Is there any way to connect a record player (RCA outputs) to AirPlay speakers?

I've got a very simple situation, which is: I have a generic record player with a preamp and RCA outputs (red/white). I have a pair of speakers connected to an old Airport Express, one connected to a new Airport Express, and an Apple TV.

Can I make the record player Do A Sound in the AirPlay-connected speakers? Options I've considered are:

• A Raspberry Pi, but the software side of it may be more trouble than it's worth


• Connecting the record player, using an adapter, to my iMac, and then using Rogue Amoeba's LineIn to capture input, and transmit all audio, using Soundflower and Porthole, to AirPlay. This worked, but the lag between different speakers is considerable. Also, I'm using three separate apps for a task I should be able to do with a small box.

This doesn't seem like that maddeningly difficult an ask, but so far I've come up with nothing that works as an AirPlay transmitter in the same way as, say, iTunes. I can get this amp for cheap: http://ift.tt/1rnu75i but I don't understand if it can transmit as well as receive AirPlay streams. Halp?