transcoding flac on the fly to Wav

You do realise you are opening a can of worms here I trust.

OK, Naim say their streamers are optimised for WAV, many of us say we prefer the sound WAV files produce. However, just as many others will say they can’t hear any difference. It’s one of those suck it and see (hear) propositions.

Peter

I use ALAC and iTunes sends this as PCM to the Naim DAC which is the raw native format for the music ... no WAV required here ... all lossless formats go the DAC as exactly the same noiseless, low jitter stream. I can even send DSD streams as PCM from the Mac Mini to Naim DAC ... I'm delighted with the way this works and will bot be going back to UPnP 

As Peter says Naim streams are optimised for WAV .... so I avoid them they are just too complex for me. Sound good if you can figure them out though. 

Hi.. Yes as intimated this can arose emotions... So either stream or play FLAC or PCM files into the DAC / network player and see what sounds best to you.. If the same then chose FLAC as the files are smaller. 

As far as PCM, there are two file types commonly used in our gear.. WAV files or AIFF files. They are essentially the same other than the sample bits are reversed. Of course when sent as SPDIF or Isochronous USB the PCM has to be  chopped up somewhat and then reconstructed but that's another story.

Simon

I can hear a difference between flac and wav if both are sent to my SU. If the flac is transcoded to wav by the player/renderer it sounds just as good as wav. I do that because flac is better for tagging and uses less storage.

There should be no difference between flac and wav as both are lossless but some people can hear it (though to me it is very slight). The most plausible theory  to me is that doing the conversion/decompression processing in the streamer causes some kind of degradation. Hard to explain why but there are a lot of things that shouldn't affect sound but clearly do. Mains leads anybody? (note - that last question was strictly rhetorical!).

It goes without saying that you should use a powerline on the pc you rip your cds with.

I don't .. should I re-rip all my CDs with a Power-Line connected to my Mac just in case?

Can I still use XLD or must I use Jack the Magic Ripper? I don't trust that Accurate Rip database, I mean just 'cos it says my rips are fine what does mean. I might have the same wrong rips as everybody else who didn't use a Power-Line. So must I re-rip? 

If you say yes then I'll book a couple of weeks off and go back in to the lead lined bunker in the garden to redo everything. 

Sometimes I think I'm Napoleon does that matter .... 

OK call me a loony, but if I send PCM from my Mac to UQ and send the data back then I get the same whether it is ALAC or AIFF ... does this not mean that if goes to a buffer in a Naim DAC then it is the same PCM. If the different formats sound different then something deep inside, which cannot be denied, keeps telling me that they what is being played by the DAC would be different ... but every thing I try leads to the conclusion that the data are the same. Why does it matter what container they were in when the Mac has ousted them from their containers. 

The only advice I can give is use which ever one you like and believe sounds best - I fully accept that if the whole job was going on in the Naim box then it might have an effect, but I cannot see why if an external box is doing the rendering this is different from a NAS doing transcoding. In both cases what the Naim system gets to act on is the same. 

I also accept you can hear differences if you play the same track twice, but perhaps this is because something else has changed ... the temperature of the room or anything really? 

With no offence intended, personally I think the most plausible theory is that people are imagining differences.

(Funny how one always prefaces offensive comments with "no offence" isn't it?)

'Fraid so.

And of course the Power-Line must be connected to an unswitched medical grade socket wired directly back to it's own fusebox with a single run of 10mm cable.

And even then it's better to rip at night. 

And a Power-Line on your NAS, obviously.

You guys are nuts

I have an arrangement with my local electric company.  They run a plutonium wire straight from the voltage generator to my house.  All other solutions inject jitter and evil humors.  This only costs me 2 million dollar a month, which I could use to upgrade my speaker cables but.....

What?  No flux capacitor?

A bit off topic, but does adding a Power-Line to a CD or vinyl record cleaning machine make as much difference as everybody says? 

