[mozartino]

why not?

 

[Shaman]

Well I had actually hoped to get some measurements and compare the noise floor between my PC card the external DAC I picked up.

Unfortunately my techtronics mainframe is having some issues so I can't do anything formal. I did subjectively compare the two. I hear no difference in the reproduction of sound between the BiFrost and my old PC DAC on my headphones or on speakers. Musically they are both transparent as they should be.

Then I tried foobar with a highly attenuated output and then cranked my headphone amp way up. I think a very weak signal is better than a null signal because it gets the output circuitry working on the DAC and that is where the noise will come from. I could notice the difference in the noise floor, and yes the external unit was slightly better. I moved to one of my DIY amps and some monitors, again at high gain the noise was clearly less on the external unit. This amp is an exceptionally clean highly biased AB MOSFET design. Any audible noise over the very faint music playing at high gain would be from the source. I then hooked up an old Yamaha p-series amplifier I had been working on and did the same thing. Full tilt gain with that kind of horsepower ( its a 50lb power amp) is a bit unsettling, but the amp produced more noise than the either DAC, although that amp is quite clean for a pro amp of that age.

So yeah there is a slight drop in noise, and there was no particular frequency, just a faint static hiss, no 60 hz hum or anything. If I had some ultra high end speakers that were sensitive enough then the external DAC would be a must, but otherwise it is doing the same job my old set-up did. I do like the ability to just grab the unit and use it elsewhere, the bifrost has no power brick, and who doesn't already have to many damn power bricks.

I took the metal surround off the Bifrost it is the version using the AKM 4399 if anyone was curious since it seems they have about 6 different versions of that unit.

I usually don't pay much attention the the DAC side of things, I build amps and play around with speakers mostly. But this has been fun to mess with.


edit: I did not mess around with my PC much though, there are some causes of noise that could be an issue, like a HDD spinning up. I just had Foobar running, I did try both AISO and WASAPI for kicks. AISO tends to be better on this computer setup.

 

[iFi audio]

why not?

Not sure if this question was related to our previous post, but here goes: a separate DAC is just another device one can pick to fit in his/hers setup specifically and net a desirable sound profile or/and functionality.