OK. I got scared while waiting for the Creative Sound BlasterX Katana to arrive. When it showed up I considered not opening the shipping box but I finally did. I had to find out what my buddies were talking about. Now it's all hooked up and running and I'm extremely pleased.
I first tried it using the headphone jack. While it already sounded better than my monitors onboard speakers it was very much stereo + the added sub woofer of the Katana.
I then reread the instructions that came with the Katana which claimed the Katana's onboard sound card would create 5.1 out of a USB connected Mac or 7.1 using an optical drive connection to a home theater system. I don't have a home theater system anymore so I couldn't verify the 7.1 claim. But, when switching from the headphone jack to the USB connection the difference in sound was extraordinary. I had my wife sit down in front of our setup to see if she heard the same things I was hearing. She heard exactly the same thing. Please note the next paragraph about using the USB connection.
The issue I ran into when switching from the headphone jack to USB was the application Boom 3D. I've really loved this app because it makes crappy onboard monitor speakers sound much better and that's what I was working with. But, as long as it was downloaded to my Mac, whether on or off, my Mac Mini wouldn't let me pick any other USB output. I figured I could redownload Boom 3D if needed so I ditched it. The gambit worked. All other options for sound output became available.
The Katana offers five different types of sound including "Theater", "Concert", etc. What I found was the "Gaming" setting kicked everyone else out of the park. ( Note* I'm not a gamer. I'm 64 years old. I have a huge iTunes library that includes 100's of my favorite albums ranging from the 1930's to date). Still, With gaming selected on the Katana and a USB connection being used to connect the Katana our Mac mini the sound outputted was most definitely 5.1. Both I and my wife could distinctly hear "Center", "Right", "Left", "Far Right","Far Left" and superb Sub woofer bass tones from the Katana sub under the desk.
Now ..... on the negative side. Creative does not, at this time, offer software compatible with Mac Mojave. The software they offer for both PC and partially to Mac OSX is a huge addition to what the Katana can do. Some of the customizable features are astounding. I'm already more than happily impressed with the results of my Katana to Mac mini via USB connection but I would certainly love to have the addition options provided to PC users. We should get a write in campaign going to Creative to get them to create software compatible with Mojave. This product has set me back on my a.. . iTunes sounds fan freakin' tastic through the Creative Sound BlasterX Katana. Plus. It works for a wide range of musical styles in "Gaming" mode. I think "Gaming" mode should. be labelled "ITunes" mode. I listen to jazz, blues, folk, country, rock & roll, progressive and instrumental modern guitarists, (both electric and acoustic), while my wife is a "Heavy Rock" / "Vintage Metal" / "Modern Metal" mega fan. Our current setup works perfectly for both of us.