[ebag4]

Guys,
I currently run a SB3 but am playing with USB DACs.  I have been using an old 1G AMD machine as a music server.  This unit is old enough that it did not have 2.0 USB ports, only 1.1.  I added a 2.0 USB PCI card, ASIO4All (W2K Machine), Foobar 2000 with Asio Plugin.  The sound was not good, very boomy.  I then set up my HP XP laptop with FB2K and Asio4all, much better.  My issue is that I still hear some very low level noise coming out of the drivers when no music is playing.  I don't have anything else plugged into the USB ports, however, the internal optical drive is on USB internally.  I have tried all of the ports with no change.  With the USB cable unplugged from the DAC no noise is generated, the cable is 6' long.  BTW, Windows sounds have been turned off in both instances.

Unless someone can recommend a way to fix this setup I have decided to by a new motherboard, processor, and RAMM.  I am looking for an inexpensive rebuild of this PC, the solution needs to be able to support my old ATA drives.  Integrated video and network would be a plus although I will typically running the system from my PDA with the PC in another part of the house.

Any recommendations?

Best,
Ed

[Scott F.]

Ed,

One thing I've heard several people say is that MACs sound better than a PC. I haven't tried that one yet but if I do, those same people have suggested a MAC Mini ($600-$800 refurb with warranty). I believe there is a FLAC plug in for iTunes front end. There may also be other music server front ends for the MAC if you don't want to use iTunes.

....just a thought

[Folsom]

PC's have what is called the "K-kernal" which drops bits, inherently, in windows, regardless of everything. Foobar2000 does as much as it can to work against this, but an Apple still have the advantage that it does not suffer from any drop.

The real truth is that more likely than anythin,g the unfortunate truth is that you are experiencing an issue that is associated with SPDIF via USB (noise, I2S is a possible way around this, more complicated setup if possible). You could use an airport and Pacecar digital re-clocker to get digital to a DAC instead of USB, and probably have pretty clean sound, at a huge premium.....

That is what I have experienced, and read about the most, USB and SPDIF is just not jitter and noise free at all.

[WGH]

Ed,

Try the USB-Audio driver as a test for noise.
http://www.usb-audio.com/download.html

Once installed and Foobar is reconfigured



do you still have the noise?

Wayne

[NewBuyer]

Hi Ed,

Does it absolutely *have* to be a USB-only DAC?  Just wondering if you've tried/considered the other interface options.  Also, have you considered continuing to use your SB3 along with a pda-control plugin?  Or perhaps using the Logitech Controller instead of a pda?

(Seems like you might have lots of options here besides doing a computer rebuild just for usb...)

[EchiDna]

www.silentpcreview.com

damn good recommendations on all quiet componentry...


I recently bought an Enermax Modu82+ 625W power supply as recommended on that site - I cannot audibly tell the PC is powered up apart from visual indicators (LED on the case), even from half a meter away. it helps that my motherboard controls the fan speed, but its amazingly quiet (under a measured 20db in use).

[MerlinWerks]

PC's have what is called the "K-kernal" which drops bits, inherently, in windows, regardless of everything. Foobar2000 does as much as it can to work against this, but an Apple still have the advantage that it does not suffer from any drop.

Are you saying "bit-perfect" playback is not possible? I think there would be many who disagree. The K-mixer in Windows is responsible for mixing all audio streams and will resample to a common rate if the various streams are at different sample rates. However, in XP 32 it is possible to have bit perfect playback even without any special drivers (ASIO, KS) as long as certain criteria are met:

Only one application is playing, which also means Windows System Sounds are off.

Wave volume is at 100%

The player was compiled as a 32 bit player

Applications that both playback and record have to have the same sample rate set for each function

Your sound device doesn't resample in hardware

More info HERE

[woodsyi]

Is bit perfect jitter free?  Even if you get your ducks in a row, will they keep strait line and march on time?  Is this possible with noisy SMPS?

[ebag4]

Thanks for the feedback guys, a little new info.  I have found that if I unplug the laptop from its power supply and let it run on batteries then the noise through th speakers is completely eliminated.

To answer a couple of your questions:

*I have considered buying a Mac Mini
* I am aware of the Kernel issue within Windows, in fact I am successfully running Kernel Streaming on my HTPC and have been for years.  BTW, it is my understanding that other than mangling the signal the issue with the Window Kernel is that it upsamples everything to 48.
*I tried the USB Driver, thanks...issue remained
*Yes, I have the USB Dac in house so that is what I would like to use plus I like the simplicity of the system
* In light of the recent finding that the laptop power supply is causing the noise, a power supply may be the cure I am looking for but it will only come with the rebuilding of my server machine

If you have any other recommendations please feel free to list them, it is appreciated.

Best,
Ed

**Update**
A cheater plug on the laptop powersupply completely eliminated the noise, dead silence when no music is playing.
Thanks guys!

[MerlinWerks]

Is bit perfect jitter free?  Even if you get your ducks in a row, will they keep strait line and march on time?  Is this possible with noisy SMPS?

Of course bit perfect and jitter are two separate issues that need to be dealt with separately and where the degree of audibility of either is certainly up for debate. Since it came up, I just wanted to provide a link to what I feel is some solid info on part of the PC audio chain that is generally misunderstood and as a result lots of erroneous info gets posted.

[EchiDna]

www.silentpcreview.com

damn good recommendations on all quiet componentry...


I recently bought an Enermax Modu82+ 625W power supply as recommended on that site - I cannot audibly tell the PC is powered up apart from visual indicators (LED on the case), even from half a meter away. it helps that my motherboard controls the fan speed, but its amazingly quiet (under a measured 20db in use).

*sigh*  read the question properly EchiDna before answering!

*sigh*