I never heard of a tri-band router before. It's a misnomer because there is no third band, it just means it can handle 2.4GHz but will use two channels of 5GHz at once. There have been other routers in the past that used more than one channel but it sounds very selfish to use in a dense apartment/condo living situation.

Well luckily there is a massive chunk of 5ghz channels that nobody is using right now so i'm okay, and the routers that use the 2 bands of 5ghz actually will step down to only 1 if they see someone else stepping on either of them.

But just the fact that the higher end routers handle the extra congestion much better was more the point.

It's worse than that. There is a third band, 802.11ad running at 60GHz. But as you say "tri-band" actually means tri-channel.

Good point, they should be called simultaneous tri channel.

'Power Line' or similar adapters can work quite well in apartments. You can use it for a wired connection where practical, and otherwise have a couple 5GHz routers for a good wireless access.

Hm, I'm not quite that isolated, but I do live in a single-family home, so that might explain it.

If they haven't done so already, maybe we'll see copper-clad drywall or flooring for such environments ? Guess that would take down cellular service too though.

I'm just waiting for a standard which smartly reduces transmit power so they all don't need to shout over each other.

Reducing transmit power reduces interference, but it also reduces capacity since the received power (and hence the SNR at the receiver) is reduced! The Shannon limit on channel capacity dictates exactly how much bit rate (C=B*log2(1+SNR)) is achievable over a channel. SNR is a fundamental ingredient of this equation.

Also, copper is pretty expensive. A mesh of cheaper metal should do the job; might even be possible to tune it to the right frequency so you don't block cellphones, but I don't know