Atc smc40


That’s exactly what I had for the front end, but DR version[252/300) .I have never had a second thought ( which I thought I might have, ), the 40A are so good, also they are just being fed from my Auralic Vega 2, with the plain old studio mic cable I got from Dave at ATC when he installed them for me.I don’t feel the need to experiment with mega price cables,
Go and have a demo I don’t think you would be disappointed.
One point , however, about bass and room interaction, the only I missed was the bottom octave as I had Dynaudio contour 3.4s speakers previously, so to my ears the ATC, was a bit bass light, being an IB design. So I now have a REL S5 SHO sub connected, and that was the final piece to the puzzle, fabulous bass to die for !!


I’d probably keep Mutec in front of Mytek or any other dac/preamp since it’s about as good as USB bridge can be with proper galvanic isolation and reclocking. Source really does matter.

Grahamhifi you’re killing me… The passive 40 still sings beautifully. Got to appreciate the weight and dynamics it offers. Actives would take this a step further I believe.


The passives are amazing for sure, but the actives are soooooooo much better IMO.


I’m using spdif, which is galvanically isolated. I believe the first generation Hugos have won some accolades on this forum with that input. The point i’m trying to make is that dac transport matters. I compared the dcs network bridge to my then nd5xs ( on my Hugos) , and the difference was so great that i had to sell my longest tenured naim box. If you don’t believe transport makes a difference , you could read the dcs network bridge review from Rafael Todes on Hifi+. The review was done with a dave which is advertised as immune to source jitter.

Running the Bridge through my Chord DAVE, with a Chord Signature Digital cable, through a VAC Sign ature preampand VAC Phi 200 monoblocs, driving B&W802d2 speakers, left me initially –
having heard Solti conduct Mahler’s 5th Symphony on Decca – with a pang of guilt.
Why had I not heard it sounding like this before in my system? Had I not been feeding my mighty
DAVE DAC previously with a high enough quality source?

Or you could try something different from your perfect source, which seems to be the only unquestioned component in your system , and see by yourself.
If your sentence on active 19s was something like “They were ruthless of poor sources”, i would have agreed.


Did you change straight from passive 40 to active?


No. From passive Dynaudio 3.4, driven from 252/300DR, but I had a demo, of 40 passive,and the actives easily beat the passives driven by 252/300DR.


Well that’s encouraging. I run my passives with SN2 so it should be a substantial upgrade then. What bothers me most is the huge change in front end I’d need to do. I’ve had Naim DAC as my source since 2011 and it’s still just a really good source. Also my main idea behind this demo was to cut down the box count so replacing SN2 with 202 or 282 only adds more boxes (NAPSC). 272 is only option in Naim lineup and I think it’s not on par with nDAC. Difficult decision!


It takes a leap of faith for sure. I’ve been Naim for 15 years, so huge decision to change from 252/300/ndac/ndx, initially tried 272 into 40A,which was great but Auralic is much better , don’t regret it for a second, and still have loads of respect for Naim, but there are great alternatives .


Well you have very similar route then, but you moved from much higher on the Naim ladder. Auralic is sure an interesting manufacturer but G2 is out of my reach for now at least. It’d probably have to be Mytek for now and maybe upgrade the front end later on.


I’m simply following advice from Chord Electronics and Rob Watts. If they use a battery powered laptop as DAC transport then that’s good enough for me. After all, they did design and manufacture the DAC.

We all have different tastes. In my room with my setup I simply preferred the 40s by some margin to the 19s. I perceived the 19 actives to be the brightest and most unforgiving of all. The 40 actives the best of all, and an easy listen. I didn’t think there was a massive difference between 40 passive with P1 and 40 active.


Hi, actually I don’t believe the SPDIF input on a Hugo is galvanically isolated, however the SPDIF output from Naim streamers is, and so makes a perfect coupling.


