If you did not check the resonance frequency with a test record then you didn't

Don't get me wrong. This has nothing to do with your DIY efforts. And nothing to do with actual ringing of the arm.
It just has to do with how your new arm compliments your cartridge.

With commercial arms, you can put your cart's compliance and the effective mass (not weight) of the arm on a calculator and get the resonant frequency. Your goal is to put this frequency at ~8-12Hz. This will make it high enough to not let them resonate with rubble, and low enough so that they do not resonate with bass from your music.

With a DIY arm you have to check it with a record.

If you do not have a test record, an indication that you have an issue with amplified rubble is if you see the cones of your speakers wobble.

But since you decreased the mass, chances are that you are closer to bass frequencies. Check it if you have more issues with jumping/skipping on bassy passages