Instruction: Answer the given question by extracting information from the supporting document.

Input:
Question: Does this router have the ability to broadcast 2 separate SSIDs, without using a guest network? I want separate SSIDs for the 2.4Ghz and 5Ghz.
Document: That's incredibly impressive for the 5GHz network to have a greater range than the 2.4GHz network considering all the walls this thing is penetrating to get to my living room. I didn't even have to change the default Tx power from 80mW to get that (configurable up to 200mW)! Amazing.Bottom line: If you live in an area with lots of wifi interference, this router is your new best friend. If you live in a remote area and want a pain-free wireless router, this router is your new best friend.
I bought this router back in September of 2013 at a local Fry's Electronics. I have had non-stop difficulties when using the 2.4GHz network. Constant drop-outs, slow speeds, and unavailability plague this device, making it unusable. The 5GHz is nice but considering only two of the fourteen devices I have at home are 5GHz compatible, its useless.Now before some Asus agent responds to this, I have update the firmware, changed the bandwidth, and done everything you have already proposed. Asus needs to stop trying to hide the fact that this router is plagued with problems that makes it useless for 9/10 devices that don't have 5GHz compatibility.
I originally purchased this router in January 2014. I was looking into upgrading from my old Belkin Wireless-G router and was planning to use the included USB 3.0 port to coordinate network backups in my home. However, upon using the router on my iPad or Laptop, I noticed that I got speeds less than 1 mbs! I first thought that this was a problem with the devices themselves, but after using multiple devices, and setting the iPad to use the router's 5Ghz range, I found out that the underlying problem came from the 2.4 Ghz range itself.
I read some of the negative reviews on this router and was reluctant to purchase, but I felt it worth the try for the great price (I also got a $20 rebate! )I had to install the new BIOS update to get all the functionality to properly work, it does seem that they released it before it was totally working. I am using everything, 5Ghz 802.11ac on exclusive 80 band, 2.5 Ghz on a separate ssid, USB 3.0 port with a hard drive installed.It works great and I have both PCs and Macbooks.
All I can say is wow. I don't typically leave reviews for products, but this one needed to be reviewed. I recently switched from a Linksys e1200v1 after constant connection drops in an area with high 2.4GHz interference. I hooked this router up to a Sony Vaio Pro 13 with an Intel 7260 wireless chip via the 5GHz network and was immediately blown away at the speed and range. In the area of my apartment where I typically got a dropped connection, I now have a full connection, ping times have decreased to nearly the same as my hardwired desktop, and internet connection speeds have nearly tripled due to the increased range and power of this router.
My netgear WNDR 3400v2 would lock up once a week or bi-weekly which required a reboot. No problems with this ASUS RT-AC56U in that department. The deal breaker here would be if you need to use the 2.4GHz 802.11N capabilities with the RT-56U as it is simply broken. I am using this router with 2.4GHz N disabled, because I use 5GHz AC normally. I also use my older netgear WNDR 3400v2 as an extra AP with 802.11N enabled on that - so the broken 2.4GHz N on the ASUS doesn't really affect me like it might others.
I was blown out of the water how fast this thing was. AC is a huge jump over N especially on 5GHz. Range is good (not great) as people make ASUS routers out to be but worked better than anything I had before. With a Rosewill USB 3.0 Wireless Dual-Band Adapter 1.2Gbps my network connect was practically as good as LAN. This router has just about everything a home user could possibly want. I especially liked the fail-over/load balancing feature. On first use it even updates its firmware.About a week ago, latency skyrocket and I began to drop packets like crazy.
Laptop connected via intel adapter 802.11AC @ ~ 800mbit on the 5GHz band+ Newest firmware has feature to disconnect clients based on signal strength (useful for multi AP setups when you want the device to pick up a stronger signal with the same SSID)+ intuitive web interface with tons of options, only slightly less than say DD-WRT but all essentials plus a few extras are present in the ASUS firmware.Cons:- 2.4GHz frequency, more specifically the 802.11N implementation is seriously FLAWED and not usable until ASUS fixes the issue.- Clients drop connection on 2.4GHz 802.11N connection after about ~50MB of data is transferred.
Works good on the 5ghz band, but the 2.4ghz is disappointing for devices that limited to wireless N standard. Using the 2.4ghz band, it normally connects at 5mps....VERY DISAPPOINTING ! !
I've been running this router for 7 months and have the following conclusions:5Ghz works good. Both N and ACRouter software has improved with each release, in usability, features, and speed.Asus is updating frequently although they made little progress on the 2.4 issues.With regards to the 2.4 issues:Back in November, 2.4 was completely unusable. My devices could hold a connection but transfer speed was almost zero. Literally less than 1 KB/s. 7 months later, using firmware 3.0.0.374.5656, speeds are improved but I can only reach ~250KB/s transferring from a desktop to my laptop.
Answer: I have mine configured exactly like that. And that functionality stays even if you switch firmware.