iMac digital output - USB via SPDIF converter or Optical??

[twelvebears]

OK folks, I have searched on here but no-one seems to have given much of a view so I'm asking again.

 

Like many I expect, I'm feeding the digital from my iMac to my DAC (actually direct to a NAD M2 in my case) using an optical cable, but given the talk about the advantages of 'going asynchronous USB' where you let a USB to SPDIF converter do the 'clocking' with (hopefully) a reduction in jitter, I've been wondering if this would be a better option.

 

So there's the question - Do folks think that an asynchronous USB to SPDIF device will be a better option that using an optical output direct?

 

Views, thoughts, or preferably experiences of other Mac users please.

 

[wappinghigh]

I have an Intel imac. Itunes. I'm investigating buying wavelengths's usb-> spdif interface specifically for this purpose. Its bnc/coax at the other end though, so youd need to check the NAD's digital input. My NAD 747 receiver does 24/192. Thats another advantage of these convertors, if you get one with 24/192, you can play these tracks from Linn records and HDtape transfers etc at full resolution straight from itunes (use Max to transcode them to AIFF files...) OSX midi downconverts these when using the toslink optical output.(toslink can only do 24/96)You're also correct about the toslink being jittery.... Cheers.

 

[barrows]

when I was using SPDIF DACs, optical output from a Mac sounded terrible, basically broken. The Wavelink async USB-SPDIF converter was way, way, way better-not a subtle difference at all.

The Mac optical output has been measured to have very high jitter levels, as I recall the jitter from the optical out of a mac would easily be ten times that of a good async USB-SPDIF interface.

 

[wappinghigh]

But get wavelengths brand new interface that does 24/192....its only just out....or one of the other 24/192 interfaces like the m2tech evo, or the Empirical pacecar....but check they are async and the NAD does 24/192 on its digital coax input.....

 

 

[twelvebears]

Fortunately the M2 can take any form of digital input apart from USB, with multiple coax, and digital, plus 75 Ohm BNC (which is probably what I will use).

 

Also it supports up to 24/192 as this is what it already converts it's analogue input to.

 

Right then, a USB-SPDIF converter it is then.

 

Fortunately I've really very little in 24/192, almost everything is 24/88.2 or 24/96, so I'll think about whether to bother with a 24/192 capable device, but as the NAD does it, it seem silly not to really.

 

Thanks again for you replies.

 

[Boy Howdy]

So, if I am understanding the discussion thus far (and as a newly, that is not a foregone conclusion), then the optical TOSLINK out of a Mac is not as good as a usb to S/PDIF connection via something like the MF V-LINK. Am I interpreting this correctly?

 

[Paul R]

(I'm very jealous of that M2, I definitely want one!

 

I have not heard any system so far where even a V-LInk doesn't improve on the optical output from a Mac, if you use the Coaxial output on the V-Link.

 

And there are much better convertors out there, like the aforementioned Wavelength. Note that the V-Link isn't dynamite, and the new model will do 24/192 (available in Decemeber). I

 

-Paul

 

 

[nigel]

In my experience, a USB to SPDIF converter doesn't make any difference with my NAD M2. The sound is equally superb whatever the source. I bought a Musical Fidelity V-Link after reading the good reviews of it here, and I no longer use it. It sounds exactly the same as the Toslink output from a Mac Mini, or (with 16/44.1 sources) from an Airport Express.

 

So, in my experience, the M2 really isn't bothered by any jitter in the source.

 

If you decide to try it for yourself, however, I'd be interested to know if you hear the same thing, particularly as we have almost identical systems.

 

[StudioLou]

Hi Guys -

 

My first post - after reading many from this group! Love my NAD M2 - especially with digital sources. I feed mine mostly 24-bit/88k and above from HDTracks and similar resources.

 

Regarding USB/SPIDF converters versus Mac optical, first: I've been a Mac addict since the beginning, but their optical outs always disappointed - jitter so bad you could actually hear it - not just specs on a page but audible, like some damn robotic mosquito.

