The Archer C9 is not currently Wi-Fi Certified. But that could change, since the C8 wasn't certified at the time of our review and now is. We tested using our V8 Wireless test process with 3.15.27 Build 20141015 Rel.38077n firmware. A quick WPS test using a Win 8 client prompted for a WPS pushbutton connection on both bands. Pushing the C8's WPS button quickly completed WPA2/AES sessions for both bands.
Both radios come up with unique SSIDs and auto channel and auto bandwidth modes. For throughput testing, the router was first reset to factory defaults and Channel 6 and 20 MHz B/W mode set for 2.4 GHz and Channel 153 and 80 MHz bandwidth mode for 5 GHz. A WPA2/AES connection was used for all testing.
The C9 was centered on the octoBox chamber turntable. It was propped up to get a more vertical orientation for the antennas to keep the antennas centered during rotation. The front of the router was set as the 0° test position as shown in the photo below.
TP-LINK Archer C9 in test chamber - 0 degree position
The Benchmark Summary below shows the average of throughput measurements made in all test locations.
TP-LINK Archer C9 Benchmark Summary
To put these average values in perspective, compare each of the four average throughput benchmarks for all AC1900 routers tested with the latest V8 process. The C9 is near the bottom of the group in all comparisons.
Average Throughput comparison
For 2.4 GHz downlink, the C9 runs pretty much with the pack, albeit on the low side. Range is pretty good, with the connection lasting all the way out to 60 dB. The other three routers, however, stay connected all the way out to the benchmark maximum of 63 dB of attenuation.
2.4 GHz Downlink Throughput vs. Attenuation
The 2.4 GHz uplink plot shows the C9 starting with the ASUS and NETGEAR, but jumping below the other products from 18 dB onward.
2.4 GHz Uplink Throughput vs. Attenuation
The 5 GHz downlink plot shows a much larger difference in performance for the C9. It starts out lower than the other three products, stays there throughput the test range and disconnects after 36 dB—the same as the ASUS RT-AC68U.
5 GHz Downlink Throughput vs. Attenuation
For 5 GHz uplink, the C9 again runs below the pack and disconnects earliest.
5 GHz Uplink Throughput vs. Attenuation
I doubt the Archer C9 will repeat the success of the Archer C7. Like the C8, it doesn't have a price advantage, being priced around most other AC1900 routers in the $170-ish range. (I was shocked to see Linksys' WRT1900AC still up at $250!)
More to the point, however, the C9 just doesn't have the performance to merit either trading in your current AC1900 router, or choosing it as your first one. The Router Ranker Performance Summary below shows a #5 total rank with low ranks for both wireles throughput and range. Storage throughput isn't anything to write home about, either.
TP-LINK Archer C9 Ranker Performance Summary
The good news is that TP-LINK fans looking for higher performance can wait for its just-announced AC2600 and AC3200 class models. But if TP-LINK is going to give up its traditional "value priced" advantage, it will have to step up its game in both performance and time-to-market.