hour or two.  So far, not one single listening session has been sacrificed to debugging.   I now know that I can count on my NDX to be available when I need it.

Allen's system is a bit above mine, but still, I am pretty sure I would have made a similar evaluation of NDX versus ND5 XS had I the opportunity to compare them side-by-side.   That opportunity has now slipped away, for like he and several others, I am now eagerly awaiting the release of the NDS.   If it trumps the NDX->DAC combination, I plan to be among the early adopters ("early", of course, not quite having the same meaning on this side of the Atlantic).

Sorry to ramble on, but as you can see, I have very strong positive feelings about what Naim is doing in the Network Player space.  I wish others all the best with their Linn or Weiss or whatever decisions, but I've seen and heard enough from Naim to know that it is what's right for me.

ATB.

Hook

Hi

I too compared both NDX and ND5XS into the DAC and to be totally honest, I couldn'd tell any difference whatsoever through my revealling ATC active set up on home dem. So for me, the 80% cost difference couldn't be justified.

However, I didn't use any extenal power supply - which may be the deciding factor (?)

Incidentally, as far as I am aware the outputs on both NDX and ND5XS are exactly the same

Naim confirm that the differences between NDX and ND5XS are as follows;

Sockets (DIN and RCA)

The ND5 XS uses PCB mount sockets and the NDX has hand-wired chassis mount sockets for microphonic isolation.

Op-amp grade

The NDX uses higher performance op-amps for the filter stages

Resistors

The NDX uses matched though hole resistors and the ND5 XS uses SMD resistors in the analogue stage. The NDX resistors are also raised from the PCB improving microphonics for better sound quality.

DSP

Both use the naim modified Butterworth 16x IIR digital oversampling filter in the SHARC with 40 bit floating point math and bit perfect RAM buffering for ultra-low jitter.

Capacitors

As per the resistors the NDX uses through hole capacitors for all audio critical parts, the ND5 XS uses high quality SMD parts and the occasional through hole part.

Isolation

Both have complete optical isolation suing 50Mbs optocouplers

Transformer

NDX has higher capacity transformer than ND5XS

Hope that helps

Hi Mr. Frog -

IMO, everything makes a difference.

From the DAC perspective, I think that most of us have finally gotten around to the realization that digital sources, be they network players or cd transports, still matter.   When the DAC first came out, I was convinced by reading the white paper that all of these differences had been erased, and all that was needed was a "decent" S/PDIF output.  Too many people with revealing systems have now heard otherwise, and agree that this is simply not the case.   And those with ultra-revealing systems seem to be agreeing that this is also not the case specifically with the ND5 XS and the NDX.   There are several possible explanations, all having to do with noise transmission of some sort:  through the S/PDIF cable, back through the mains, or even through the air!  RFI, EMI, mechanical vibration...don't know which explanation best suits this particular comparison, but I know that everything matters, and I know that Naim puts a lot of engineering effort -- both electrical and mechanical -- into all of these areas.

A lot of folks will say:  but it isn't worth £1000!  And I am sure that is true...for them.  But others may make a different decision based upon their own circumstances.

On the receiving end, the DAC and the DAC/XPS-2 and the DAC/555PS are of course very different products, with the latter having the greatest ability to reproduce the finest detail.  If you haven't had the opportunity to hear this for yourself, then you will be in for a huge treat at some point!   IMO, the DAC/555PS is as good as it gets in the marketplace.  Like many others, I've listened to a lot of very revealing digital setups, and I've yet to hear one that, to my ears, betters the DAC/555PS.  In fact, the only other DAC I've been tempted by is the Playback Designs MPD-3, and only because I have a Korg MR1000 recorder and a lot of 5.6mhz DSD files (needle drops that were created at double the sample rate of SACD's).  At the last year's RMAF, I heard this device playing DSD files via USB, and sound was just incredible!  Am still considering a home demo someday.  But again I ramble...!

Of course, everything else in the replay chain downstream from the Naim DAC matters as well, so it is not surprising that the differences in digital output between the ND5 XS and NDX can be heard by some ears in some setups,  but not in others.

ATB.

Hook

Slim yes, but it has a brushed faceplate before the XS was released. So the DAC was designed to be in the Classic Series.

I prefer the NDX to the bare ND5XS (on a NDAC) by a noticable margin.

But a ND5XS + XP5XS combo is very close to a NDX  (always on a NDAC).

Technically most of the differences beween the 2 affect the analog stage.

The power supply has a big impact on the digital output also.

Using both with external power supplies, the difference resumes to mecanics (casing, cable dressing...).

Just like CDX2 vs CD5XS, almost the same electronics...

+1

Ok here goes, I have tried to keep it simple and adapt some examples I have found on the web. I have left RF ground currents in the SPDIF out of it - as I don't see that they are neccessarily Powersupply size related:

1. The Problem:

Powering an electronic circuit is a complex issue. Signal processing circuits vary in their ability to reject interference from supply voltage fluctuations. This ability is measurable and is called the power supply rejection ratio (PSRR). Any interference on the power supply output will be passed into the electronic circuit, at a reduced level, governed by the PSRR of the circuit. For example, if the PSRR is 20 dB, the amplitude of the interference will be 10 times lower than the power supply fluctuation itself (40dB is 100 times lower, 60dB is 1,000 times lower, 80dB is 10,000 times lower and 100dB is 100,000 times lower). Different signal circuit topologies have different PSRR's which can be quite low particularly at high frequencies. When power supply interference mixes with the signal, it masks low-level information and causes inter-modulation with the signal. This destroys the integrity of the music signal. For the highest performance from digital audio and nalogue audio electronics, great care is required in the design of the power supplies to minimise power supply induced problems. Further noise present in a SPDIF transceiver will modulate the clock and produce phase distortion in the SPDIF biphase encoding. This will casue perturbations in the receiving clock transceiver powerlines through the modulation of the powerlines through the receiver SPDIF switching logic. This has the potential of casuing phase noise in the receiver clocks through modulating the powerlines.

2  The Ideal:

To ensure no interaction with the powered circuit, an ideal power supply, should have no output voltage fluctuations under any load conditions, which means that the output impedance should be zero at all frequencies of operation. You can't generate a voltage across zero impedance. Also, it should not allow interference to break through from other sources like the supply line, such as rectifier diode switching, digital clocking and radio frequency interference (RFI) etc via the mains supply. This implies that the power supply should have infinite PSRR of its own power source.

3.  The Practical

Unfortunately, due to the limits of the various power supply design options available, power supply interaction will occur. The level of interaction is governed by the ability of the power supply to approach the ideal performance of zero output impedance, and infinite supply rejection of it's power source, at all frequencies of operation. This means the larger the inducatance and size of the transformer the better the PSRR is at RF frequencuies.

So therefore I maintain a larger transformer has a better PSRR at RF frequencies and therefore less phase distortion and consequential sideband errors to clocked signals which can can couple to modulate sensitive DAC and DSP clocks - which in turn transforms that noise power density from digital noise  to analogue noise at the conversion stage thereby masking low level detail.

Simon

Simon - I was interested in Manu's reasoning.  I think you and I have been round this goldfish bowl before! 

BTW - is a summary of your theory that a stiffer power supply results in less digital output noise from the streamer.  The digital noise is jumping across the nDAC's front-end isolation into the DAC chips and analogue stages?

Noogle, 'tis true we have. But since that first trip and this subsequent one, I brushed up on my powersupply theory - its been a few years, and tried to share my reasoning as above. Manu is free to disagree, my reasoning is only my hypothesis and quite prepared for it to be challanged - but perhaps not on this thread... !!