USB Amplifier

A lot of audio equipment has a digital input (optical or coax), very few computers have a digital out . Apple and of course Toshiba are the ones I know having a headphone out doubling as a (mini) Toslink out.
Every PC has USB but very few audio equipment has a USB input.
Except of course for the USB speakers but these are targeted at the desktop.
Slowly but surely DACs appear on the market with a USB input.

Amplifiers supporting it all, USB, SPDIF and the normal analogue inputs are rare.

A list of amp's with digital inputs can be found here: HTForum

April music Stello Ai500 Integrated Amplifier $3495 USD

Output Power	150 Watts/CH @ 8 Ohms, 300 Watts/CH @ 4 Ohms
Output Stage	Quad Para Push-Pull Hitachi MOSFET Power Transistors, Class AB
Power Supply	Custom Made 800 VA Toroidal Transformer 90,000 uF Capacitor Bank
Frequency response	20~45 kHz
THD + N	< 0.05 %
Volume control	Cirrus logic CS3310 digital volume control
Analog inputs	3 unbalanced analog line inputs 1 balanced analog line input 1 BYPASS input
2 Analog Outputs	Pre-out, REC
4 Digital inputs	COAX, OPTIC, PC USB Link, iPod COAX : up to 192 kHz / 24 bit PC USB, OPTIC : up to 96 kHz / 24 bit
Front Panel	POWER, BALANCED, CD, TUNER, AUX, DIGITAL, BYPASS, MUTE, Rotary Volume Encoder
Full Function Remote Control
Dimension	460 (W) X 86 (H) X 400 (D) mm
Weight	16 Kg (Net.)

Audio Space

Mini Galaxy One Stereo Integrated Amplifier ($899,-)
Output Power : 2 x 13W (Ultralinear-Class AB Push-Pull)
S/N Ratio : >88 dB
Output Impedance : 4, 8 ohm
Input Mode : RCA / USB (For PC, I Pod)
Vacuum Tubes : EL84 x 4, 12AX7 x 2

USB specs not available on the website so probably limited to 16 bits/48 kHz.

Chord CYAN Click Digital Integrated Amplifier

Unbalanced Input: 1 pair RCA phono

Balanced Inputs: 1 pair of 3-pin female XLR inputs

Digital Inputs: Coax BNC, TOSLink Optical, B type USB

Wireless Input: Bluetooth A2DP

Signal to Noise Ratio: -90dB all inputs

Frequency Range: 2.5Hz – 200kHz (-3dB)

USB specs not available on the website so probably limited to 16 bits/48 kHz.

Price: $8500 High Power Version (100W rms)

Bel Canto Design e.One S300iu

Integrated amplifier with 300 Watts of dual mono balanced power capability per channel.

USB specs not available on the website so probably limited to 16 bits/48 kHz.

Classe CP-800 US$ 6000.00

One of the inputs: asynchronous USB.

Full support of Apple’s iPod®, iPhone® and iPad® range of products.

According to the press release:

"the CP-800 can surpass the performance of conventional disc playback systems," said Dave Nauber, EVP of brand development. "A storage device like an iPod or computer can contain all the data of the original recording, so it has the potential to be an audiophile source," he said. "The challenge is to clock that data into the D/A converters at precisely the right time, which the CP-800 achieves through newly-developed recovery and clocking technology."

Available late 2010