NDX and Chord Hugo

Thanks Simon. I will probably put the Hugo on the low spare shelf. It's not possible to put it on the top level as the PS DAC is too big to go anywhere else.

I suspect that won't make a huge difference.. As with the others am interested to hear how you get on.

Enjoy...

Simon

Steve

if you get a chance would you compare wav and flac files into these two as well.

Graeme

Will do. 

Wat, what are you trying to say here...?

"we are probably talking 0.0003% at 0db in sound quality terms"

Thanks Wat for your prompt advice earlier today. Will give it a go in the near future with my US/SU combo. Must admit I love the simplicity of Nstream but if sound is better may be prepared to faff around with the N-serve app as well.

Wat - I believe that Rob Watts advocates optical where possible, and he has also said that the Olimex USB isolator improves performance of the SD USB input on the Hugo. 

Yeah I didn't understand that either.  Was he not talking about a digital signal going to a DAC?  So what is the distortion of the digital signal and why on earth is it important - IT IS DIGITAL?  I ain't even gonna ask what is 0db in the digital World.

You wouldn't want your 'transport' (whatever that transport is?) to send a lot of noise to your DAC, I don't think anybody would disagree with that.  But obviously some DACS would have better noise rejection than others.  The Hugo noise figure quoted of -136db I would expect is any noise generated by Hugo itself, after all its designer could have no idea what noise is going to be sent to it.

The idea of using a PC (of any make, yes Apple too guys) as front end to a DAC seems like dangerous talk to me but if the Hugo is good enough at noise rejection and it is an asynchronous (ie re-clocks) DAC then even though it is expensive it will make a fairly cheap system.  Just strap-on a 24-bit capable sound card (cheap), isolate the PC mains and you are away.

Is this a viable option?

Many Thanks Steve

To be honest Wat I never said that at all.  But if the same PCM is being sent to the DAC with the same noise level then it MUST sound the same.  Maybe in your example the noise level is different.

No my question was what is the distortion in the digital stream?  In theory every digital stream has a level of distortion with respect to a sequence of perfect square waves.  A perfect square wave is something that cannot exist in actual circuits, only on the design board.  But it doesn't matter, a figure of x% distortion in a train of pules will NOT equate to x% when we get to the analog domain.

I also, like Simon, could not understand what 0db is in a digital stream for much the same reasons as above.

A good sound card would not make things sound worse but it probably would have more positive impact if you were using its analog out and not feeding a DAC with digital.

I thought that the Mac mini only worked to a max word length of 16bits and I guess most Windows PCs have this limit with the basic sound cards they come with.  Or is this 16bit limit just an iTunes limit - just don't know tbh.

The Mac (and iTunes) support 24 bit with no issues. 

erm chord Hugo a game changer?

to deserve that - it needs to compete favourable with an LP12

That's the day any digital source has the right to call itself a game changer

till then, it's just another digital source that allegedly sounds less harsh, also subjectively.

Anyway there is a lot more to the "less harshness" game for a digital source to compete with analog tape or analog sourced vinyl.

There is accuracy of the timbre, natural decay of notes, air and space, and sheer emotion and musicality.  Many things that can't be measured, but you know the real thing when you hear it.

to all the fans of the latest flavour of the month. Ignorance may be bliss, but it sometimes isn't the truth.

I don't get the fascination with LP12 comparisons. If that's your reference then you're going to be on a very long road to finding digital Nirvana.

Vinyl may be very good, but doesn't appeal to all. 

Ah!  I have answered my own question.  The hardware in a Mac Mini can do it but you need the software to do it.

ps looking at the specs on my Gigabyte motherboard it would seem that this can do HD too!  Well I never, I never trusted a PC for Audio but it looks like a might be wrong.

Have a read of an article about iTunes and HD: Read This

He says in this article that Apple won't do HD Audio for at least 3 years because ISPs won't like shifting a whole load of data out. But don't movies use a lot of bandwidth?  I suppose with music people may be listening for longer periods though.  An interesting article to read.

Sorry Wat but now you really are confusing me old chap.  I thought you were saying that if your playback software converts FLAC to WAV at runtime then that sounds different to when it plays WAV at runtime???  Were you not saying that then?

No I have tried WAV and FLAC (converted from the WAV) and could detect no difference.  I have also tried using WAV and FLAC transcoded to WAV and heard no difference. 

FLAC is bit perfect and if you don't believe me then go to https://xiph.org/flac and look at their test suites, I think you can even download and run them yourself.

BB

I use an iFi supply between iMac and Chord DAC, and my ears also agree Mr Wat.

clarification

"

Hugo takes no power over its USB input (as this is severely limited with many partnering products) and only takes signal data, therefore, it is fully compatible with all iPhone, iPad and Android devices.."

"

...Hugo also benefits from two advanced USB inputs: one for legacy USB devices, plus a high-definition USB port for operation up to 384kHz ..."

Hi Wat -

I would hazard a guess that you prefer how the DSD version of the album was mastered.

This might be an interesting test: take any DSD file, and use Korg's Audiogate (free download) to create a FLAC version of that file.

Try to keep the sampling rate close -- say DSD64 versus a 24/88.2 or similar FLAC file, and then play both through the Hugo.  I am pretty sure that Hugo uses one, common output stage, so volume levels should match.  This should eliminate any differences in mastering, and the difference in sound quality, in theory, should come down to the decimation errors caused by the DSD-to-PCM conversion process.  More specifically, it will come down to a comparison of the two conversion processes: Audiogate's and Hugo's internal conversion of DSD to PCM.

If you can not hear a difference, then it is the mastering. If you do still hear a difference, I would be curious if that is Hugo-specific, or if you also hear a similar difference on your Teac dac.

But before you go to any trouble, I'd invite Aleg, S-i-S and others to comment on whether or not this would be a valid and/or useful experiment.

ATB.

Hook

It looks like in this case you'd be better off with a breaking the 5v line at the source.

Does the IFI just provide a regulated 5v or does it break the ground path from the source computer too ?

no trouble Wat - the 5V would be redundant but does iFI offer better signal shielding than the standard cable? - I do not know.

Hook

When converting DSD to PCM there is always the question of what to do with the high frequency noise in DSD, what type of dithering to apply and whether to apply the 6dB volume correction because of the lower sound level of DSD.

Korg will offer you no noise filtering or soft rolloff or steep filtering.

For dithering I think most advanced algorithm from is Aqua dithering.

And I would apply 6dB volume correction as this is standard difference between DSD levels and PCM levels.

but the comparison will contain the noise filtering and dithering, so it can't be a straight one-on-one comparison with just a DSD to PCM 'resampling'.

one could turn of all filtering and dithering but I don't think you'll get an honest conversion.

cheers

aleg

Interesting, Aleg; thanks for that!

Me too but with Apple!

btw what is JRMC?

Thanks Aleg. I don't think the internal filtering in the Hugo can be turned off. Watts definitely says that he strips out the high frequency DSD noise, but I do not recall him saying how he does it. I don't recall reading if the Hugo applies extra gain to DSD input, but I would guess it does.  Otherwise, I would think DSD files would sound noticeably quieter.

Oh well, it was worth a shot. In the end, it is merely an intellectual exercise. So long as Wat and others are enjoying DSD files played through the Hugo, that's all that really matters!

ATB.

Hook