Certainly when I had a Hugo, I found that different renderers could sound different. Whether any of that was due to differences in ground plane modulation i) from ND5XS direct to Hugo, or ii) from Mac Mini running optimised Audirvana via Gustard U12 to Hugo, or whether there are other causes of differences, I do not know.

I haven’t yet tried to compare anything different into Dave, which has the greatest attention to blocking RF of any Chord DAC, possibly most available DACs. I think one check that could be done by anyone running a battery Mac into Dave would be to compare different bitperfect software renderers (with their different system setups) to see if there is any difference (the battery operation ruling out RF ground plane modulation). Of course, it needn’t be a Mac.


I was not aware that the SPDIF output was isolated Simon,thanks for that info.Do you think it would be a waste using ferrites on this cable coming out of my NDS into a Chord Dac?(TT2)


Probably if I am honest.


The main causes of difference is down to the SPDIF transport clock stability. This should not be confused with sample clocks and jitter, or ground plane noise which if galvanically isolated unless at RF is going to be largely impeded, I am referring to specifically the SPDIF link layer framing clock. Any instability in this clock will create frequency modulation and intermodulation artefacts (this is how FM radio works…). These artefacts will couple into the receiver… say a DAC … as different noise frequencies. This ultimately will affect the DAC performance, although careful EM screening and decoupling can mitigate, but as we hear it never goes away completely.
This is why quality transports go to great effort to use ovens and other stability methods around system clocks.


You refer specifically to SPDIF. Would the same apply to USB? If memory serves, Rob Watts uses his standard MacBook source via USB, preferring that input to Dave, and his focus seems to have been substantially on preventing ground plane RF modulation. I haven’t followed all his explanations, so I don’t know if he has said anything specific about USB clock stability and blocking associated modulation (if that is possible).


USB has its own challenges some of which are mitigated to some extent with USB 3, but there is more noise potential with USB as in many senses it operates not dissimilar to a subset of Ethernet, and of course the PDU clock sensitivity is the same as for SPDIF… it just the link layer is implemented differently, and SPDIF is effectively connection less.
This is why in some circles SPDIF, AES/EBU and i2S are preferred as they are less prone to digital noise due to being a simpler protocol.
None of these aspects I describe are specifically linked to RFI or ground plane modulation passing from one device to another… and Rob once told me with DAVE his team were not able to identify and measure any effective ground plane modulation in operation… which is not quite the same as saying there is none… but it will be below the threshold of their measurement tools.


Running a MacBook on batteries negates any issues that might come from a mains connection. Having galvanic isolation on the USB will also help. The new MacBook is highly energy efficient and very different from the noisy laptops and desktops of the past. I can’t tell any difference between iTunes, Roon, or JRiver running bit perfect at 16/44. I playback directly from the MacBook internal SSD drive, other than the DAC, nothing else is connected to the MacBook. There are no fans, noisy toroidal transformers, or any moving parts. Jitter and RFI/noise are a non issue. Check with Rob Watts, he’s measured them. It simply delivers a load of bit perfect 0s and 1s without adding a load of electrical noise. It’s the noise where you will hear differences. Noise from ethernet cables connected to your router which is connected to your mains and telephone line etc.

It’s as smooth as a baby’s bottom with zero listening fatigue. That’s the best test at the end of the day.


noise in a source is an excitation , and this noise will affect the receiver
in non trivial ways ( even if it can be calculated by dedicated computer programs). It will induce
parasitic currents at different locations , this will affect the analog stage performance in a
dac. Have you wondered why soldiers break stride on a bridge ? What happens in the electrical domain is very similar to what happens in the mechanical domain. A small excitation can have major consequences ( so to speak).
no matters what they represent in terms of 0s and 1s.

A general purpose computer is much more noisy, than a dedicated high quality streamer. A basic test proves it


That all sounds like audio hypochondria to me.

If that’s true why does Rob Watts not use a dedicated high quality streamer for his critical listening?

In addition, if noise was an issue then why not hear any difference between USB and optical?