​103R vs 103

Of course this is my opinion but all the information is valid and you can bring up my sources by clicking paragraphs.
Your ears are also valid information tools try what is being suggested and you will understand the true value of proper loading.
Now for the answers as to what was going on and the verdict of 103R vs 103.
First I have some information about transformer input impedance (the load for your cartridge if using a SUT is the input impedance of the SUT) most of it gleamed from Vinyl Engine (to use this link just click on text:  ​​http://www.vinylengine.com/step-ups-and-mc-cartridges.shtml ) and common sense that you should be aware of.
Some SUT's have a higher input impedance, but less gain, and may work for your application but generally the highest you will find is 470 ohms (20 db of gain) and this is very very rare, not the norm.
The input impedance of the SUT is the LOAD for the cartridge period. The Cinemag 1254 I was using can be 37.5 ohms or 150 ohms depending on configuration I was using the 37.5 which had the most gain.
This low input impedance is the load for your MC cartridge and putting a load across it will only lower the impedance (impedance and resistance or ohms are all the same thing) further. This low resistance is NOT loved by the Denon MC cartridges although Denon themselves say to load at 100 ohms and sell a SUT!

I have found that the 103 is less susceptible to loading issues than the 103R and I believe this to be the root of any and all debating as to which sounds best.
At first (as I mentioned earlier) I prefered the 103 to the 103R, all because of my loading impedances, one being fixed @100 ohms and the other being 37.5 ohms of the SUT.​

When I first started playing the Denon cartridges (about 5 years ago as I got back into vinyl)  I thought the 103 sounded best, authoritative, detailed, dynamic and a wonderful overall balance that lets music be music. Who could want more and yes I did own a Koetsu Black and Rosewood among others before I got out of analog about 15 years earlier.
The 103R seemed to have wispy or vapor like images, the sound was thinner and tilted towards the top frequencies although there seemed to be slightly more detail.

Let me explain what was going on.
I had two Moving Coil (MC, MM is for moving magnet) phono's.
My first (MC) phono had a fixed 100 ohm load resistor as many or most MC phono's do unless they have provisions for changing the load.
My second was a MM stage along with Cinemag 1254 SUT's.
Now a little more history before the verdict.

Enter the Paradox Pulse phono, passive RIAA, double regulated power supply, external RCA loading provisions so you can use any load you want, the only parts in the stereo signal path are my circuit board, 3 matched sets of LSK170 Jfet, 3 sets of coupling capacitors, 1 set of Audio Note Silver Tantalum resistors ($50- each), my wire and RCA jacks for 70 db of ultra clear gain.
This new phono (it is an old design and some companies sell their product with this circuit for over $30k) is extremely good and has put everything (including every highly praised tube phono it has been pitted against, there has never been a good sounding 12ax7 vacume tube made) to shame that has crossed it's path including a $40k phono from a company I don't wish to mention here.

Just a note;

When using a new 103R/103 always allow 100 hours before serious evaluation as that is the minimum length of time for proper breakin. They will start sounding good at 50 hours.
Do not have new cantilevers (Aluminum, Boron, Ruby, Sapphire etc...) and diamonds (elliptical, line contact, micro ridge) installed until break in process is complete I also recommend potting before new cantilever and diamond to avoid possible breakage.

The verdict;​
The 103R is a clear winner. It is all because of the purer wire and the lighter coils, as compared to the 103. With proper loading applied both cartridges like 400 plus ohms with the 103R's ideal load @ 600 to 700 (I use 690) ohms, only your ears know for sure.
The 103 will perform very well (better than the 103R with a 100 ohm load) without it's ideal load, so you can enjoy a 103 cartridge even without its perfect settings. Many people have proven this true throughout the years. The Denon 103 was introduced in 1962 and tens of thousands have marveled at this wonderful cartridge with all manner of circuits, loads and SUT's.
What do I think of the sound? The Pulse Guard R (103R) improves on every parameter and eliminates all of the bad and or distorted sounds that come from a stock 103R or 103. By the way if you do not remove 90% or more of the plastic surrounding the motor assembly you will NOT achieve what I am talking about, which is why wood bodies and others are vastly inferior to the Pulse Guard when trying to extract ALL that the 103's can do. Wood bodies press fit into place or tape or use a dab of glue or screw leaving all or most of the plastic I am talking about. There is also no extra damping or encapsulation to eliminate these distortions. I have even potted wood bodies in an effort to reach the full potential with the micro dampers and they still fall incredibly short of the 103's maximum potential.  I also think that most MC cartridges on the market would improve if they damped and encapsulated their motors and yes I am referring to $10k cartridges. Leaving the motor assembly exposed to the environment is not the way to get the best sound possible from anything much less tiny moving coils in a magnetic field, why do you think so many manufactures use various materials (wood, rock, various metals screws etc...) to try to "tune" the sound. Just eliminate the issues and you're miles ahead.
 I am also a fan of holographic imaging (see Jason Serinus comments in Awards section) as real music has when at an event, if a cartridge can't image properly then it is useless to me. An actual review is in order but that is for another page and another time as I prefer for you to tell me what you think about the Pulse Guard's performance.

Now I am only concerned with the best sound I can get from my records and the value of a component. This is the reason for the Pulse Guard body its removal of all the excess plastic, encapsulation, micro damping and the Sapphire cantilever with Micro Ridge diamond (SMR) $1100-. I would like the Pulse Guard R SMR to sound as good the best cartridges available like Ortofon, Benz Micro, Koetsu, Ikeda, Clearaudio, Soundsmith, Shelter, Lyra, Air Tight, etc... to only name a few and the SMR stacks up very well with the best of these. I go to Audio shows regularly (I bring great records so my source is the same) and listen to the best available. The Pulse Guard R MR Sapphire can compete with the best. The strengths of the 103R motor is it's balance, faithfulness to the music and great dimensionality. I own and use a Benz Micro LPS as our reference cartridge and it is better than the Guard R SMR but not to the degree you may think. If rating these two cartridges the SMR would get an 8 out of 10 and the LPS a 10 out of 10. Just for reference a Benz Micro Gullwing SLR ($3.6k) rates a 8/8.5 out of 10. The LPS has better detail and is fuller with better dimensional boundaries, all the things that make reproduced music so special. But look at the price difference $1100 vs $6k and without a system that can show all of these differences the extra money is a waste. The Pulse Guard R SMR is the best bargain in all of the MC cartridges available.

To the 103R's credit it continues to evolve and improve it's performance with each new modification. I do not think the 103R is done even now (Pulse Guard body, 40 micro dampers, Sapphire cantilever and MR diamond) it keeps getting better and I have not even begun experimenting with the magnet yet, stay tuned for more.

Click in this section and go to Vinyl Engine for information on Denon cartridges and the many 103 versions.