[Blackwheel]

I was wondering if anybody knows how these two compare?

vs.

 

[Yoga Flame]

I only own the Transit. But here is a comparison based on what I have read.

M-Audio Transit
+ Max 24 bit / 96kHz (both in and out)
+ Analog line-in input
+ Optical input
+ Inputs can be recorded to computer
+ Optical output
* Digital volume control from computer
* Powered by USB
- Requires drivers (available for Mac OS X and Windows)

Nuforce uDAC
+ S/PDIF coaxial output
+ Analog RCA outputs
+ No drivers required (?)
* Analog volume control on the uDAC
* Powered by USB
- 16 bit / 48 kHz


The Transit's recording capability probably isn't relevant to most readers here. But it may come in handy if you ever need to record something in the field. The 24 bit / 96kHz is nice, but bear in mind that normal CD quality is just 16 bit / 44 kHz.

Drivers for the Transit have been known to be a little flakey on the Mac. There's a workaround: Replace the M-Audio Transit USB soundcard's drivers - Mac OS X Hints
But note that it was posted in 2004, and M-Audio have updated their drivers since then. I'd still prefer if drivers were not needed at all though.

Digital vs analog volume control is a subjective preference. Digital means there's no volume dial on the device, so you must do it through the computer settings. You can also control the volume from some computer keyboards. Analog gives you finer control, and a convenient dial, but system volume settings on the computer will have no effect. Application volume settings (e.g. iTunes) should still work, but I suggest leaving that at 100% all the time for best sound quality. Otherwise the signal gets messed with twice--once by iTunes, and a second time by the Transit/uDAC.

Can't compare the uDAC sound quality since I have not heard it. And that is really the main question here, I think. Looking forward to hearing from anyone who has both.

 

[gbacic]

Digital volume control and analog volume control is not subjective.
Digital volume controls usually worsen the sound quality by throwing away bits to lower the volume, while analog does not. Snow Leopard iTunes apparently has a 24 bit, dithered volume control (which is very good, supposedly) but I'd still rather have an analog volume control rather than digital.

 

[joe_cool]

I've read reviews comparing the Transit to more costly devices and it performed well, low jitter with asynchronous USB.

 

[Yoga Flame]

Quote:

Originally Posted by gbacic /img/forum/go_quote.gif Digital volume control and analog volume control is not subjective. Digital volume controls usually worsen the sound quality by throwing away bits to lower the volume, while analog does not. Snow Leopard iTunes apparently has a 24 bit, dithered volume control (which is very good, supposedly) but I'd still rather have an analog volume control rather than digital.

I certainly agree that lowering the volume in iTunes (or any other application) will worsen sound quality. iTunes volume should always be kept at 100%.

However, there is the matter of the system volume, which is different from the application volume. In Mac OS X, the system volume is the one that you set from the desktop menu bar, with a vertical slider. It affects all applications, and not just iTunes. The application volume is set by the horizontal slider inside the iTunes window.

As I understand it (and I may be wrong here), when setting the system volume for the Transit, OS X does not change the digital signal that it sends over the USB cable. It merely tells the Transit, "lower the volume to X". And the Transit then factors that in during the digital to analog conversion. Now of course it's possible that the Transit also ends up throwing away bits to lower the volume. Or maybe it regulates the op-amps to produce lower output? But that's beyond my knowledge.

 

[joe_cool]

I agree with what you said but I doubt the Transit has the ability to modify the analog volume.

 

[techenvy]

should be an interesting compare may want to add the teralink in there

 

[nycdoi]

you can just max out the volume on Transit and use another amp for volume control cant you?

 

[joe_cool]

Unsubscribe...

 

[Yoga Flame]

Quote:

Originally Posted by nycdoi /img/forum/go_quote.gif you can just max out the volume on Transit and use another amp for volume control cant you?

I think maxing out the volume for sound quality only applies to line-out or digital signals. The Transit has a headphone amp built into it. So re-amping its output at full volume could result in some distortion.
Edit: I stand corrected. Since writing the above, I have obtained a proper headphone amp (Aune), and connected the Transit's analog output to the Aune's analog RCA inputs. Even when the Transit is at full volume, I can hear no distortion. Interestingly, using the Transit as a DAC for the Aune in this way produces a cleaner sound than using the Aune's built in USB DAC, superior to using either device on its own. However, if I had to choose just one, the standalone Aune sounds better than standalone Transit. And if you replace the Aune's stock opamp chips, the improvement is even greater.
 

For what its worth, when I listen to my Transit directly at the lowest volume, it sounds fine. In fact, I would say the sound quality of the Transit at low volume is better than the built-in headphone jacks from either my iPod or my Mac at higher volumes. (With ATH-M50 headphones.)

The problem for me sometimes is that the lowest volume out of the Transit is not low enough. If say, I don't really want to focus on the music and just want something going on in the background, for example. But I suppose the quality loss by lowering the volume in iTunes won't matter for that.

It'd be interesting to find out what stage inside the Transit does the volume get lowered. If there's a volume potentiometer in it, it would have to be the solid state kind. Or does it simply amplify the signal less (does that even make sense)? Sorry, I am not in any way an engineer.
USB -> DAC -> Amp ->Pot(?) -> Out

Anyone know? And how would that compare with the analog volume pot on the uDac? (See, we're still on topic, haha.)