Demagnatize cartridge??

I doubt that the 304 was magnetized by the stylus gauge. Every MC, MM, or MI cartridge contains powerful magnets to enable it to generate a voltage when the stylus moves. It sounds like your stylus gauge is attracted to the cartridge's magnets (and MC cartridges have the strongest magnets of all).

I'd get rid of the gauge - I think it should be made of non-magnetic materials.

As for the hum, I don't see a connection. Low output MC cartridges like the 304 need a lot of gain. It's very easy to pick up hum with high gain.

IS the turntable ground wire properly attached to your phono front end? Are you sure the headshell wires are properly and firmly attached to the cartridge (my 304 seems to have small diameter pins - I had to squeeze the clips a bit to make them work)?

What kind of phono front end are you using?

BTW, I think the 304 is a great sounding cartridge. I'm running mine at 300 ohms right now, but am still experimenting.

Your cartidge is ready to go. A coil is open

Yag is right, you probably broke a coil lead when the cartridge slammed into the gauge. Was it a Shure stylus force gauge?

Thanks for your responses. Sounds like it was actually the cartridge magnets attracted to the gauge. I shure hope the cartridge isn't busted already :( The gauge is one I bought from an A'goner, but I don't think it's specifically for cartridges (a deal too good to be true at $40) I thought it would be more acurate being digital (one more reason for me to hate digital). I haven't used it since -- gone back to my Shure NON-digital (analog??) teeter-totter!

I'm using a Perreaux SXV1 phono preamp. I find it difficult to match to MC cart's by just using the manual's charts, so I usually email them for the suggested dip-switch settings. The settings they sent worked well for a Grado wood body I have but not so much for the Denon. I'm still waiting to hear back from them about other suggested settings for the DL304, or even some general loading guidelines to try to decrease the "hum" volume. (I'm still confused which specs. are for capacitance and which impedance?? The units that are written on the cartridge specs. never seem to match the units in the SXV1's manual!!)

I also have a Musical Fidelity XLPS phono preamp that is good for a quick set-up (I much prefer the detail of the Perreaux though). But the XLPS does match the DL304 without producing much "hum" at all. There are no manual settings that I can see on the XLPS, aside from MM/MC, so I'm guessing it does it internally (?)

The TT is well grounded to the phono preamp (I have also tried grounding it to the power supply/line conditioner) and I have well shielded cables from the TT box to the phono preamp (which I know from previous experience can be a problem). I will check the pin connections though.

I've been doing a lot of searching about this topic in general -- matching a MC preamp to cartridge -- but haven't come across anything too specific to this situation, so I really appreciate your input.

Sorry so long-winded!