iTunes bitperfect in windows

The Sonos output seems to be pretty good. I was lucky enough to be able to compare one with the digital output of an HDX a while back through Cyrus and Lavry DACS. There was more of a difference between different SPDIF cables we tried than between the two sources. I think the 552/500 system being used wasn't revealing enough to differentiate the sources...

I reckon that if the Naim DAC cuts it soundwise (which i have no doubt that it will) then the combo of a Sonos with Naim DAC will be a very good (and convenient) way of listening to music with the bonus of the other zone playback too.

James

Love the Sonos and prefer it to a SB etc(haven't tried a transporter) but find a clear difference between it and an HDX or TC/ASIO for instance with the DACs I prefer. I like the HDX with nothing plugged into the burndy socket when used as transport and grounding needs to be rechecked depending on confiduration. Of course cable differences can also be more than subtle. These differences would also point to bits as not just bits and subject to imperfections in transfer. Not in data(still perfect) but in timing, noise and hinges.

One issue with Sonos is the lack of Hi-Res capability and it could be a bit quiter but it is generally musical and a great solution for it's intended market. I've sold and setup plenty. Well engineered and consumer freindly device.

For anyone who is interested in his views ... I was reading today that Kent Poon has discovered that if you set the correct bitrate in the Quicktime control panel (and with Vista in it's own control panel) iTunes IS bit perfect under windows (assuming 100% volume, etc). This was contrary to his original findings. I know other people disagree with his findings but he was thorough in his original testing.

Eloise

Eloise,

Ive heard the same stipulation on player volume for iTunes.

It was once thought that Foobar's volume suffered the same resampling but it was found not to be the case. Although I keep Foobar volume at 100% just in case.

-Patrick

I think you are right to leave the Foobar volume control at 100 - I don't think it could give you bit perfect playback under any other circumstances.

Likes,

I believe it is actually just fine to use Foobar's volume.

System volume should be @ 100% if NOT using ASIO. Maybe that's what you are thinking of.

Even in the latter case, WITHOUT ASIO, you can still be bit-perfect as long as there is only one stream of audio playing.

In the end though, if everything is kept at 100%, there should be a guarantee of transparency.

It's been a while since I played with foobar and ASIO. Is it not the case that the Foobar volume control affects the volume with ASIO? If that is the case, then there can only be one setting for which it is bit-perfect.

likes,

I am not sure.... All I do know if that Kmixer is theoretically capable of over 192 kHz, though we have only proven its capabilities up to 96 kHz. With sample rates up to 96 kHz, we have tested and proven that Kmixer is bit-transparent under normal operating conditions. That is, it will not affect the audio whatsoever, as long as the volume is set to 100% and only one application is playing audio.

This why I have never used ASIO until recently I was requested to give it another shot by a forum member.

I still cannot tell if there is a difference between ASIO and DS.

I will most likely go back to DS for a while and see if I can tell a differnce going the other way.

quote:

Originally posted by likesmusic:
It's been a while since I played with foobar and ASIO. Is it not the case that the Foobar volume control affects the volume with ASIO? If that is the case, then there can only be one setting for which it is bit-perfect.

Surely the use of ANY digital volume control looses bit perfection as a digital volume reduces the numer of bits used for the signal. What doesn't have to happen (but may with some software) is that the signal goes through sample rate conversion when the volume is used.

That's not to say that a digital volume control (used carefully) isn't an acceptable solution as a good digital volume can be (audibly) transparent.

Eloise

The only way to get a reasonable result and not lose significant bits is to increase the bit rate, adjust and convert back. This isn't happening with in foobar in ASIO. I did hear a difference with ASIO in foobar with XP with windows sounds etc turned off. It may not be bits but noise etc but for me, it's there. Can't comment on what differences may or may not exist in Vista but the V control should be better as I believe that it does use 32 bit float in volume conversion. I do suspect that MS have offered wasapi for a reason. It would have been more PC for them to just say no benefit.

This is interesting http://www.hydrogenaudio.org/f...=109854&#entry109854 If you look at the #s, there's a change but the amount would seem inaudible so there's always room for debate. I just go by my observations as we all should but we should also be using top kit when speaking in absolutes. Not hearing a difference in other configurations is like trying to prove a negative, valid as it may be for a particular setup. It's why I never question when some one hears a difference but can't be sure when they don't.

quote:

Originally posted by Eloise:

quote:

Originally posted by likesmusic:
It's been a while since I played with foobar and ASIO. Is it not the case that the Foobar volume control affects the volume with ASIO? If that is the case, then there can only be one setting for which it is bit-perfect.

Surely the use of ANY digital volume control looses bit perfection as a digital volume reduces the numer of bits used for the signal. What doesn't have to happen (but may with some software) is that the signal goes through sample rate conversion when the volume is used.

That's not to say that a digital volume control (used carefully) isn't an acceptable solution as a good digital volume can be (audibly) transparent.

Eloise

That's precisely what I was trying to suggest! A digital volume control must, by definition, alter the bits at every setting bar one, just as an analogue volume control alters the amplitude at every setting bare one, otherwise it wouldn't be working!

I believe there are arguments that a digital volume control, if you have enough precision, can be very good. There is a very fancy processor in the new DAC.. if they used it to implement a digital volume control, the DAC would become a digital pre-amp - all you would need if you don't have any analogue sources.