 

But now I have a new Mac mini server, sending digital direct via optical to M2. I don't hear any jitter or noise of any kind - just rich, clean, warm music, with tons of depth. Probably part improved Mac architecture, though the NAD M2 white paper describes various techniques to eliminate jitter at output regardless of input, concluding, "Using the j-test to assess data-related jitter, the telltale side bands at 229Hz intervals from the fundamental are totally missing. Quite simply there is no jitter." That may or may not be literally true, but over my B&W 802 Diamonds, it sounds true.

 

As an experiment though, I've decided to add a good USB/SPIDF converter into the chain. After many hours of research, I've ordered an Audiophilleo2, which pushes jitter so low they had to use diagnostic tools designed for satellite calibration just to measure it. Seriously. Here's the company link, followed by a very deep review in 6moons.com:

 

http://www.audiophilleo.com/audiophilleo2.aspx

http://www.6moons.com/audioreviews/audiophilleo/1.html

 

I'll report back after I add the Audiophilleo2 into the chain. No difference would be cool for Apple/NAD, but I'm going for the best sound regardless.

 

All the best,

Lou

 

 

 

[StudioLou]

Guys - I forgot to mention a few key points I learned the hard way:

 

If you want to hear the Mac's optical outputs at their best, be sure to bump up the Mac's core audio settings from default of 24-bit/44K to max of 24-bit/96k. What a difference! On the Mac Mini, "Audio Devices" is in "Audio Midi Setup" in the Utilities folder - you can't miss it.

 

Also, when using the Mac's optical out, the volume control is disabled. When unplugging the optical, the Mac Mini drops output volume to 50%, and it appears to stay that way when you reconnect the optical line unless you manually change it back to 100% first. Supposedly the Mac only outputs full resolution at full volume, because the volume reduction algorithm actually dithers down bits of information; not sure of the math/logic here but I've noticed a definite qualitative difference at lower volumes.

 

Finally, I treat my Mac Mini like a serious audio device and filter power going into it via the same device filtering my NAD M2 and SACD drive, namely my Tributaries T200 power manager. Hard to tell sometimes what's doing what in a system, but all these technologies and processes together are finally giving me the sound I've always wanted - at a fraction of what I thought it would cost. We'll see if Audiophilleo2 can add anything to this (aside from obvious 24-bit/192k output).

 

-Lou

 

 

[Moondreamer]

Perhaps i just don't get it, but how is it possible for me to adjust the optical out volume? My speakers are directly connected to my Mac Mini. I am affraid that my settings are incorrect. Can someone guide me?

 

Greetings Brian

Mac Mini, B&o Beosound 5

 

[LikesToys]

Hi Guys -

 

My first post - after reading many from this group! Love my NAD M2 - especially with digital sources. I feed mine mostly 24-bit/88k and above from HDTracks and similar resources.

 

Regarding USB/SPIDF converters versus Mac optical, first: I've been a Mac addict since the beginning, but their optical outs always disappointed - jitter so bad you could actually hear it - not just specs on a page but audible, like some damn robotic mosquito.

 

But now I have a new Mac mini server, sending digital direct via optical to M2. I don't hear any jitter or noise of any kind - just rich, clean, warm music, with tons of depth. Probably part improved Mac architecture, though the NAD M2 white paper describes various techniques to eliminate jitter at output regardless of input, concluding, "Using the j-test to assess data-related jitter, the telltale side bands at 229Hz intervals from the fundamental are totally missing. Quite simply there is no jitter." That may or may not be literally true, but over my B&W 802 Diamonds, it sounds true.

 

As an experiment though, I've decided to add a good USB/SPIDF converter into the chain. After many hours of research, I've ordered an Audiophilleo2, which pushes jitter so low they had to use diagnostic tools designed for satellite calibration just to measure it. Seriously. Here's the company link, followed by a very deep review in 6moons.com:

 

Audiophilleo2 - low jitter USB SPDIF transport,converter

6moons audio reviews: Audiophilleo 1 & 2

 

I'll report back after I add the Audiophilleo2 into the chain. No difference would be cool for Apple/NAD, but I'm going for the best sound regardless.

 

All the best,

Lou

 

 

I realize this this is all the way back to 2011 but I am considering a used m2 so would like to know if I can just go from toslink on mac without problems

 

also do you still like the m2?