Contrary to the answer that states "soundbars are not designed to work with receivers" - a soundbar can, generally, be 'plugged in' to a receiver preamp input(s). Since soundbars are almost uniformly powered via their own amplification you should not plug the already amplified source (in this case a soundbar) to another amplified source. The suggestion someone "...use the tape record out of the receiver to feed the aux analog input on the soundbar" is simply wrong and could damage your equipment for the reason I mentioned.
Lastly, a soundbar can connect to a TV in any number of ways HDMI, HDMI(ARC), Optical input, mini-plug, RCA jack etc. it just depends on the connections available to you and there are adaptors that can be purchased at very little cost for a range of connection possiblities.
...you might even, depending on your TV model, be able to use an audio out from the TV as well as the 'older JVC receiver' and switch between them (either automatically or manually via self-selecting the applicable input).
The advice you were given earlier was simply too incomplete, too bad, or entirely wrong to not post a comment clarifying some of this, given the limited information available, for others.