Demagnatize cartridge??


My Denon 304 seems to have been "magnatized" by a new stylus force gauge I am using -- the gauge just "sucked" the cartridge down to it. Now the cartridge magnetic attraction. Does anyone know if this is harmful to the cartridge or playback? Is it possible to de-magnify a cartridge? There is also an excessive amount of "hum" coming through, even though I have tried different loading configurations. Could these problems be related? I appreciate your help!
cekiv
Ghostrider -
I think I got mine from the same German dealer. Nice to deal with. The digital scale was the first I used with the DL304, so I had not played it before it "crashed".

I'll check the pins again.

Thanks!
Cekiv,

There's nothing wrong with "digital" scales of course. They are certainly more accurate than the Shure teeter-totter, even a non-magnetic one. (Some Shures are magnetic and some aren't. This is because Shure failed to accurately specify the right kind of SS for different production runs. Some SS is magnetic, some isn't.)

To use your new scale safely you need some kind of step, so that you're not dropping the cartridge directly onto the magnetically attractive platform. This confers the additional benefit of letting you weigh at record surface height, which is also more accurate. The doohickey you need can be DIY'd from nearly anything. Here's a photo of one (overly elaborate) solution:

http://www.simplyblack.net/WVC/tools/scale.htm

My step is simply a 1" wide length of brass strip folded into the appropriate shape. Others cut up a credit card and glue the pieces together, which seems like an excellent idea for audiophiles! ;-)

Doug
even if the attraction (of the Shure gauge is not catastrophic, it can throw the readings off
Good point. It does, invariably so. You have to resort to tricks (side-ways readings, etc). Oh well...
You guys seem to have it under control. but just a word of caution about the Shure "teeter-totter" stylus force gauge: although it's stainless steel, it still has magnetic properties and can be attracted to the very strong magnets in some (most?) MC cartridges. And even if the attraction is not catastrophic, it can throw the readings off.
Cekiv - I have my 304 mounted on an overhauled Yamaha PX-2. The cartridge came with 2 sets of screws, one pair too short and the other too long. I used the too-long screws of course.

I had no problem balancing the cartridge and setting tracking force to 1.2 grams, though the cartridge semed pretty light compared to the Shure Ultra 500 I had mounted previously. The balance weight is pretty far forward but not at the end of its travel, which is a good thing.

Surprisingly it tracks very well. I wasn't sure what to expect with the Denon - the Ultra 500 is a tracking champ.

As I mentioned, the headshell clips were loose on the cartridge pins. Did you notice this? A good bump could dislodge a connection if you didn't crimp the connectors for a snug fit.

My phono preamp is a Pass X-ONO which is dead quiet with this cartridge even though it's set to maximum gain.

Did the hum start after the collision with the scale? Does it occur in both channels or just one? When you mounted the cartridge, did you do anything to prevent electrical contact between the cartridge body and the headshell?

BTW, I recently bought the cartridge new from ebay from a German dealer (I'm in US). It came within a week of purchase in unopened condition - no problems. He had a few more in stock if anybody else wants one.
Ghostrider45, on a side note, did you have any difficulty mounting the DL304?

The 304 is too light to mount without a headshell weight to my VPI JMW9 (even after I upgraded to the Signature Series). So I use the headshell weight, but THEN none of the screws I have are long enough. So I go to ACE and find some longer screws that are really too thin, but they work. NOW, with the cartridge in the proper position, it's heavy enough that I have to move the counter-weight midway back on its tonearm post, which isn't ideal for this sort of tonearm -- it's better to have that weight as far forward as possible. BUT take the headshell weight off, use the proper screws, and NO DEAL -- can't get enough tracking force!!! It's a genuine Catch-22!!

Just wondered what your experience was...
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!
Yag is right, you probably broke a coil lead when the cartridge slammed into the gauge. Was it a Shure stylus force gauge?
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.