Oh yes Guy. The vacuum pump seems to work more smoothly and effortlessly with the Powerline on my RCM. Seriously. 

Greg, you should be posting on the car nostalgia head with photos like this

WTF?

It gets more confusing. Depending on the nas or airport or what ever those packets might be compressed back up into something for the journey.

My opinion is concentrate on making your library work for you with artwork location etc and purchase a decent router and switch.

If you are using a homehub or superdud hang your head in shame.

Paul, you really must keep up with other threads.

Cheers

Don

I can hear differences between WAV and FLAC in my system. Don't know or care what the causes are, but definitely not my imagination. Mind you the differences are not night and day, also quite track dependent.

I am not offended by your opinion which I respect. I think others will feel the same. If you cannot hear any difference that's fine by me. However your view might change if you have the chance to hear the systems of those that can. Senses and perception including hearing, eye sight, etc. can vary considerably from person to person. 

Yep there are differenes between FALC and WAV decoding and EMI casued. This is not voodoo, but a rather established field that is used in certain reverse engineering facilites - such as reverse enginerring smart cards - must keep in general here but I have visited certain government sponsored facilites (non UK) perform this and it  is fascinating. I find it bizarre that one can think that their humble Naim network streamer boards are somehow immune from this...

Anyway the phyics and engineering aside, if you can't hear a difference then great.. if you can - you know what you can do about it - no big deal.

Simon

Interesting thoughts.  I don't know whether it does exist but happy to be shown.  Either way, it's easy enough to transcode or create versions of multiple files with many of the rippers/transcoders so it's not much work if it needs to be done.

Assuming it's a real effect we should be able to measure the output of the same track on WAV vs. FLAC, diff the waveforms and see if they vary enough for it to be discernible?  This will put the entire theory to bed one way or the other....someone somewhere must have done this already as it can't just be a phenomena specific to Naim gear?

Yours open mindedly,

scm77

PS: Apologies if this has been covered previously....

SCM77 - if you look at the waveforms, can i recommend its best to look at the output from a sensitive spectrum analyzer - you might well see some *very* low level HF differences. REmember this has nothing to do with the sample data and ripping etc

Do you know of anyone that has done this analysis?  I certainly don't have the equipment, expertise or knowledge to execute it myself but would love to know a definitive answer.

On one hand I'll need more disk space and a bit of time to transcode but on the other it is essential a free upgrade if it exists as I am all FLAC at the moment....

I assume you are suggesting the HF interference comes from the processing components being slightly more stressed by decoding the FLAC - which makes sense from a computing perspective although I have no idea on how much this translates to interference - way outside my comfort zone there!

Best

scm77

Hi, I haven't done on it on Naim kit, but I have seen the effect elsewhere.. Subtle changes in sound and other signals are sometimes best observed at looking at discrete frequency components rather than the shape of waveforms... As we know all wave forms can be broken  down into summation of sinusoidal frequencies.. Interference from RFI can manifest as unusual spectra appearing. These frequency components when added to the spectra of the  wanted signal can subtley change the wanted signal shape - ie distortion. This RFI can be derived from EMI from high speed logic switching circuits and their modulation of the earth and power lines/PCB tracks. You usually mitigate by using shielded multi plane PCBs and tiny capacitors across the Powerlines very close to the switching circuits... But alas these endeavours are not usually (can they ever be?)  perfect, as there typically is recognizable modulation above the noise floor.

Have you got any such data about naim players? Could you post it? Have you ever seen any? Do you have a reference to it? Or are you just speculating?

Thanks for the info Simon - I feel some googling coming on  

I think there are two different set of changes that I have heard before.  The component upgrades that have an immediate and obvious effect and then the less tangible ones that over a period of days or weeks you can't put your finger on but make you want to listen more (or less).  This clearly fits into the latter category I think.  Having listened to a few portable DAC/amps as well I can certainly appreciate that there are subtle differences that have a long term almost subliminal effect.

Either way, happy listening and enjoy the weekend snow!

Best,

scm77