As is our practice, wireless performance was tested using our standard wireless test process, which uses an AC1750 class test client. This is the same as all other AC1900 class routers tested to date, so results are directly comparable.
The WRT1900AC is Wi-Fi Certified for 802.11a,b,g,n and ac. It defaulted to Auto channel mode on both 2.4 and 5 GHz radios upon power-up. Both radios defaulted to Auto Channel width on power up. The router comes with unique 2.4 and 5 GHz SSIDs set, so you don't have to change anything to connect dual-band clients to the desired band.
WPS appeared to be enabled on the 5 GHz band only because only it popped up a WPS pushbutton prompt when a Win 7 client attempted to associate. The WPS pushbutton test passed, completing quickly with a WPA2/AES connection. There does not appear to be a control to set the band that uses WPS or to cause it to be used on both bands.
I then ran 40 MHz Coexistence and Fat channel intolerant tests. Setting the Fat Channel intolerant bit caused the router to immediately fall back to 20 MHz rates for a test pass. But it did not resume using 40 MHz bandwidth when bit was cleared on the test client. However, moving the router to Channel 8 with another network on Channel 11 for the 40 MHz coexistence test did not cause the WRT1900AC to immediately stop using a 40 MHz channel width, so the test failed.
For throughput testing, the router was first reset to factory defaults and Channel 6 was set for 2.4 GHz and Channel 153 for 5 GHz. 20 MHz bandwidth mode was set for 2.4 GHz and 80 MHz mode was set for 5 GHz. The test client was connected using WPA2/AES encryption.
The router's antennas were positioned 8" from the chamber antennas in the 0° and 180° test positions. Because of the WRT1900AC's width and the tight quarters in the test chamber, the closest antenna in the 90° and 270° positions was more like 6 to 7 inches from the chamber antennas. The 0° position for the router had the front facing the chamber antennas.
The WRT1900AC's Benchmark Summary below shows the average of throughput measurements made in all test locations. I won't spend any time analyzing this, since the Router Ranker does a better job and we'll look at that in the Closing Thoughts.
Linksys WRT1900AC Benchmark Summary
Moving right to the profile plots, I pulled three other AC1900 routers into the comparison: NETGEAR R7000; ASUS RT-AC68U; and Linksys EA6900. I didn't bother comparing the one other AC1900 router tested, TRENDnet's TEW-818DRU, because it performed so poorly.
The 2.4 GHz downlink profile shows the WRT1900AC starting out with higher throughput than the other three routers and no dip at the mid-teen attenuation values. But even if you discount the deviation from the curve at 39 dB, the WRT still declines in throughput slightly faster than the other products. Since it is the lowest of the group at the 60 dB point we use for range ranking, it gets the lowest ranking for that benchmark.
2.4 GHz Downlink Throughput vs. Attenuation
The 2.4 GHz uplink plot shows a tight clustering of all products out to 27 dB, then the WRT once again falling off the fastest and again earning the lowest range ranking of the group.