Cartridge loading

Dear @stereo5  : I agree with those two gentlemans, you need to test it at 200 ohms again and try to fine tunning the cartridge/tonearm set up at that loading.

In the other side your Technics tonearm is spot on with that cartridge due that its compliance is over 10cu, don't worry in this regards.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

Cartridge loading is for the benefit of the phono section, not the cartridge!

It prevents the inductance of the cartridge and the capacitance of the tone arm interconnect cable from creating a resonant circuit, by detuning it. The resonant circuit can produce noise (often RFI) that is considerably more powerful than the cartridge signal itself!


The problem is that the loading resistor also causes the cartridge to do more work- it has to drive that load. The energy to do that comes from the stylus in the groove driving the magnetic generator in the cartridge, so the cantilever will get stiffer and less able to trace high frequencies.

So less loading will open up the highs in some cases. The problem is if the circuit resonance appears, it acts as RFI injected into the input of the phono section. If the phono section is sensitive to RFI it won't sound right- hence the need for loading. OTOH if the phono circuit designer understood this problem, then no loading at all is needed since the phono section will have no problem with the RFI. A side benefit of a proper phono preamp design is you will also experience less ticks and pops, as these can be caused by stability problems in the phono preamp!


At any rate always go with the least loading (highest resistor value) you can such that the system has correct tonal balance. 

Now try 47K and work downward from that value until you’re happiest.

@lewm ........My cartridge loading choices for Mc are: 25, 50, 100, 200, 400 & 1000 ohms.

@chakster ........the cartridge is in a milled aluminum body which is very heavy and absolutely no need for the extra weight. The set up of cartridge is perfect, why would I set it up again to load at 200 ohms? If it is set up properly, it should not matter as loading has nothing to do with correct cartridge alignment. The dealer (Adirondack Audio) put a lot of time setting up the cartridge and also used an oscilloscope in the process. When I got home, I rechecked the proper weight which was still spot on.

I am very happy at 1K ohms, I was just kind of wondering why.

Dynamic compliance of your DENON DL-103 cartridge is 5cu @ 100Hz , convert it to 10Hz and it will be 8.5 cu - this is extremely low compliance if you don’t know. Look at the specs of your Denon to check it if you don’t believe me. To convert 100Hz to 10Hz you need to multiply on 1.7, so this is why the compliance is 8.5 cu @10Hz.

The do yourself a favor and measure tonearm/cartridge resonance with a Test Record to make sure about resonance frequency.

Any cartridge with such a low compliance require tonearm with over 30g effective mass, Technics tonearm effective mass is about 11-13g as far as i know.

If your aluminum body made by Zu does not require a sub weight then it’s not heavy enough to increase tonearm mass twice as much!

Actually using an SPU on Technics tonearm is a perversion just like using Denon 103 on this arm. It’s like making a truck out of sport car. But the SPU models at least have an Elliptical or Replicant-100 stylus tip while your Denon 103 is a CONICAL (worst profile ever in the history, dirt cheap and full of distortion while playing).

Technics tonearm is a killer with high or mid compliance MM/MI or MC, but with the low compliance cartridges you’re close to the extreme.

I love Zu Audio speakers, but i don’t understand why you bought their Zu Denon for your tonearm ? Better cartridges with the most advanced stylus profiles and cantilevers are even cheaper than Zu Denon which is $750 as far as i know ? Maybe with harsh horn speakers a rolled-off Denon sound will help, but in a normal system it doesn’t (imo).

You can experiment with different loading for sure to find what you like, but you can change your cartridge to something perfectly match for your arm, it must be a mid compliance cartridge (not extremely low compliance like your Denon 103 / 8.5cu at 10Hz or 5cu at 100Hz).