2. analog
  3. 132985-541

Feedback Problem

My analog rig is a VPI Prime turntable which HAD a ZU/Denon DL103 low output mc cartridge. It sits on top of my rack on a 4 inch thick air dried Maple platform. With this set up, I NEVER had any acoustic feedback. I had to send the cartridge out to Sound Smith for repair.

In the interim, I put a moving magnet cartridge on the turntable and did the entire proper set up over again. The Cartridge is a Vasari Gold MM cartridge that puts out 4.5mv. Everything else is the same, same platform and now I am getting acoustic feedback with the volume level not very high. Before any one asks, I am using the MM inputs on my preamp.

Do you think the greater output of the mm cartridge (4.5MV compared TO .3MV) is giving me the acoustic feedback? I won’t do any changes of location of speakers or TT as I’ll live with it until my other cartridge comes back but am I on to something here?

Kindly let me know,
128x128stereo5
yogiboy's avatar
yogiboy
5,724 posts
 
It might be the difference in the weight of the cartridges. That Denon is 14 grams!
stereo5's avatar
stereo5 OP
6,428 posts
 
I am wondering if the high output of the cartridge is amplifying the feedback to a greater extent? I didn’t hear it with the Denon perhaps because it’s output is so low it doesn’t amplify enough for the speakers to pick up?
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rauliruegas
13,101 posts
 
Dear @stereo5 : With the Vasari cartridge the resonance frequency between the cartridge and the 10 3D tonearm is just in the top " ideal  " frequency range: 12 hz, I prefer 10 hz but this is me.

You don't said in with frequency range you have that feedback that could be generated because that resonance frequency  value.

Now, your preamp has gain selections and for that cartridge you don't need more than 40db that understand is the lower position in your unit. Too much gain in the preamp can makes that the preamp goes to overloaded and even with the lower gain set up the preamp can be overloaded if thae cartridge output surpass the preamp overload margin.

Now, could be too that that cartridge and your VPI tonearm are not a well match but for me is dificult to say where is the problem.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.




stereo5's avatar
stereo5 OP
6,428 posts
 
Do you think the Dynavecter DV20X2L cartridge would be a better match for my 3D arm?
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