RX9 Standard (which is all you need for Music Rebalance) is actually usually about $400 and is on sale now for about $100 off.
It will go on sale for less than that if you wait though; likely Black Friday would be my guess.
tl;dr, never pay list price for music software, it goes on sale all the time. The sale price is the real price 
That said, RX9 is massive, massive overkill for just removing bass for doing covers.
Another potential tool for this, and much more affordable:
https://products.zplane.de/products/peel/
They also make deCoda which is supposed to identify chords, structure, etc, and it’s on sale for $34 atm
Maybe turn down the bass control of your amp?
FYI. Another vote for Moises (albeit for drums), after comparing many alternatives:
Well worth the money given all the other things it can do.
The amp doesnt factor in when recording through a DAI, which is what most of us do when recording covers.
What I find interesting is that all those tools use Spleeter in the background, yet they clearly sound different.
But none of them advertise that they have trained their own models to set themselves apart from the rest. So I assume they all use the stock spleeter models.
So I wonder where the difference is coming from? Different versions of the models? Some post processing secret sauce they are individually applying?
Interestingly, iZotope’s products that do this (RX9 and Ozone via “Master Rebalance”) also use Spleeter internally. So those online tools give you the same functionality.
But as Pam said, you buy the iZotope plugins for other reasons. Ozone is by far the best mastering tool I have found, I use it in every mix. I’ve never used its Master Rebalance even once
I hadn’t seen this one yet:
Lalal.ai
Used here to uncover the unexpected true bass line of Mustang Sally … with a great lesson showing a case where the approach note falls directly on the 1 ! Very fun.
I watched that video. Mark’s impressed with the tech. Seems to work well. Also, a surprising bass line underneath everything.
They claim to outdo Deezer. They use the same technique so presumably they think their training data is better.
I use Moises.
I can play around with it with removing bass, bass only or a variety of mixes (just bass and drum, bass and vocals).
All mixes can be downloaded as well.
Really useful for learning a song and once learned the bassless track is for playing along.
I’ve tried removing baselines with Reaper with ok results. After watching some Izotope RX demos on YouTube I have to say it looks really nice and I may just have to fork out the cash.
+1 for Moises. Free, easy to use, and fast
One of the things I’ve learned from playing around with a few of them is that it’s good to try a few different tools on any given song. Someone had mentioned Demucs, so I tried that and it worked better than spleeter, which I had been using (I just preferred having the local app vs uploading to moises). So, I figured I’d switch to Demucs. Next song I tried didn’t come out so well, so I tried it with Spleeter - the results for that song were better with Spleeter. So, I’d just say, be open to trying a few different ones if the results from your “usual” tool aren’t great.
OK, So I tried Roy’s method and in the Song Sweater Weather by The Neighborhood and I just could not remove the bass enough.
I’d looked up Moises a few months ago and they did not have an Android version out yet.
They do now!!!
I just tried it with Sweater Weather and Boyfriend by Dove Cameron and OMG! It’s like magic
It’s definitely worth the money, not only for removing or isolating bass from songs, but also for all the other tasks it can perform. $300.00 is not a lot of money, especially when you consider how much people on this forum spend on pedals and plug-in effects.
One of the side benefits of RX9 I’ve found, is the ability to isolate the drum track in a song, which is very helpful for learning the groove.
OMG I see now that Moises also now has a Web App so no need to do it on your phone!
Yes I’ll most likely spend the cash when I get back into covers. I think they are up to RX10 now right?
I just updated to RX9 less than a year ago when it was released. I haven’t heard about another update since then.