I think it depends on the output. I've never seen a PCI or USB device that used digital attenuation (although maybe one exists somewhere). For HDMI, I think they're usually digital based just because HDMI doesn't (AFAIK, correct me if I'm wrong) support volume control since its intended that the HDMI receiving device will implement volume control.
For USB, it'll be analog. I don't know about Toslink. Its older then even Windows, it may not support volume control commands. When you set volume to zero, typically that enables the device's mute register, which puts the output amp into powersave mode.
What struck me is that very few manufacturers of DACs with a USB input claims the volume control over the USB is done analog. As digital volume control has a bad reputation in the audiophile world, I expect them to claim analog volume control when they have implemented it.
I wouldn't be surprised if they have no idea how volume control is implemented.
Comments and suggestions greatly appreciated.
Quote from: FiddleMinger on 06 April, 2013, 02:58:09 PMComments and suggestions greatly appreciated.Get an AVR. You can get one for less than $200. They have just about every kind of digital input. They have good DACs, analog volume controls and bass management, and built-in power amps. Most also have built-in multi-band equalizers. You simply configure them for as many channels as you want to use.http://www.accessories4less.com/make-a-sto...Receiver/1.html
As for the 30' remote signal source, I assume you mean your PC is remote from the amp. Lots of systems available to do Wifi streaming. If the signal source is in another room you will also want some way to control it remotely.