Well of course you don't need lots of power with Pi's but then you already know that. So perhaps you do need the power. If so, a '70's reciever is just the thing if it works. Here's a 75 watt Marantz chosen more or less at random. Audiogon has been good to me but you MUST speak to the seller by phone to get the vibes.I have no conection to the seller and this is not a recommendation, just an example.