Pre-Amp is your Audio Video processor.
A receiver can be a preamp if it has enough outputs for amplifiers. In other words. If your receiver is a 5.1 system...then you need to have dedicated outputs for 5.1 channels so you can attach amps.

7.1 - 8 outputs.
etc.

Hope that helps.

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Denon 4308
M80x2,VP150,EP600,4xQS8