The other difference between the two SME 12" arms is that the 312S has a detachable headshell for easy cartridge swapping and azimuth adjustment while the V-12 has a fixed headshell for greater rigidity. I don't know if this difference is audible per se, but the possiblilty of adjusting azimuth is certainly a benefit. |
I have read that the spring is damped so it should not vibrate much anyway. But Jea48 raises an interesting question. I had assumed that the spring would be compressed, not streched out at the 0.0g setting. I wonder which is which. I have set my dial to 0.0 and will listen for a few days and than switch back and report if I notice any improvement. My PC-1 is on the heavier side, so the counterweight does move significantly in toward the arm's pivot point now that it is balanced statically. And that must be better for the arm's enertia, even if it isn't audible. |
I have just completed a careful comparison of dynamic VTF versus static VTF on my SME V with Air Tight PC-1 cartridge.
I can notice a very subtle difference in my system. I hear more micro details, better sense of air and room sounds with dynamic VTF. Bass notes are slightly fuller and more rich. This comes at the cost of slightly crisper, snappier transients, leading edge sounds on cymbals and piano as heard with static VTF.
I would not describe the sound as more relaxed. It is a bit more 3-D and involving for me with dynamic VTF. It is slightly drier, but more exciting with static VTF. Both sound good and the difference is extremely small to my ears in my system. Without doing an A-B-A intense listening test, I probably would never have noticed a difference. The ease of adjusting VTF with the dial is so much more convenient, that for some, this may be the deciding factor, but I don't adjust VTF once it is set. My records are all pretty flat, so perhaps I would notice a bigger differnce with warped LPs as Daniel suggests.
My findings correspond fairly closely to the descriptions from Raul and Daniel mentioned above, but I have strained to reach these conclusions. They certainly have more experience and perhaps their systems are more resolving, so these differences may be more important in their systems and to their individual preferences. I agree with both Raul and Daniel that it comes down to personal opinions as to which is better in a given system and to a certain set of ears. Interestingly, when I started this thread, I thought there would be a more definitive answer. |
Daniel and Raul,
Regarding your advice about damping: I have not used damping on my SME V since I got the Air Tight PC-1. In fact I removed the damping trough and cleaned out any silicone residue. I used the resonance calculator and my cartridge/tonearm combination seems pretty good at 10.5 Hz.
SME V eff. mass = 10-11g
PC-1 weight = 12g
PC-1 compliance = 10cu
Resonance = 10.5 Hz
Settings: no damping, 1.0g antiskate, 2.1g VTF, VTA level with 150g LP, loading at 22ohm with Pass Labs XOno phono amp. Cartridge aligned using MINT Tractor made for specific arm/cartridge combo. Azimuth, zenith and null points all correct.
The PC-1 is a fairly heavy cartridge with low/medium compliance. The math seems to work and it sounds wonderful. Is this because the arm is quite rigid with good internal damping? |
Raul and Daniel,
Thank you very much for your comments and thoughtful advice. Raul, I did try loading the PC-1 with 100 ohms just like my old Sumiko Celebration, but something was missing. With the help of a friend, I went up to roughly 120, 140, 200, 249 and 452 and down to 75, 47, 22, and 10. As you may know the XOno has about 230 possible settings and has an active initial gain stage. I agree that the 22ohm setting seems low, but for me there is a good balance between bass definition and weight and good upper end extension without stridence. But more importantly, at 22ohm everything suddenly sounded right with air and presence. At 22 ohms, the "gestahlt" hit me and everything just sounded right.
Regarding tiny VTA adjustments: The biggest problem with the SME V design is the difficulty of adjusting height. Every time I try it, the arm column moves slightly out of vertical because the VTA screw is off center and I have to recheck azimuth. This is a big problem with the SME arm. So I tend to make very tiny VTA adjustments by altering VTF. And unless I bought the TriPlanar or Phantom, I would not consider changing VTA for each different LP thickness like some people do. |
Hi Albert,
That is interesting. When I loosen the set-screws at the base of the arm, I can tilt the cylindrical arm post slightly to the left or right. I had thought this was a way to adjust azimuth before tightening the screws again. Then a read a post by dougdeacon that this was not a good idea because the bearing would then not be level if the arm post were not vertical or plumb. That got me thinking that if the arm post is not truely vertical, or plumb, then all the rest of the geometry as the arm swings toward the LP center is not correct either. So now I check for level with a bubble level placed on the flat surface to the arm lock which I assume is perpendicular to the arm post. When it is level, I then retighten the setscrews. Is this slight play in the arm post not normal?
The issue with the VTA screw is that it is off-center from the pivot point so as it is turned clockwise to raise the arm, it exerts a force which tilts the arm slightly to the right as viewed from the front. I then tilt it back by pushing the bottom of the post to the right, moving the top back to the left and making it true vertical again. I thought all SME arms had this slight play at the base.
I now agree with all of those people who say that azimuth is not adjustable on the SME arms because the post has to remain truely vertical or plumb. Fortunately, my PC-1 cantilever is "perfectly" straight and centered in the vertical plane.
This thread is getting off the topic of dynamic vs. static VTF and becoming more about adjusting the SME V arm. Perhaps a topic for another thread. Sorry. |
Alex,
Thank you for that suggestion. It makes sense. |
Axel,
I agree with you about removing the SME V damping trough. I removed it for cleaning as per the SME instructions and then reinstalled it for aesthetic reasons. I can't imagine there being any sonic difference one way or the other. I don't think that "some purists" are using their arms with the trough removed, or at least I have'nt read of any. I think they just don't fill it with silicone. My silicon had become somewhat hard and I simply wanted to clean it out.
It seems to me that SME designed the damping trough for some sonic reason. They do not mention that it should be used when there is a cartridge/arm mismatch but this is territory that I know nothing about. Daniel's point about it being used to dampen resonances created by a cartridge/arm mismatch does make sense. I have not done a careful listening test. I wonder if this is about relative catilever movement between low versus high compliance cartridges and the stability of the arm moving across the LP. |
Well, it's been about a year and a half since I started this thread and I think I shall add a recent observation:
I have been researching new arms and am intrigued by the two SME 12" arms, the 312S and the V-12. Besides the detachable headshell on the 312S, the main difference seems to be static versus dynamic VTF. So I was checking the alignment of my SME V and thought I would retest my earlier observations about VTF. My system has changed in the past year, and with the addition of new monitor speakers, it is considerably more revealing than it was. I did an A-B-A test or dynamic-static-dynamic. I listened to Beethoven's Violin Concerto and some female vocals. In static mode at 2.1g VTF, the sound was flat, lacked subtle detail and was generally not involving, and these were LPs that I love and listen to often. Massed strings lacked the sense of individual musicians playing as a group. There was little or no hall information. It sounded 2-D. When I switched back to dynamic mode I noticed the change immediately. The sound was more full, had more weight, better air and sense of space, music filled the room rather than just the plane of the speakers. Massed strings sounded like many individual musicians playing together. Sounds reverberated in the hall. Voices were fleshy, not dry. In short, the experience was much more real and involving. I quickly forgot about listening for details and just got lost in the music.
The difference was not nearly as subtle as I found it to be a year ago. I immediately noticed the improvement. Perhaps it is because I have another year of listening experience, perhaps my system is just more revealing now. Whatever the reason, I now much prefer dynamic VTF with the SME V arm in my system.
Now, on to trying to compare my SME V to the V-12 and a few other arms. |
