I am looking to buy a Samsung HWj450 wireless soundbar. Are these 2 products compatible?

Question edited for a lot more clarity.
Question moved to a Samsung Sound Bar category.

It is wireless and uses a non proprietary system according to this, so No.

https://eu.community.samsung.com/t5/audio-video/ps-wh550-sub-woofer-compatibility/td-p/3627892

https://www.google.com/search?q=Samsung+ps-wd550+sub

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Sound drops out from the wireless subwoofer. The sound on your wireless subwoofer can drop out if there is interference or a physical obstruction between the soundbar and subwoofer. Make sure the subwoofer is within range of a good signal of your soundbar, and that the issue is not with the source audio.
https://www.samsung.com/us/support/troubleshooting/TSG01109876/

depends on the connector types and what type of wireless signal

have you asked Harman Kardon?

Because your TV is not Bluetooth-enabled and you are trying to connect it to a Bluetooth-enabled soundbar via Bluetooth. There are other ways to connect your TV to the soundbar:

1. analog AUDIO OUT (L/R) of your TV to the AUX IN on the soundbar (use a 3.5 mm.-to-RCA audio cable).
2. Optical OUT on your TV to Optical IN on the soundbar.
3. HDMI port to HDMI port (this may not work if your TV is not ARC compliant you have to try).

You get better sound quality with option 2.or 3. (if this one works for your TV)

Here is the link to download the soundbar's User Manual for help with the connections:

http://downloadcenter.samsung.com/content/UM/201411/20141114104022428/HW-H450-ZA-1114_Bookmark.pdf

Here is a link to your product description. When you get to the web page, click on the "Manual" tab to read the user's manual to find out how you can connect your soundbar to your TV.
HW H450 Wireless Audio Soundbar Samsung Home Audio

I presume you need link the Wireless Subwoofer to tour Soundbar.
Here are instructions:
How To Link The Wireless Subwoofer To Your Soundbar HW Models Samsung

How i connect to my tv

Use a high speed HDMI cable form the TV to the sound bar. HDMI cables carry sound as well as picture signals. Refer to your TV's user manual http://www.hdtvsolutions.com/pdf/52527-62528.pdf
and the Samsung product support page http://www.samsung.com/us/support/owners/product/HW-F450/ZA for assistance

What if the soundbar is Bluetooth? Will I still be able to use that function and connect the active soundbar to the tv (Bluetooth) and connect the av receiver for other surround sound speakers? (they are pre-wired in the walls in the apartment I moved into)