So after procrastinating on what direction I should take on my set up at home I decided to make it simple. I saw the Sony SRS ZR7 at the local Sony Centre and was quite interested in it. It can stream wirelessly via a pc, chromecast, Bluetooth, via usb and also with a 3.5mm audio jack. So after a few Walkman sales I had the funds to get one Using the SB 500 tape selector I have the cassette deck, Fiio X5 player and the SRS ZR7 connected. I can record to the deck and monitor the sound through the speaker or headphones. I know this is not ideal for everyone and yes I would love to have a separate amplifier and proper speakers but that will have to wait until I get more space in the study. For now this is great for me. I can chill out with some tunes via my PC while I work or Bluetooth via my Iphone or throw in a cassette. The sound from this speaker is quite good. I can adjust equalizer settings via the SongPal app on my Iphone too.
That is a real mixture of old and new with 38 years between the tape selector and the speaker. https://www.hifiengine.com/manual_library/sony/sb-500.shtml