Thank you, dear friends. Together we have groped around in the dark and finally found the light switch due to collective efforts. I even have some information now about differences between SX and N, but maybe not the whole story. |
Thank, Geoch. This is not so for the 308N? I had the impression that the SX designation might have something to do with the material of which the arm wand is made, but I am far from certain, which is why I asked. Anyway, your info would suggest why there is such a large price differential between the two. |
Thanks, Raul. There are several 308SXs for sale, on eBay and elsewhere. In most cases they do have an original SAEC headshell, but it is not the ceramic one. Don't know whether or not that means the headshell is not original to the tonearm. (I think I did see one for sale in Hong kong that does have the ceramic headshell.)
My major reason for being interested in the SAEC has to do with the fact that with my L07D turntable I received an accessory OEM Kenwood arm board that bolts to the rear of the chassis to allow one to mount a second tonearm. This is really nicely made, heavy, and seems to have been cut for the SAEC 308 specifically. Looks like it will accept either the 308N or the 308SX. But it will not accept the 407 or 506, based on my examination of photos. (Kenwood made at least four different arm boards for the rear of the L07D chassis; each one is dedicated to a different vintage tonearm. Wonder whether they made one for Lustre.) I readily concede the the Lustre may be superior, because I certainly have no basis to argue. On the other hand, I am not inclined right now to spend about $1100 to buy the 308SX. That decision will have to wait a bit while I sell other stuff. |
Dear Geoch, You bring up an interesting topic. I have read elsewhere that the ideal geometry for the SAEC is "unusual", but no one says what it is. Is it Stevenson type? I learned from trying to use Baerwald with my Dynavector DV505 (which IS designed for Stevenson) that strange and unpleasant distortions arise if you have to twist the cartridge in the headshell in order to conform to some iconic geometry. (I think the cause is magnified with the DV, because of its very short vertically pivoted arm.) When I finally found a Stevenson protractor and subsequently realigned my cartridge, those distortions disappeared. Ergo, I would want to know exactly how to align the SAEC 308SX so as to be able also to align the cartridge body in its headshell. And yes, it makes no sense to mess around with a headshell that does not have slots to permit fore and aft adjustment of the cartridge body, but I would rather not twist the cartridge body.
What is ULS3X? Is that the designation for the SAEC ceramic headshell? If so, am I correct in thinking that you are in disagreement with Raul on using the ceramic with the 308SX? |
Dear Geoch, Good point! I do have the armboard made by Kenwood specifically to fit the SAEC 308 to its L07D. It is reasonable to assume that the Kenwood engineers at least knew what SAEC intended in terms of geometry, so I should not have a problem, even without knowing the correct geometry per se. (I do recall that the preferred null points are given on the Vinyl Engine website, so one could work backward from that as well.) The Kenwood installation does allow for some "wiggle room"; one can slide the armboard from side to side a few mm each way to bring things into alignment, before tightening it down.
To answer your question about pivot to spindle distance, I cannot very well determine that unless or until I purchase a 308 and install it. One could estimate it by assuming that the SAEC pivot would lie right over the exact center of the hole in the arm board, I suppose. |
Yes, I know about the VE data, and I did see your earlier post, now that you've reminded me. In fact, I just mentioned that VE gives the two null points. I have been meaning to compare their numbers to Stevenson and Baerwald, just for interest. Thanks for your many other insights into the possible differences between SX and N versions of 308. My choice would be to use an alignment that leaves the cartridge aligned with the midline of the headshell. If Baerwald won't do that, and I suspect it won't, I would not use Baerwald. I would choose the data given on VE, if those are the SAEC data, indeed. |
Dear Nandric, thanks for your insights. Please do note however the title of this thread, which is to say that I do know about the SX and N versions, but I want to know what differentiates one from the other, especially since the SX is now valued at about double that of the N version. By all accounts and from all information available on the internet (which isn't much), the SX version came after the N version, so I don't know why N would stand for "new", but it might have been new with respect to some preceding design.
The correct geometry should not be so much of a mystery. One could measure the offset angle of the headshell, and combining that information with the null points (given on VE), one can quickly say that the data do or do not conform to Baerwald or more likely Stevenson. (From all the other posts, it seems almost a sure thing that this tonearm was not designed for Baerwald.) I guess I will look at those numbers first. As I noted above, I have an armboard designed specifically for this tonearm, so I am probably going to be OK even if ignorant. |
Yes, Raul. You were correct earlier when you mentioned that the 407 (at 9 inches) is a bit shorter than the 308 (at about 9.5 inches). |
Tonight I had a chance to go poking around on Vinyl Engine for more info on these two tonearms,
(1) It appears that Nicola may be correct; the "N" may stand for "NEW". On VE, there is a reprint of the brochure for 308NEW.
(2) The 308SX is shown with the ceramic headshell; the 308N does not have the ceramic headshell. So that was one difference. The SX version has larger heavier "ears" flanking the bearing housing, to increase lateral effective mass. The arm tube of the SX might or might not be different from the N.
(3) The P2S distance for the N and probably for the SX is given as 235mm. Only 5mm of stylus overhang is recommended, for an effective length of 240mm. With a headshell offset angle of only 12 degrees, this results in an inner null point of 39.2mm (!) and an outer null point of 60.6mm. The ad copy says no tracing distortion on innermost grooves. I can believe that, since at 39.2mm from the spindle, the stylus is at best reaching the run-out grooves if not only the outer edge of the label. At 60.6mm it would probably be within the innermost cut of the LP. So they compromised the tracking angle over the whole rest of the LP in order to minimize tracking angle error in the innermost grooves. In contrast, Stevenson results in null points at ~60mm and ~117mm. And Baerwald and Lofgren B both have their null points farther away from the spindle than Stevenson. So the SAEC geometry is strange, indeed. Why choose to set your tonearm up so that only one null point occurs where there is music? Dunno. For one thing, the small headshell offset angle would tend to reduce skating force. |
Dear Nicola or anyone else, What do you think was meant by the statement you quoted: "it is not advised to optimize the geometry, or the resonance of the system will change to such an extent that the arm will not track properly."
What does that mean, exactly? What is the definition of "optimize" in that sentence? It would seem that they mean one should use the recommended and indeed strange SAEC parameters and that the warning not to "optimize" means not to use one of the more standard geometries, each of which gives two null points between outermost and innermost grooves. |
Dear Nicola, I do not think so badly of the SAEC 308, just because of the weird geometry. As I said, the very small angle of offset of the headshell (12 degrees) means that there will be less skating force than for any of the standard geometries (where offset angle is at least 20 degrees). This may mitigate any issues with tracking angle types of distortion. Also, I have the RS Labs RS A1 tonearm, which has NO null points across the surface of the LP, and sounds excellent. So I am not so concerned about tracking angle distortion per se. Anyway, based on what Raul wrote, the 308SX, 407/23, and 506 are "cousins". But now I am thinking that maybe the "23" refers to the angle of offset of the headshell. Twenty-three degrees would correspond to Baerwald or Lofgren. In that way, you are ok with your 407/23. Maybe this is also why the 407/23 is so costly now, compared to the 308s. In fact, it would be informative if you can take a protractor and estimate the angle of offset of the headshell on yours. |
