I pulled those out of my closet and gave them another go. There’s no way those things block 32dB. The GKs are rated at 29dB and easily double the isolation if not more. It goes back to numbers meaning nothing. I’ll buy into the Sennheiser blocking 32dB at one narrow frequency range, but so far as blocking mids to lows are concerned. Nowhere near 32dB.
I’ve taken them apart before and there’s nothing between the driver and the hard plastic outer. While most reviews rate them well, most drummer reviews say they are a no go.
We all hear differently though, but I found the Vic Firth headphones lacking in low end isolation too. They were great for mids and highs though. Lots of drummers like those, so my recommendation to the OP is try the Vic Firth’s. Cheaper too.