naim Audio does DXD!

[DSD_mastering]

We just got back from RMAF 2009 and it was great to meet quite a few from here.

This is the fist consumer DAC to do 24/352.8kHz! The naim Audio guys came over to our room and wanted to know if we had any 24/352.8kHz files they could borrow. Being british, of course they wanted Floyd's DSOTM tracks.

The new DAC will be out in a couple of months and and have USB, Coax and thumb drive inputs. Hopefully I'll get a sample to review.

 

[Audio_ELF]

Bruce ...

Is this DXD support via WAV files on a Memory Stick? Thats what I'd been lead to believe. Not that it matters.

 

Eloise

 

[DSD_mastering]

Yes, via memory stick, though it will also do DXD via coax inputs.

 

 

Regards,

 

[Audio_ELF]

Bruce ... are you sure? ... the specs published for the Naim DAC say only upto 24/192 via co-ax SPDIF.

 

Eloise

 

PS. was the DSOTM comment a joke or do they really exist in DXD format?

 

[DSD_mastering]

They assured me that the coax would input DXD via the MADI format.

 

Yes, DSOTM does exist in DXD format.

 

 

 

Regards,

 

 

[jphone]

They have the details on their site

 

http://www.naim-audio.com/products/dac.html

 

they say it does 768K/32bit which makes it one track per memory stick at best :-)

 

[Audio_ELF]

... or at approximately 500MB for a 3 minute track (see Chris' demo downloads on front page), you could just put 90-100 minutes on a £17.99 (from amazon.co.uk) reusable 16GB memory stick ... thats plenty for Sony's preferred Beethoven's 9th...

 

Eloise

 

[Mike in MD]

I estimate that since 24/96 is about 2 gig per album in WAV, then

 

24/352.8kHz is about 7-8 gig per album

 

32/768kHz is about 20 gig per album.

 

my HDs are too small for this.

 

Mike

 

 

[Audio_ELF]

Off the front page ... FIM Demo track at 32-bit/352.8 kHz - Carmen: Habanera Fantasia AIFF 32/352.8 (526.42 MB).

 

According to Wave Editor this was 196 seconds (just over 3 minutes) long.

 

A 16GB memory stick is £18 from Amazon. This will hold approx 32 tracks this long - therefore by my calculation that's 32 times 3 minutes - more than sufficient for a CD worth of music. And 32 and bigger sticks are available so it's not OTT.

 

Now weather we NEED this high quality is a different debate.

 

Eloise

 

[jphone]

I was joking about the track per stick, but if you are trying to be accurate you have to double your estimates since the maximum rate capability per NAIM is double the FIM rate (same bits). And wait for somebody to provide source material that goes that high of course. Nothing wrong if it costs nothing or next to nothing to accomplish, otherwise 44.1/16 is more than adequate for these old ears.

 

J.

 

[Mike in MD]

My numbers are based on the following:

 

16/44.1 CD holds max 700 meg

 

24/88.2 is 3 (=1.5 x 2) times bigger or 2 gig

 

24/176.4 is 4 gig

 

24/352.8 is 8 gig

 

32/768 is approx. 8/3 (= 4/3 x 2) bigger, so 21 gig

 

Mike

 

 

[Audio_ELF]

Mike ... Bizzarely both sets of calculations make sense ...

 

Suffice to say you can easily get a memory stick to fit an album (or two) of DXD (32/352.8) resolution if you wanted.

 

Completely off topic - I found a recipt for a 32MB card for my first digial camera (about 10 years ago) the other day. All I can say is "ouch!"

 

Eloise

 

[Telstar]

768k/32bit are the limit of the DAC chips.

 

[Andrew S.]

Thanks Bruce

I love Naim source gear - amazing stuff. Like Meridian. And dCS.

 

[idiot_savant]

Hi,

 

I've just been through the white paper again, and unless I'm reading something wrong, the Naim DAC may not be as perfect as first seems for 768/32, or 352/24. or less....

Firstly, there's definitely no mention in the spec of anything higher than 24/192 being able to be input on anything but a USB stick, or any mention of MADI. MADI is non-trivial to implement, so I think they would make a bit more of a fuss if it could do it.

 

Secondly, and I can't make up my mind how important this is, the analogue filter used rolls off pretty quickly after 22kHz - this means that the analogue filter will have a very notable effect on any material with content above 20kHz, in terms of level and phase.

 

The above is based on stuff Naim has published ( the spec and white paper ), and obviously not on the actual unit itself - I guess I'm just saying to be careful on basing opinions on an unreleased DAC with regards it playing material at higher res than anything else. I'm sure it will still perform excellently, though.

 

Bear in mind, as well, that the DACs being used ( PCM1704 ) have a 24 bit input, not at 32 bit one...

