635JM-R versus JM64 necks (Silver Sky)

[Wolfhound]

Hello All - I’m looking for a 2020 Silver Sky and know that the rosewood fretboard versions came with a slightly different neck carve (635JM-R). The thing is I have seen a few 2020 rosewood models with a JM64 neck. I’ve heard that these two neck shapes are very, very close but just don’t understand why they’re coming with different neck codes than listed on the website. Does anybody have insight as to how these necks compare? It’s so hard to know without getting your hands on them! Thanks so much.

 

[greenlemon]

So I had a chance to test both JM64 and 635JM-R. From what I know, JM64 is the original neck that the SS launched with whereas the 635JM-R is the 'modified' neck for late 2020 & 2021 SS (rosewood only).

-JM64: I found the older neck to be more comfortable. It wraps around your hand, you will enjoy it if you like having your thumb over the Low E string. It may feel bit thick due to the shoulders. I never tried the Fender SRV neck, but I assume it may feel similar to the JM64. The frets are more vintage spec.
-635JM-R: This is the neck with "rounded shoulders" where the shoulders has been removed a bit. Based on other people, it is apparently thicker on the measurement. To me, it feels smaller due to the rounded shoulders. It has larger frets compared to the JM64. Based on the PRS website, the maple version still has the original neck carve (JM64)
-My thought: I personally prefer JM64 over 635JM-R. I found the 635JM-R neck to be more close to modern C with bit of thickness, the shoulders was something that made the SS neck special imo.

Hope this helps!

 

[Wolfhound]

So I had a chance to test both JM64 and 635JM-R. From what I know, JM64 is the original neck that the SS launched with whereas the 635JM-R is the 'modified' neck for late 2020 & 2021 SS (rosewood only).

-JM64: I found the older neck to be more comfortable. It wraps around your hand, you will enjoy it if you like having your thumb over the Low E string. It may feel bit thick due to the shoulders. I never tried the Fender SRV neck, but I assume it may feel similar to the JM64. The frets are more vintage spec.
-635JM-R: This is the neck with "rounded shoulders" where the shoulders has been removed a bit. Based on other people, it is apparently thicker on the measurement. To me, it feels smaller due to the rounded shoulders. It has larger frets compared to the JM64. Based on the PRS website, the maple version still has the original neck carve (JM64)
-My thought: I personally prefer JM64 over 635JM-R. I found the 635JM-R neck to be more close to modern C with bit of thickness, the shoulders was something that made the SS neck special imo.

Hope this helps!

The response I got from PRS was that these two carves were so similar that the tolerances overlapped! Anyway - I’ve been liking the neck on my 2021 SS since late January! And I also really like the 7.25 radius.

 

[greenlemon]

The response I got from PRS was that these two carves were so similar that the tolerances overlapped! Anyway - I’ve been liking the neck on my 2021 SS since late January! And I also really like the 7.25 radius.

I hope you enjoy your SS, they are great guitars!

 

[bodia]

Shawn originally responded that the carves were so close some at PRS didn't even want to announce there was a difference to avoid confusion. That said, the newer neck was to have a little difference on the thumb side shoulder, IIRC.