Cartridge Loading.....Part II


I read last night the below noted discussion with great interest.  It's a long post but worth the effort and I found it interesting.

It started me thinking about the amount of loading on my moving coil cartridges.  Years ago I purchased my first MC Cart, a very nice Benz Micro Glider, medium output of 0.5 mV as I recall.  At that time I inquired about loading here on Audiogon.  I was convinced, via discussion, by another member, that 300 Ohms was the magic number, so I thought.

Time moved onward and my second MC Cart is currently a Lyra Delos, again medium output 0.6mV.  Both carts had Boron cantilevers', 6 nines oxygen free copper coils and line contact diamond stylis.  When I set up the Delos I did not change or even consider 'loading' changes.  That was a grand mistake.....

Well, thanks to this specific thread I started to second guess myself . (you can do this when retired and more time is on your hands....)

My take from this recent thread is as follows.  Load at 100 Ohms or at 47K Ohms with a quality MC cartridge.  I opened up my Conrad Johnson EF1 Phono Stage this afternoon.  Found it set at 500 Ohms loading.  100 Ohms is not an available setting.  Damn...All these years I've been running the wrong loading, and on two carts, back to back...  I don't recall why I set the loading at 500 Ohms.  Faulty logic.

I reset the loading to 47K, buttoned things up and called the wife in for a listening session.  Sure as heck both of us noticed the highs were crisper and more 'apparent' than in the recent past.  Not a huge difference, but yes, a difference..  Hard lesson learned!

So, you smarter folks on this site might banter amongst yourselves, but in reality there are those of us, behind the curtains, reading and listening!  I just wish I hadn't wasted all those years listening to the incorrect load setting!

Ending with a sincere thank you very much!!

Lou

 

quincy

Showing 3 responses by mijostyn

Ok guys, I'm getting dizzy.

@rauliruegas , I already have that test record!

Channel D has received my wire transfer ($500 credit) and A friend says the Platinum Signatures will arrive any day. I might also get an Ortofon Verisimo., teeter tottering on that one. Since I can run the phono stage 4 different ways and I can record records to the computer I will be able to make 192/24 files of all the results which I can download so everyone can judge for themselves as long as your system can play files. If not then GET WITH IT. Digital is hear to stay (spelling intended). It allows you to do cool things you can not do otherwise and share the results with friends. 

@rauliruegas  I have no idea what is better but I will figure it out and I will be happy to email you the files so you can compare. Then you can tell me!

@intactaudio , I think miss-tracking distortion and IM distortion are two separate but additive issues. 

There is a big difference between normal cartridge loading and an impedance approaching zero. This is all conjecture (theory?) at best. I have not seen a study done on tracking ability vs cartridge loading. I have seen distortion measurements on the same cartridge run voltage mode vs current mode and distortion is certainly lower in current mode. I think this is me agreeing with @rauliruegas again. It is indeed a strange world. 

@rauliruegas , I will run the Seta in both modes with and without digital RIAA correction to see if I can tell a difference but it will be a while. Rob has told me my phono stage is 4 to 5 weeks away. I still have not cornered a cartridge yet. All the cartridges I am interested in are "special order" and it seems nobody is making anything at the moment.  

@rauliruegas ,Don't worry friend, there is now a front panel switch that allows you to switch back and forth, no more jumpers. The Phono Stage has a 5 MHz bandwidth. I did order an ultra accurate RIAA board but I am already set up to do digital RIAA correction. 

Who came up with the thought that cartridge loading affected tracking? That is rather silly. Once you get to an extremely low impedance input there is less back EMF for certain. I have seen oscilloscope tracings showing this. I am not an electronics engineer. I can only rely on what I read and see and have to assume it is not marketing BS. I sort of doubt Rob Robinson is the type of guy to BS his customers.