Buy High Pass Filter or KAB RF1?

The KAB RF1 will do what you want.  The high pass filter won't  I own the KAB, it got rid of every bit of the feedback without altering the bass.  It uses all audiophile graded parts inside.

My preamp has both a tape loop and processor loop.  I run it through the processor loop.

@craigert...……………………………...

Everyone here will tell you to relocate the turntable, put it on a maple, slate or granite platform, or tennis balls, mount  turntable to a shelf on wall, change cartridge, etc.  I tried all that, blowing money on 3 different platforms, new cartridge and I STILL had to buy the KAB Rumble Filter.  Save yourself the grief and expense that I did and get the filter.  I can't hear  a difference with and without it and I am feeding it expensive cables to boot.

@yogiboy...……………………………..

Good call, had forgotten about those.  It's cheap enough, I would give it a try.