 

your friendly neighbourhood idiot

 

[Purite Audio]

IS Hi, I borrowed a Denmark AX24 the other week, and chatting to their guy he said the only way to get 352 out of it was to use one of their own Pyramix DAWS , ( they use MADI ) so can any chip accept 352 is it just a question of upsampling?

Regards Keith.

 

[DSD_mastering]

The DAD AX24 will also do DXD via AES3 in quad-wire.

We use both.

 

 

Regards,

 

[idiot_savant]

Hi Keith,

 

the way to think of it is this:

Most DACs ( and I'm talking about the final bit in a DAC box ) have what you might call a "native" sample rate, which is the rate they expect to go at, and the analogue filter after this is tightly coupled with this rate.

For brevity, we'll examine the case of the PCM1704, as it is multi-bit, and used in this case.

 

The PCM1704 itself has a digital filter, so you can input data at, say 44.1, 88.2 etc, and the filter is responsible for converting ( oversampling, upsampling, whatever ) this rate to one it works at internally. So, for a 44.1k input, it will generate 16 DAC samples for 1 input sample. This is how the majority of DACs work - they take an SPDIF receiver chip, and feed the output of this into the input of the DAC chip.

What Naim are doing is telling the PCM1704 to process data at the rate it's given, so in this case, the DAC itself is fed data at 768k ( or 705.6k ), and Naim take care of the filtering/producing 16 DAC samples for every input sample.

 

Now, for higher sample rates, the problem moves from filtering ( generating DAC samples per input sample ) to actually getting the audio from the source to the DAC. For a 768k input, they literally just read a sample from the input and put it into the DAC, but most audio interfaces just don't go that fast - hence you need two or more wires of AES, or MADI, or some other interface to actually get the audio into the DAC.

 

your friendly neighbourhood idiot

 

 

[PeterSt]

Hi i_s,

 

It doesn't seem to matter how many times I read this, but I can't understand. But (please) this is out of the context of this thread. I don't think I need elaboration, but just some other english (try dutch :-).

 

Also (but besides),

 

The PCM1704 itself has a digital filter

 

I sure hope not.

 

Thank you !

Peter

 

[idiot_savant]

Got the PCM1704 mixed up with PCM1794...

 

Peter is absolutely correct- the PCM1704 is typically used with it's partner chip, the DF1704 ( which provides it with 768k/705.6k ), whereas the 1794 has a filter built-in which can be bypassed ( and is a different DAC architecture )

 

your friendly neighbourhood idiot

 

[bordin]

My brain has only 2 GB space left.

 

Maybe it's time to "reformat". ;-)

 

[PeterSt]

Well, one can't have anything on top of his head, and for me it is more easy because I use the 1704. Haha.

And btw, by now I love my filterless operation (doing it in software a 100 times better ... well ... that's what I hear and that's what people tell me : http://www.phasure.com/index.php?topic=935.0;all (skip my own posts))

 

Since my DAC does 24/384 just the same, I was actually quite surpised to see a solution like a memory stick for input, but ... but ... come on, does this ever work conveniently ? Of course, after copying for several minutes you can listen for an hour, but still ... mwah.

But maybe doing it like that is better than don't have it at all (so, my DAC does 384, but it can't be utilized unless something else than a PC feeds it).

 

Anyway, a creative solution, that USB stick.

Peter

 

 

 

[idiot_savant]

but it's actually got me thinking - the current DAC architectures are, I think, going to start to have problems with these super-high sample rates - for instance, as I've mentioned before, anything using a PCM1704 must have an analogue filter which will cut in before nyquist at 768, so it can't for instance reproduce a 300kHz tone at the same level as a 1kHz one. Whether this actually matters, I'm not sure...

Similarly, a sigma-delta DAC may be able to reproduce it in terms of level, it will be noisier ( due to the noise shaping used ). Again, not sure if it matters, but it would seem that blindly raising sample rates is perhaps a route of diminishing returns...

 

The USB stick thing is clever, but I'm not sure it's that practical, until USB sticks get a lot bigger...

 

your friendly neighbourhood idiot

 

PS what is "arc" upsampling?

 

[ryan_d]

Sorry guys, but this is getting a little silly now. We are talking about music in sample rates that are never going to be readily available for even the most obscure jazz or classical release, let alone anything popular. There may be some releases but within the next 5 years i would presume that the amount of these releases will able to be counted on my hands. We aren't able to get popular music in 24/96 readily at present, so I think this discussion is quite frankly a moot point.

 

All the best

 

Ryan

 

[vortecjr]

will see a usb harddrive...hdd or ssd?

 

Regards

 

Jesus R

www.sonore.us