YULONG's new U18 USB 24/192 Async digital Interface - Page 5

Quote:

Originally Posted by grokit 

The V192 comes with a Windows driver disk.

so, the driver is not required only for linux/mac? That's bad.

I'm curious but what are the advantages of a power supply with converters? I could see the benefit for an amp when one is using harder to drive headphones compared to earphones and can't think of anything really for a converter unless your usb port is splitting power between different things such as if you are using a usb hub powered from the same usb and using multiple outputs at the same time.

I've always wanted a usb to spdif converter but split between this one and the vlink 192 esp since the vlink price seems to have dropped to 199 compared to what it was before. I don't really need one but would be nice to have.

Keeping noise / jitter away from USB is the goal.  Power supplies sometime produce noise and if this noise gets in the USB conversion you'll be getting lots of jitter.  This is the way I understand it.

 

Quote:

Originally Posted by rawrster 

I'm curious but what are the advantages of a power supply with converters? I could see the benefit for an amp when one is using harder to drive headphones compared to earphones and can't think of anything really for a converter unless your usb port is splitting power between different things such as if you are using a usb hub powered from the same usb and using multiple outputs at the same time.

 

I've always wanted a usb to spdif converter but split between this one and the vlink 192 esp since the vlink price seems to have dropped to 199 compared to what it was before. I don't really need one but would be nice to have.

Using an external power supply decouples the USB converter from the noisy power environment of most computers. Linear power supplies are generally quieter than switching power supplies, and definitely quieter and more stable than the power supplied via a USB cable coming from a computer. This, IMHO, is what provides the greatest advantage to using and external, quality, linear power supply to power a USB converter.

As grokit mentioned, battery power is another option. A quality lithium battery is likely to be the queitest/best of all power sources.

The quality of power from a the USB port will vary from computer to computer and as a result so will the degree of benifit from adding the external PSU.  My Alienware M18X is noisier than my ASUS Ultrabook.  In both cases (especially with the M18X) I was able to notice an improvement in sound using a power supply with the U18.

Quote:

Originally Posted by grokit 

It's to isolate the power part of the equation, no possibility of noise from dirty power. But there are other avenues to accomplish this with batteries and circuitry.
If you can get both of them with good return policies would you consider doing a comparison and returning one?

I don't like using return policies that way so no I would not do that. However if I do get the U18 with the power supply I could send it to you but leaning towards the vlink right now but no rush now.

Also thanks for the responses. It makes a bit more sense now.

 

Quote:

Originally Posted by Sonic54 

Mrcasey
I have a question on functionality: is it possible to use two outputs from the U18 simultaneously? For example, AES/EBU to one DAC and SPDIF to a second DAC at the same time? I want to send one signal to my main speakers and another signal to my subs.
Thanks for your help.

I will try that out next time I am at home and have access to another DAC.

I have had great success with the product below for the same implementation in my 2 channel/2 subwoofer set up:

http://www.minidsp.com/products/minidsp-in-a-box/minidsp-2x4

With this you can run dual stereo subs with individual room correction filters on each sub in stereo. You are confined to use the internal DAC in the unit for the analog to digital to analog conversion but this does not concern me too much for the sub 60hz signal that it controls.  The low pass can be set where ever you want with 12, 24 or 48db/oct. slopes.

If you want to run the sub signal through your own external DAC or multiple DACs they have an all digital version as well:

http://www.minidsp.com/products/minidspkits/nanodigi-2x8-k

These are really great units in my experience and have had great reviews from many others.  You will need to use REW and a calibrated mic for room measurement for best results but well worth the effort.

Quote:

Originally Posted by Sonic54 

Mrcasey
I have a question on functionality: is it possible to use two outputs from the U18 simultaneously? For example, AES/EBU to one DAC and SPDIF to a second DAC at the same time? I want to send one signal to my main speakers and another signal to my subs.
Thanks for your help.

I made an inquiry for you about using two outputs at the same time.  I should hear back in a day or two.

Yes you can run the 2 outputs at the same time, someone emailed about it a couple of days ago. While we were waiting for Yulong's answer which is yes, I did some experimenting myself (192/24 into TubeDAC-11, D-100MkII, D-18 and Opera D-8) and found the optical and coax worked fine, so added the AES and the Optical dropped out (digital nonsense noises) Tried a few times powering down everything everytime (which is always recommended) and came to the conclusion that on the mentioned DACs Optical and AES won't work together at the same time. AES and Coax or Coax and Optical work fine together

Couldn't hear any sort of loss from jitter or clocking running both outputs at the same time, but cannot guarantee that different DAC's might not cause some losses, hard to say. I wouldn't run both at the same time for serious audiophile listening as who knows what is happening to the clocking when running other DACs at the same time, some experimentation will be required

Cheers,

Ian