2. analog
  3. 166647-2693

Running LOMC with MM (47K) loading

This is the way I run my Zyx 4D and my Benz Ebony L before it. I have a JLTi phono preamp which allows me to do this. I have been satisfied with this pre since buying it new. Yet I may be in the market for a new (Different) one. However some I have seen may not offer this ability. One that has great reviews also  has the loading and gain all tied together. Not sure about Herron but it may be out of production. Not sure about others. 
 
The question comes  with @Atma-sphere comments on loading and circuit stability. He contends that the loading  damps (stops) the cartridge cantilever from moving as freely as it was designed (my words) And it is better IF you can run with no loading. But that requires a stable circuit which not all have. Apparently my JLTi has a stable circuit because I have been running LOMC's this way for a 10-15 yrs. 

That said, should I require this attribute to my next phono preamp? And might I be better off to send the JLTi to Joe Rasmussen  (Allen Wright's partner) for upgrade to Pre and new Power supply?. That will be the cheapest and that is likely to be the step I take. However the question still exists. If the damping is as per Ralph's assessment, it would seem that the stability of the  circuit is of greater importance than the ability to have a lot of loading options with unstable circuitry. Another question, Is loading a band aid for a  circuit which is not at an optimum? I am not an electronic tech so I am not  looking to stir the pot but  for my own  understanding  Thanks
128x128artemus_5
speakermaster
738 posts
 
You load the cartridge to what sounds good to you on your system and every system is different it is not a band aid but a load as you like it type of thing but i have found that you load a mc at about ten times its internal impedance for best results on most systems.
atmasphere's avatar
atmasphere
11,817 posts
 
You load the cartridge to what sounds good to you on your system and every system is different it is not a band aid but a load as you like it
Its a band-aid in the sense that if the phono preamp doesn't have a problem with RFI injected at its input, you'll find that loading doesn't affect the sound nearly as much. So you'll be able to run with the stock 47K and it won't be too bright.
artemus_5's avatar
artemus_5 OP
1,940 posts
 
Well,@atmasphere, you have answered another question I had about whether loading is actually a band aid. Seems to be a natural progression. However I suppose it could also be an option for the customer who needs to tame their systems tendency towards brightness. At least that wa an early finding I had with some different components. Thanks
atmasphere's avatar
atmasphere
11,817 posts
 
However I suppose it could also be an option for the customer who needs to tame their systems tendency towards brightness. At least that was an early finding I had with some different components. Thanks
Its not always an option to seek out a phono section that doesn't have this problem! So loading will probably be a thing for the foreseeable future.


For me the big thing is ticks and pops. I don't like them. A phono section that doesn't require loading at the input is also far less likely to generate ticks and pops on its own, caused by a poor high frequency overload margin at the input of the circuit.
gakerty's avatar
gakerty
175 posts
 
I loaded several carts (from Lyra Delos through 3 different Benzs) at 47K through my Pass XP15.  Sounded clear and extended, and not "bright" at all.  TBH, it sounded almost the same at ~1K vs 47K.  Perhaps the Pass is one of those phono stages that's not that sensitive to loading.  I now have a Andros Deluxe II, which only goes up to 1000 ohms.  I leave it at that.  Sounds lovely and better than the Pass, but that's a different discussion.
More to discover