Hi McGarvey,
Welcome to the forum. These are the Specifications for the Polk Audio 10a speakers:
Specs:
Driver Complement--
Tweeter
Quantity 1
Diameter 1" (2.54cm)
Type Polk SL1000
Midrange
Quantity 2
Diameter 6 1/2" (16.51cm)
Subwoofer
Quantity 1
Diameter 10" (25.40cm)
Type sub bass radiator
Total Frequency Response 25Hz - 25kHz
Upper -3dB Limit 25 kHz
Lower -3dB Limit 37 Hz
Nominal Impedance 8 ohms
Efficiency 89 dB
Recommended Amplifier Power 20-250 watts per channel
Cabinet Dimensions
Height 28" (71.12cm)
Width 15" (38.10cm)
Depth 12" (30.48cm)
You can get data on the reciever here
Onkyo HT-R330 Receiver
It looks like it was originally supplied as part of a Home Theater Package. It's got decent power => 100 watts per channel min. RMS at 8 Ω, 2 channels driven from 1 kHz with no more than 0.9% total harmonic distortion. So it should handle those Polks no problem => just make certain the cables are connected correctly (Red to Red / Black to Black) to keep the speakers "in Phase" or your bass response will suffer. Make certain the volume is turned down to minimum before turning on the receiver.
As for input sources, you describe a USB audio interface in use now on another system. Please advise model number and what you use it for. Most Motherboards in desktop PCs (not all Laptops) usually have (and all recent separate Audio Cards have) Line Out sound outputs, and /or coaxial or optical outputs. The HT-R330 can take any or all of these. Are you planning to connect a DVD or BluRay Player? Please describe what you'd like the system to do and the folks here will give you as much help as you need.
That being said, just make sure you have fun with this system, but don't crank it up too loud as those vintage speakers may complain, and you can damage your ears for life with sustained loud music.
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