Reddit mentions of Technolink TC-716 6-Port Stereo Source Selector; Black or Silver, Your Choice (Black)

Here you go.

6 stereo ports that function as either input or output.

I have this, it works well. It's a heavy, solid piece of equipment.

This is a switcher I bought many years ago and still swear by. There's no noticeable distortion that I can hear and the 6 ports give you a great deal of expandability. I also use a JDS Labs OL Switcher, which also functions as a passive preamp that I'm also pleased with. I run the audio from my DACs into the OL Switcher and then into the TEC switcher to feed my amps. I've listened to my system with and without the two switchers/preamps and, as I said before, there's no noticeable distortion that I can hear. The OL Switcher is $45 plus shipping and it's worth it in my opinion. Schiit also sells a passive preamp called the SYS which functions like the OL Switcher but costs a bit more and features one less output. I don't own it so I can't vouch for its quality but I've heard it's fine too.

Hope this helps!

An audio interface, such as this, has volume control and DAC: https://www.amazon.com/Steinberg-UR22MKII-2-Channel-USB-Interface/dp/B017MVUAHM/ref=sr_1_1?s=electronics&ie=UTF8&qid=1541691184&sr=1-1&keywords=steinberg+ur22+mkii

Or, you can cobble something together like this:

• ART Cleanbox Pro - converts unbalanced signal to balanced: https://www.amazon.com/ART-CLEANBoxPro-2-channel-Unbalanced-Converter/dp/B003S7T49K/ref=sr_1_3?ie=UTF8&qid=1541691516&sr=8-3&keywords=art+cleanbox+pro
  
• Passive volume knob, such as JBL Nano Patch+ https://www.amazon.com/JBL-NPATCH-BLK-2-Channel-Controller/dp/B01I3B0OH6/ref=sr_1_1?ie=UTF8&qid=1541691621&sr=8-1&keywords=jbl+nano+patch%2B+compact+2-channel+passive+volume+controller
  
• If you multiple analog inputs, you can use this TCC TC-716 selector https://www.amazon.com/Technolink-TC-716-6-Port-Stereo-Selector/dp/B078M7S4G8/ref=sr_1_1?ie=UTF8&qid=1541691718&sr=8-1&keywords=tcc+tc-716
  
  That's a lot of work to make studio monitors work for you. I concur with others that a receiver plus passive speakers is a better choice.
  
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